1
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Mooers G, Pritchard M, Beucler T, Srivastava P, Mangipudi H, Peng L, Gentine P, Mandt S. Author Correction: Comparing storm resolving models and climates via unsupervised machine learning. Sci Rep 2024; 14:7391. [PMID: 38548802 PMCID: PMC10978913 DOI: 10.1038/s41598-024-57767-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/01/2024] Open
Affiliation(s)
- Griffin Mooers
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92697, USA.
| | - Mike Pritchard
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92697, USA
- NVIDIA, Santa Clara, CA, 95050, USA
| | - Tom Beucler
- Institute of Earth Surface Dynamics, University of Lausanne, 1015, Lausanne, Switzerland
| | - Prakhar Srivastava
- Department of Computer Science, University of California at Irvine, Irvine, CA, 92617, USA
| | - Harshini Mangipudi
- Department of Computer Science, University of California at Irvine, Irvine, CA, 92617, USA
| | - Liran Peng
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92697, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Stephan Mandt
- Department of Computer Science, University of California at Irvine, Irvine, CA, 92617, USA
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2
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Beucler T, Gentine P, Yuval J, Gupta A, Peng L, Lin J, Yu S, Rasp S, Ahmed F, O’Gorman PA, Neelin JD, Lutsko NJ, Pritchard M. Climate-invariant machine learning. Sci Adv 2024; 10:eadj7250. [PMID: 38324696 PMCID: PMC10849594 DOI: 10.1126/sciadv.adj7250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 01/05/2024] [Indexed: 02/09/2024]
Abstract
Projecting climate change is a generalization problem: We extrapolate the recent past using physical models across past, present, and future climates. Current climate models require representations of processes that occur at scales smaller than model grid size, which have been the main source of model projection uncertainty. Recent machine learning (ML) algorithms hold promise to improve such process representations but tend to extrapolate poorly to climate regimes that they were not trained on. To get the best of the physical and statistical worlds, we propose a framework, termed "climate-invariant" ML, incorporating knowledge of climate processes into ML algorithms, and show that it can maintain high offline accuracy across a wide range of climate conditions and configurations in three distinct atmospheric models. Our results suggest that explicitly incorporating physical knowledge into data-driven models of Earth system processes can improve their consistency, data efficiency, and generalizability across climate regimes.
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Affiliation(s)
- Tom Beucler
- Faculty of Geosciences and Environment, University of Lausanne, Lausanne, VD 1015, Switzerland
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
| | - Janni Yuval
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ankitesh Gupta
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
| | - Liran Peng
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
| | - Jerry Lin
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
| | - Sungduk Yu
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
| | | | - Fiaz Ahmed
- Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Paul A. O’Gorman
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - J. David Neelin
- Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Nicholas J. Lutsko
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92037, USA
| | - Michael Pritchard
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
- NVIDIA, Santa Clara, CA 95050, USA
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3
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Lian X, Peñuelas J, Ryu Y, Piao S, Keenan TF, Fang J, Yu K, Chen A, Zhang Y, Gentine P. Diminishing carryover benefits of earlier spring vegetation growth. Nat Ecol Evol 2024; 8:218-228. [PMID: 38172284 DOI: 10.1038/s41559-023-02272-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 11/13/2023] [Indexed: 01/05/2024]
Abstract
Spring vegetation growth can benefit summer growth by increasing foliage area and carbon sequestration potential, or impair it by consuming additional resources needed for sustaining subsequent growth. However, the prevalent driving mechanism and its temporal changes remain unknown. Using satellite observations and long-term atmospheric CO2 records, here we show a weakening trend of the linkage between spring and summer vegetation growth/productivity in the Northern Hemisphere during 1982-2021. This weakening is driven by warmer and more extreme hot weather that becomes unfavourable for peak-season growth, shifting peak plant functioning away from earlier periods. This is further exacerbated by seasonally growing ecosystem water stress due to reduced water supply and enhanced water demand. Our finding suggests that beneficial carryover effects of spring growth on summer growth are diminishing or even reversing, acting as an early warning sign of the ongoing shift of climatic effects from stimulating to suppressing plant photosynthesis during the early to peak seasons.
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Affiliation(s)
- Xu Lian
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA.
| | - Josep Peñuelas
- CREAF, Barcelona, Spain
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Barcelona, Spain
| | - Youngryel Ryu
- Department of Landscape Architecture and Rural Systems Engineering, Seoul National University, Seoul, South Korea
| | - Shilong Piao
- Institute of Carbon Neutrality, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
| | - Trevor F Keenan
- Earth and Environmental Sciences Area, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Environmental Science Policy and Management, UC Berkeley, Berkeley, CA, USA
| | - Jianing Fang
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | - Kailiang Yu
- Department of Ecology & Evolutionary Biology, High Meadows Environmental Institute, Princeton University, Princeton, NJ, USA
| | - Anping Chen
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
| | - Yao Zhang
- Institute of Carbon Neutrality, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- Center for Learning the Earth with Artificial intelligence and Physics (LEAP), Columbia University, New York, NY, USA
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4
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Wu Y, Yin X, Zhou G, Bruijnzeel LA, Dai A, Wang F, Gentine P, Zhang G, Song Y, Zhou D. Rising rainfall intensity induces spatially divergent hydrological changes within a large river basin. Nat Commun 2024; 15:823. [PMID: 38280877 PMCID: PMC10821892 DOI: 10.1038/s41467-023-44562-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 12/19/2023] [Indexed: 01/29/2024] Open
Abstract
Droughts or floods are usually attributed to precipitation deficits or surpluses, both of which may become more frequent and severe under continued global warming. Concurring large-scale droughts in the Southwest and flooding in the Southeast of China in recent decades have attracted considerable attention, but their causes and interrelations are not well understood. Here, we examine spatiotemporal changes in hydrometeorological variables and investigate the mechanism underlying contrasting soil dryness/wetness patterns over a 54-year period (1965-2018) across a representative mega-watershed in South China-the West River Basin. We demonstrate that increasing rainfall intensity leads to severe drying upstream with decreases in soil water storage, water yield, and baseflow, versus increases therein downstream. Our study highlights a simultaneous occurrence of increased drought and flooding risks due to contrasting interactions between rainfall intensification and topography across the river basin, implying increasingly vulnerable water and food security under continued climate change.
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Affiliation(s)
- Yiping Wu
- Institute of Global Environmental Change, Department of Earth & Environmental Science, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, PR China
- National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Xi'an, 710061, PR China
| | - Xiaowei Yin
- Institute of Global Environmental Change, Department of Earth & Environmental Science, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, PR China
| | - Guoyi Zhou
- Institute of Ecology, School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, PR China.
| | - L Adrian Bruijnzeel
- Department of Geography, King's College London, London, WC2B 4BG, UK
- Institute of International Rivers and Eco-Security, Yunnan University, Kunming, 650091, PR China
| | - Aiguo Dai
- Department of Atmospheric and Environmental Sciences, University at Albany, State University of New York, Albany, NY, 12222, USA
| | - Fan Wang
- Institute of Global Environmental Change, Department of Earth & Environmental Science, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, PR China
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Earth Institute, Columbia University, New York, NY, 10027, USA
| | - Guangchuang Zhang
- Institute of Global Environmental Change, Department of Earth & Environmental Science, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, PR China
| | - Yanni Song
- Technology Innovation Center for Land Engineering and Human Settlements, Shaanxi Land Engineering Construction Group Co. Ltd and Xi'an Jiaotong University, Xi'an, 710115, PR China
| | - Decheng Zhou
- Institute of Ecology, School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, PR China
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5
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Mooers G, Pritchard M, Beucler T, Srivastava P, Mangipudi H, Peng L, Gentine P, Mandt S. Comparing storm resolving models and climates via unsupervised machine learning. Sci Rep 2023; 13:22365. [PMID: 38102176 PMCID: PMC10724240 DOI: 10.1038/s41598-023-49455-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 12/08/2023] [Indexed: 12/17/2023] Open
Abstract
Global storm-resolving models (GSRMs) have gained widespread interest because of the unprecedented detail with which they resolve the global climate. However, it remains difficult to quantify objective differences in how GSRMs resolve complex atmospheric formations. This lack of comprehensive tools for comparing model similarities is a problem in many disparate fields that involve simulation tools for complex data. To address this challenge we develop methods to estimate distributional distances based on both nonlinear dimensionality reduction and vector quantization. Our approach automatically learns physically meaningful notions of similarity from low-dimensional latent data representations that the different models produce. This enables an intercomparison of nine GSRMs based on their high-dimensional simulation data (2D vertical velocity snapshots) and reveals that only six are similar in their representation of atmospheric dynamics. Furthermore, we uncover signatures of the convective response to global warming in a fully unsupervised way. Our study provides a path toward evaluating future high-resolution simulation data more objectively.
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Affiliation(s)
- Griffin Mooers
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92697, USA.
| | - Mike Pritchard
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92697, USA
| | - Tom Beucler
- Institute of Earth Surface Dynamics, University of Lausanne, 1015, Lausanne, Switzerland
| | - Prakhar Srivastava
- Department of Computer Science, University of California at Irvine, Irvine, CA, 92617, USA
| | - Harshini Mangipudi
- Department of Computer Science, University of California at Irvine, Irvine, CA, 92617, USA
| | - Liran Peng
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92697, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Stephan Mandt
- Department of Computer Science, University of California at Irvine, Irvine, CA, 92617, USA
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6
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Giardina F, Gentine P, Konings AG, Seneviratne SI, Stocker BD. Diagnosing evapotranspiration responses to water deficit across biomes using deep learning. New Phytol 2023; 240:968-983. [PMID: 37621238 DOI: 10.1111/nph.19197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 07/23/2023] [Indexed: 08/26/2023]
Abstract
Accounting for water limitation is key to determining vegetation sensitivity to drought. Quantifying water limitation effects on evapotranspiration (ET) is challenged by the heterogeneity of vegetation types, climate zones and vertically along the rooting zone. Here, we train deep neural networks using flux measurements to study ET responses to progressing drought conditions. We determine a water stress factor (fET) that isolates ET reductions from effects of atmospheric aridity and other covarying drivers. We regress fET against the cumulative water deficit, which reveals the control of whole-column moisture availability. We find a variety of ET responses to water stress. Responses range from rapid declines of fET to 10% of its water-unlimited rate at several savannah and grassland sites, to mild fET reductions in most forests, despite substantial water deficits. Most sensitive responses are found at the most arid and warm sites. A combination of regulation of stomatal and hydraulic conductance and access to belowground water reservoirs, whether in groundwater or deep soil moisture, could explain the different behaviors observed across sites. This variety of responses is not captured by a standard land surface model, likely reflecting simplifications in its representation of belowground water storage.
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Affiliation(s)
- Francesco Giardina
- Institute of Agricultural Sciences, Department of Environmental Systems Science, ETH Zürich, Zürich, CH-8092, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
- Center for Learning the Earth with Artificial Intelligence and Physics (LEAP), Columbia University, New York, NY, 10027, USA
| | - Alexandra G Konings
- Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA
| | - Sonia I Seneviratne
- Institute for Atmospheric and Climate Science, Department of Environmental Systems Science, ETH Zurich, Zürich, CH-8092, Switzerland
| | - Benjamin D Stocker
- Institute of Agricultural Sciences, Department of Environmental Systems Science, ETH Zürich, Zürich, CH-8092, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
- Institute of Geography, University of Bern, Hallerstrasse 12, Bern, 3012, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Falkenplatz 16, Bern, 3012, Switzerland
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7
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Lamb KD, Gentine P. Zero-shot learning of aerosol optical properties with graph neural networks. Sci Rep 2023; 13:18777. [PMID: 37907512 PMCID: PMC10618469 DOI: 10.1038/s41598-023-45235-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/17/2023] [Indexed: 11/02/2023] Open
Abstract
Black carbon (BC), a strongly absorbing aerosol sourced from combustion, is an important short-lived climate forcer. BC's complex morphology contributes to uncertainty in its direct climate radiative effects, as current methods to accurately calculate the optical properties of these aerosols are too computationally expensive to be used online in models or for observational retrievals. Here we demonstrate that a Graph Neural Network (GNN) trained to predict the optical properties of numerically-generated BC fractal aggregates can accurately generalize to arbitrarily shaped particles, including much larger ([Formula: see text]) aggregates than in the training dataset. This zero-shot learning approach could be used to estimate single particle optical properties of realistically-shaped aerosol and cloud particles for inclusion in radiative transfer codes for atmospheric models and remote sensing inversions. In addition, GNN's can be used to gain physical intuition on the relationship between small-scale interactions (here of the spheres' positions and interactions) and large-scale properties (here of the radiative properties of aerosols).
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Affiliation(s)
- K D Lamb
- Department of Earth and Environmental Engineering, Columbia University, New York, USA.
| | - P Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, USA
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8
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Li W, Pacheco-Labrador J, Migliavacca M, Miralles D, Hoek van Dijke A, Reichstein M, Forkel M, Zhang W, Frankenberg C, Panwar A, Zhang Q, Weber U, Gentine P, Orth R. Widespread and complex drought effects on vegetation physiology inferred from space. Nat Commun 2023; 14:4640. [PMID: 37582763 PMCID: PMC10427636 DOI: 10.1038/s41467-023-40226-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Accepted: 07/12/2023] [Indexed: 08/17/2023] Open
Abstract
The response of vegetation physiology to drought at large spatial scales is poorly understood due to a lack of direct observations. Here, we study vegetation drought responses related to photosynthesis, evaporation, and vegetation water content using remotely sensed data, and we isolate physiological responses using a machine learning technique. We find that vegetation functional decreases are largely driven by the downregulation of vegetation physiology such as stomatal conductance and light use efficiency, with the strongest downregulation in water-limited regions. Vegetation physiological decreases in wet regions also result in a discrepancy between functional and structural changes under severe drought. We find similar patterns of physiological drought response using simulations from a soil-plant-atmosphere continuum model coupled with a radiative transfer model. Observation-derived vegetation physiological responses to drought across space are mainly controlled by aridity and additionally modulated by abnormal hydro-meteorological conditions and vegetation types. Hence, isolating and quantifying vegetation physiological responses to drought enables a better understanding of ecosystem biogeochemical and biophysical feedback in modulating climate change.
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Affiliation(s)
- Wantong Li
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany.
| | - Javier Pacheco-Labrador
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | | | - Diego Miralles
- Hydro-Climate Extremes Lab (H-CEL), Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Anne Hoek van Dijke
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Markus Reichstein
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
- Integrative Center for Biodiversity Research (iDIV), Leipzig, Germany
| | - Matthias Forkel
- Institute of Photogrammetry and Remote Sensing, Technische Universität Dresden, Dresden, Germany
| | - Weijie Zhang
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Christian Frankenberg
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, 91125, USA
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
| | - Annu Panwar
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Qian Zhang
- School of Geomatics Science and Technology, Nanjing Tech University, Nanjing, China
| | - Ulrich Weber
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Rene Orth
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
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9
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Li X, Ryu Y, Xiao J, Dechant B, Liu J, Li B, Jeong S, Gentine P. New-generation geostationary satellite reveals widespread midday depression in dryland photosynthesis during 2020 western U.S. heatwave. Sci Adv 2023; 9:eadi0775. [PMID: 37531429 PMCID: PMC10396307 DOI: 10.1126/sciadv.adi0775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 06/29/2023] [Indexed: 08/04/2023]
Abstract
Emerging new-generation geostationary satellites have broadened the scope for studying the diurnal cycle of ecosystem functions. We exploit observations from the Geostationary Operational Environmental Satellite-R series to examine the effect of a severe U.S. heatwave in 2020 on the diurnal variations of ecosystem photosynthesis. We find divergent responses of photosynthesis to the heatwave across vegetation types and aridity gradients, with drylands exhibiting widespread midday and afternoon depression in photosynthesis. The diurnal centroid and peak time of dryland gross primary production (GPP) substantially shift toward earlier morning times, reflecting notable water and heat stress. Our geostationary satellite-based method outperforms traditional radiation-based upscaling methods from polar-orbiting satellite snapshots in estimating daily GPP and GPP loss during heatwaves. These findings underscore the potential of geostationary satellites for diurnal photosynthesis monitoring and highlight the necessity to consider the increased diurnal asymmetry in GPP under stress when evaluating carbon-climate interactions.
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Affiliation(s)
- Xing Li
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Youngryel Ryu
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
- Department of Landscape Architecture and Rural Systems Engineering, College of Agriculture and Life Sciences, Seoul National University, South Korea
| | - Jingfeng Xiao
- Earth Systems Research Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH, USA
| | - Benjamin Dechant
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
- Leipzig University, Leipzig, Germany
| | - Jiangong Liu
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Bolun Li
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Sungchan Jeong
- Department of Landscape Architecture and Rural Systems Engineering, College of Agriculture and Life Sciences, Seoul National University, South Korea
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
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10
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Nathaniel J, Liu J, Gentine P. MetaFlux: Meta-learning global carbon fluxes from sparse spatiotemporal observations. Sci Data 2023; 10:440. [PMID: 37433802 DOI: 10.1038/s41597-023-02349-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 06/29/2023] [Indexed: 07/13/2023] Open
Abstract
We provide a global, long-term carbon flux dataset of gross primary production and ecosystem respiration generated using meta-learning, called MetaFlux. The idea behind meta-learning stems from the need to learn efficiently given sparse data by learning how to learn broad features across tasks to better infer other poorly sampled ones. Using meta-trained ensemble of deep models, we generate global carbon products on daily and monthly timescales at a 0.25-degree spatial resolution from 2001 to 2021, through a combination of reanalysis and remote-sensing products. Site-level validation finds that MetaFlux ensembles have lower validation error by 5-7% compared to their non-meta-trained counterparts. In addition, they are more robust to extreme observations, with 4-24% lower errors. We also checked for seasonality, interannual variability, and correlation to solar-induced fluorescence of the upscaled product and found that MetaFlux outperformed other machine-learning based carbon product, especially in the tropics and semi-arids by 10-40%. Overall, MetaFlux can be used to study a wide range of biogeochemical processes.
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Affiliation(s)
- Juan Nathaniel
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA.
| | - Jiangong Liu
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
- Climate School, Columbia University, New York, NY, 10027, USA
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11
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Feldman AF, Zhang Z, Yoshida Y, Gentine P, Chatterjee A, Entekhabi D, Joiner J, Poulter B. A multi-satellite framework to rapidly evaluate extreme biosphere cascades: The Western US 2021 drought and heatwave. Glob Chang Biol 2023; 29:3634-3651. [PMID: 37070967 DOI: 10.1111/gcb.16725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 04/04/2023] [Indexed: 06/06/2023]
Abstract
The increasing frequency and intensity of climate extremes and complex ecosystem responses motivate the need for integrated observational studies at low latency to determine biosphere responses and carbon-climate feedbacks. Here, we develop a satellite-based rapid attribution workflow and demonstrate its use at a 1-2-month latency to attribute drivers of the carbon cycle feedbacks during the 2020-2021 Western US drought and heatwave. In the first half of 2021, concurrent negative photosynthesis anomalies and large positive column CO2 anomalies were detected with satellites. Using a simple atmospheric mass balance approach, we estimate a surface carbon efflux anomaly of 132 TgC in June 2021, a magnitude corroborated independently with a dynamic global vegetation model. Integrated satellite observations of hydrologic processes, representing the soil-plant-atmosphere continuum (SPAC), show that these surface carbon flux anomalies are largely due to substantial reductions in photosynthesis because of a spatially widespread moisture-deficit propagation through the SPAC between 2020 and 2021. A causal model indicates deep soil moisture stores partially drove photosynthesis, maintaining its values in 2020 and driving its declines throughout 2021. The causal model also suggests legacy effects may have amplified photosynthesis deficits in 2021 beyond the direct effects of environmental forcing. The integrated, observation framework presented here provides a valuable first assessment of a biosphere extreme response and an independent testbed for improving drought propagation and mechanisms in models. The rapid identification of extreme carbon anomalies and hotspots can also aid mitigation and adaptation decisions.
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Affiliation(s)
- Andrew F Feldman
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
- NASA Postdoctoral Program, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - Zhen Zhang
- Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland, USA
| | - Yasuko Yoshida
- Science Systems and Applications, Inc. (SSAI), Lanham, Maryland, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, New York, USA
| | - Abhishek Chatterjee
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Dara Entekhabi
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Joanna Joiner
- Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - Benjamin Poulter
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
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12
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Bhouri MA, Gentine P. Memory-based parameterization with differentiable solver: Application to Lorenz '96. Chaos 2023; 33:073116. [PMID: 37408156 DOI: 10.1063/5.0131929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 06/06/2023] [Indexed: 07/07/2023]
Abstract
Physical parameterizations (or closures) are used as representations of unresolved subgrid processes within weather and global climate models or coarse-scale turbulent models, whose resolutions are too coarse to resolve small-scale processes. These parameterizations are typically grounded on physically based, yet empirical, representations of the underlying small-scale processes. Machine learning-based parameterizations have recently been proposed as an alternative solution and have shown great promise to reduce uncertainties associated with the parameterization of small-scale processes. Yet, those approaches still show some important mismatches that are often attributed to the stochasticity of the considered process. This stochasticity can be due to coarse temporal resolution, unresolved variables, or simply to the inherent chaotic nature of the process. To address these issues, we propose a new type of parameterization (closure), which is built using memory-based neural networks, to account for the non-instantaneous response of the closure and to enhance its stability and prediction accuracy. We apply the proposed memory-based parameterization, with differentiable solver, to the Lorenz '96 model in the presence of a coarse temporal resolution and show its capacity to predict skillful forecasts over a long time horizon of the resolved variables compared to instantaneous parameterizations. This approach paves the way for the use of memory-based parameterizations for closure problems.
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Affiliation(s)
- Mohamed Aziz Bhouri
- Department of Earth and Environmental Engineering, Columbia University, New York, New York 10027, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, New York 10027, USA
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13
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Gu L, Yin J, Gentine P, Wang HM, Slater LJ, Sullivan SC, Chen J, Zscheischler J, Guo S. Large anomalies in future extreme precipitation sensitivity driven by atmospheric dynamics. Nat Commun 2023; 14:3197. [PMID: 37268612 PMCID: PMC10238374 DOI: 10.1038/s41467-023-39039-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 05/26/2023] [Indexed: 06/04/2023] Open
Abstract
Increasing atmospheric moisture content is expected to intensify precipitation extremes under climate warming. However, extreme precipitation sensitivity (EPS) to temperature is complicated by the presence of reduced or hook-shaped scaling, and the underlying physical mechanisms remain unclear. Here, by using atmospheric reanalysis and climate model projections, we propose a physical decomposition of EPS into thermodynamic and dynamic components (i.e., the effects of atmospheric moisture and vertical ascent velocity) at a global scale in both historical and future climates. Unlike previous expectations, we find that thermodynamics do not always contribute to precipitation intensification, with the lapse rate effect and the pressure component partly offsetting positive EPS. Large anomalies in future EPS projections (with lower and upper quartiles of -1.9%/°C and 8.0%/°C) are caused by changes in updraft strength (i.e., the dynamic component), with a contrast of positive anomalies over oceans and negative anomalies over land areas. These findings reveal counteracting effects of atmospheric thermodynamics and dynamics on EPS, and underscore the importance of understanding precipitation extremes by decomposing thermodynamic effects into more detailed terms.
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Affiliation(s)
- Lei Gu
- State Key Laboratory of Water Resources Engineering and Management, Wuhan University, Wuhan, Hubei, 430072, P.R. China
- Hubei Key Laboratory of Digital River Basin Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Jiabo Yin
- State Key Laboratory of Water Resources Engineering and Management, Wuhan University, Wuhan, Hubei, 430072, P.R. China.
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- Climate School, Columbia University, New York, NY, USA
| | - Hui-Min Wang
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore
| | - Louise J Slater
- School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Sylvia C Sullivan
- Department of Chemical & Environmental Engineering, University of Arizona, Tucson, AZ, USA
| | - Jie Chen
- State Key Laboratory of Water Resources Engineering and Management, Wuhan University, Wuhan, Hubei, 430072, P.R. China
| | - Jakob Zscheischler
- Department of Computational Hydrosystems, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Shenglian Guo
- State Key Laboratory of Water Resources Engineering and Management, Wuhan University, Wuhan, Hubei, 430072, P.R. China
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14
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Zhang Y, Fang J, Smith WK, Wang X, Gentine P, Scott RL, Migliavacca M, Jeong S, Litvak M, Zhou S. Satellite solar-induced chlorophyll fluorescence tracks physiological drought stress development during 2020 southwest US drought. Glob Chang Biol 2023; 29:3395-3408. [PMID: 36929655 DOI: 10.1111/gcb.16683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 03/13/2023] [Indexed: 05/16/2023]
Abstract
Monitoring and estimating drought impact on plant physiological processes over large regions remains a major challenge for remote sensing and land surface modeling, with important implications for understanding plant mortality mechanisms and predicting the climate change impact on terrestrial carbon and water cycles. The Orbiting Carbon Observatory 3 (OCO-3), with its unique diurnal observing capability, offers a new opportunity to track drought stress on plant physiology. Using radiative transfer and machine learning modeling, we derive a metric of afternoon photosynthetic depression from OCO-3 solar-induced chlorophyll fluorescence (SIF) as an indicator of plant physiological drought stress. This unique diurnal signal enables a spatially explicit mapping of plants' physiological response to drought. Using OCO-3 observations, we detect a widespread increasing drought stress during the 2020 southwest US drought. Although the physiological drought stress is largely related to the vapor pressure deficit (VPD), our results suggest that plants' sensitivity to VPD increases as the drought intensifies and VPD sensitivity develops differently for shrublands and grasslands. Our findings highlight the potential of using diurnal satellite SIF observations to advance the mechanistic understanding of drought impact on terrestrial ecosystems and to improve land surface modeling.
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Affiliation(s)
- Yao Zhang
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
- Institute of Carbon Neutrality, Peking University, Beijing, China
| | - Jianing Fang
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
- Department of Earth and Environmental Engineering, Columbia University, New York, New York, USA
| | - William Kolby Smith
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, USA
| | - Xian Wang
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, New York, USA
| | - Russell L Scott
- Southwest Watershed Research Center, USDA Agricultural Research Service, Tucson, Arizona, USA
| | | | - Sujong Jeong
- Department of Environmental Planning, Graduate School of Environmental Studies, Seoul National University, Seoul, South Korea
| | - Marcy Litvak
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Sha Zhou
- State Key Laboratory of Earth Surface Processes and Resources Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, China
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15
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Zhang Z, Cescatti A, Wang YP, Gentine P, Xiao J, Guanter L, Huete AR, Wu J, Chen JM, Ju W, Peñuelas J, Zhang Y. Large diurnal compensatory effects mitigate the response of Amazonian forests to atmospheric warming and drying. Sci Adv 2023; 9:eabq4974. [PMID: 37235657 DOI: 10.1126/sciadv.abq4974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 04/25/2023] [Indexed: 05/28/2023]
Abstract
Photosynthesis and evapotranspiration in Amazonian forests are major contributors to the global carbon and water cycles. However, their diurnal patterns and responses to atmospheric warming and drying at regional scale remain unclear, hindering the understanding of global carbon and water cycles. Here, we used proxies of photosynthesis and evapotranspiration from the International Space Station to reveal a strong depression of dry season afternoon photosynthesis (by 6.7 ± 2.4%) and evapotranspiration (by 6.1 ± 3.1%). Photosynthesis positively responds to vapor pressure deficit (VPD) in the morning, but negatively in the afternoon. Furthermore, we projected that the regionally depressed afternoon photosynthesis will be compensated by their increases in the morning in future dry seasons. These results shed new light on the complex interplay of climate with carbon and water fluxes in Amazonian forests and provide evidence on the emerging environmental constraints of primary productivity that may improve the robustness of future projections.
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Affiliation(s)
- Zhaoying Zhang
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, International Institute for Earth System Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
- Yuxiu Postdoctoral Institute, Nanjing University, Nanjing, Jiangsu 210023, China
- Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural Resources, School of Geography and Ocean Science, Nanjing University, Nanjing, Jiangsu 210023, China
| | | | - Ying-Ping Wang
- CSIRO, Oceans and Atmosphere, Private Bag 1, Aspendale, Victoria 3195, Australia
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | - Jingfeng Xiao
- Earth Systems Research Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH, USA
| | - Luis Guanter
- Research Institute of Water and Environmental Engineering (IIAMA), Department of Applied Physics, Polytechnic University of Valencia, Valencia, Spain
| | - Alfredo R Huete
- School of Life Sciences, University of Technology Sydney, Sydney, New South Wales, Australia
| | - Jin Wu
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Jing M Chen
- Department of Geography and Planning, University of Toronto, Toronto, Ontario, Canada
| | - Weimin Ju
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, International Institute for Earth System Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
- Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural Resources, School of Geography and Ocean Science, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Josep Peñuelas
- CSIC, Global ecology Unit CREAF-CSIC-UAB, Bellaterra 08193, Catalonia, Spain
- CREAF, Cerdanyola del Vallès 08193, Catalonia, Spain
| | - Yongguang Zhang
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, International Institute for Earth System Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
- Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural Resources, School of Geography and Ocean Science, Nanjing University, Nanjing, Jiangsu 210023, China
- International Joint Carbon Neutrality Laboratory, Nanjing University, Nanjing, Jiangsu 210023 China
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16
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Shamekh S, Lamb KD, Huang Y, Gentine P. Implicit learning of convective organization explains precipitation stochasticity. Proc Natl Acad Sci U S A 2023; 120:e2216158120. [PMID: 37155849 DOI: 10.1073/pnas.2216158120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023] Open
Abstract
Accurate prediction of precipitation intensity is crucial for both human and natural systems, especially in a warming climate more prone to extreme precipitation. Yet, climate models fail to accurately predict precipitation intensity, particularly extremes. One missing piece of information in traditional climate model parameterizations is subgrid-scale cloud structure and organization, which affects precipitation intensity and stochasticity at coarse resolution. Here, using global storm-resolving simulations and machine learning, we show that, by implicitly learning subgrid organization, we can accurately predict precipitation variability and stochasticity with a low-dimensional set of latent variables. Using a neural network to parameterize coarse-grained precipitation, we find that the overall behavior of precipitation is reasonably predictable using large-scale quantities only; however, the neural network cannot predict the variability of precipitation (R2 ∼ 0.45) and underestimates precipitation extremes. The performance is significantly improved when the network is informed by our organization metric, correctly predicting precipitation extremes and spatial variability (R2 ∼ 0.9). The organization metric is implicitly learned by training the algorithm on a high-resolution precipitable water field, encoding the degree of subgrid organization. The organization metric shows large hysteresis, emphasizing the role of memory created by subgrid-scale structures. We demonstrate that this organization metric can be predicted as a simple memory process from information available at the previous time steps. These findings stress the role of organization and memory in accurate prediction of precipitation intensity and extremes and the necessity of parameterizing subgrid-scale convective organization in climate models to better project future changes of water cycle and extremes.
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Affiliation(s)
- Sara Shamekh
- Department of Earth of Environmental Engineering, Columbia University, New York, NY 10027
| | - Kara D Lamb
- Department of Earth of Environmental Engineering, Columbia University, New York, NY 10027
| | - Yu Huang
- Department of Earth of Environmental Engineering, Columbia University, New York, NY 10027
| | - Pierre Gentine
- Department of Earth of Environmental Engineering, Columbia University, New York, NY 10027
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17
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Zhu B, Deng Z, Song X, Zhao W, Huo D, Sun T, Ke P, Cui D, Lu C, Zhong H, Hong C, Qiu J, Davis SJ, Gentine P, Ciais P, Liu Z. CarbonMonitor-Power near-real-time monitoring of global power generation on hourly to daily scales. Sci Data 2023; 10:217. [PMID: 37069166 PMCID: PMC10108797 DOI: 10.1038/s41597-023-02094-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 03/20/2023] [Indexed: 04/19/2023] Open
Abstract
We constructed a frequently updated, near-real-time global power generation dataset: CarbonMonitor-Power since January, 2016 at national levels with near-global coverage and hourly-to-daily time resolution. The data presented here are collected from 37 countries across all continents for eight source groups, including three types of fossil sources (coal, gas, and oil), nuclear energy and four groups of renewable energy sources (solar energy, wind energy, hydro energy and other renewables including biomass, geothermal, etc.). The global near-real-time power dataset shows the dynamics of the global power system, including its hourly, daily, weekly and seasonal patterns as influenced by daily periodical activities, weekends, seasonal cycles, regular and irregular events (i.e., holidays) and extreme events (i.e., the COVID-19 pandemic). The CarbonMonitor-Power dataset reveals that the COVID-19 pandemic caused strong disruptions in some countries (i.e., China and India), leading to a temporary or long-lasting shift to low carbon intensity, while it had only little impact in some other countries (i.e., Australia). This dataset offers a large range of opportunities for power-related scientific research and policy-making.
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Affiliation(s)
- Biqing Zhu
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China
- Laboratoire des Sciences du Climate et de l'Environnement LSCE, Orme de Merisiers, 91191, Gif-sur-Yvette, France
| | - Zhu Deng
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China
- Product and Solution & Website Business Unit, Alibaba Cloud, Hangzhou, Zhejiang, 311121, China
| | - Xuanren Song
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China
| | - Wenli Zhao
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- Department Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Da Huo
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China
- Department of Civil & Mineral Engineering, University of Toronto, Toronto, ON, M5S 1A1, Canada
| | - Taochun Sun
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China
| | - Piyu Ke
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China
| | - Duo Cui
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China
| | - Chenxi Lu
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China
| | - Haiwang Zhong
- Department of Electrical Engineering, Sichuan Energy Internet Research Institute, Tsinghua University, Beijing, 100084, China
| | - Chaopeng Hong
- Institute of Environment and Ecology, Shenzhen International Graduate School, Tsinghua University, Shenzhen, China
| | - Jian Qiu
- Product and Solution & Website Business Unit, Alibaba Cloud, Hangzhou, Zhejiang, 311121, China
| | - Steven J Davis
- Department of Earth System Science, University of California, Irvine, 3232 Croul Hall, Irvine, CA, 92697-3100, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | - Philippe Ciais
- Laboratoire des Sciences du Climate et de l'Environnement LSCE, Orme de Merisiers, 91191, Gif-sur-Yvette, France.
| | - Zhu Liu
- Department of Earth System Science, Tsinghua University, Beijing, 100084, China.
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18
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Skulovich O, Gentine P. A Long-term Consistent Artificial Intelligence and Remote Sensing-based Soil Moisture Dataset. Sci Data 2023; 10:154. [PMID: 36949081 PMCID: PMC10033968 DOI: 10.1038/s41597-023-02053-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 03/07/2023] [Indexed: 03/24/2023] Open
Abstract
The Consistent Artificial Intelligence (AI)-based Soil Moisture (CASM) dataset is a global, consistent, and long-term, remote sensing soil moisture (SM) dataset created using machine learning. It is based on the NASA Soil Moisture Active Passive (SMAP) satellite mission SM data and is aimed at extrapolating SMAP-like quality SM back in time using previous satellite microwave platforms. CASM represents SM in the top soil layer, and it is defined on a global 25 km EASE-2 grid and for 2002-2020 with a 3-day temporal resolution. The seasonal cycle is removed for the neural network training to ensure its skill is targeted at predicting SM extremes. CASM comparison to 367 global in-situ SM monitoring sites shows a SMAP-like median correlation of 0.66. Additionally, the SM product uncertainty was assessed, and both aleatoric and epistemic uncertainties were estimated and included in the dataset. CASM dataset can be used to study a wide range of hydrological, carbon cycle, and energy processes since only a consistent long-term dataset allows assessing changes in water availability and water stress.
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Affiliation(s)
- Olya Skulovich
- Columbia University, Earth and Environmental Engineering Department, New York, NY, 10027, USA.
| | - Pierre Gentine
- Columbia University, Earth and Environmental Engineering Department, New York, NY, 10027, USA
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Grundner A, Beucler T, Gentine P, Iglesias‐Suarez F, Giorgetta MA, Eyring V. Deep Learning Based Cloud Cover Parameterization for ICON. J Adv Model Earth Syst 2022; 14:e2021MS002959. [PMID: 37035630 PMCID: PMC10078328 DOI: 10.1029/2021ms002959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 11/18/2022] [Accepted: 12/05/2022] [Indexed: 06/19/2023]
Abstract
A promising approach to improve cloud parameterizations within climate models and thus climate projections is to use deep learning in combination with training data from storm-resolving model (SRM) simulations. The ICOsahedral Non-hydrostatic (ICON) modeling framework permits simulations ranging from numerical weather prediction to climate projections, making it an ideal target to develop neural network (NN) based parameterizations for sub-grid scale processes. Within the ICON framework, we train NN based cloud cover parameterizations with coarse-grained data based on realistic regional and global ICON SRM simulations. We set up three different types of NNs that differ in the degree of vertical locality they assume for diagnosing cloud cover from coarse-grained atmospheric state variables. The NNs accurately estimate sub-grid scale cloud cover from coarse-grained data that has similar geographical characteristics as their training data. Additionally, globally trained NNs can reproduce sub-grid scale cloud cover of the regional SRM simulation. Using the game-theory based interpretability library SHapley Additive exPlanations, we identify an overemphasis on specific humidity and cloud ice as the reason why our column-based NN cannot perfectly generalize from the global to the regional coarse-grained SRM data. The interpretability tool also helps visualize similarities and differences in feature importance between regionally and globally trained column-based NNs, and reveals a local relationship between their cloud cover predictions and the thermodynamic environment. Our results show the potential of deep learning to derive accurate yet interpretable cloud cover parameterizations from global SRMs, and suggest that neighborhood-based models may be a good compromise between accuracy and generalizability.
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Affiliation(s)
- Arthur Grundner
- Deutsches Zentrum für Luft‐ und Raumfahrt e.V. (DLR)Institut für Physik der AtmosphäreOberpfaffenhofenGermany
- Center for Learning the Earth with Artificial Intelligence and Physics (LEAP)Columbia UniversityNew YorkNYUSA
| | - Tom Beucler
- Institute of Earth Surface DynamicsUniversity of LausanneLausanneSwitzerland
| | - Pierre Gentine
- Center for Learning the Earth with Artificial Intelligence and Physics (LEAP)Columbia UniversityNew YorkNYUSA
| | - Fernando Iglesias‐Suarez
- Deutsches Zentrum für Luft‐ und Raumfahrt e.V. (DLR)Institut für Physik der AtmosphäreOberpfaffenhofenGermany
| | | | - Veronika Eyring
- Deutsches Zentrum für Luft‐ und Raumfahrt e.V. (DLR)Institut für Physik der AtmosphäreOberpfaffenhofenGermany
- University of BremenInstitute of Environmental Physics (IUP)BremenGermany
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20
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Schiro KA, Su H, Ahmed F, Dai N, Singer CE, Gentine P, Elsaesser GS, Jiang JH, Choi YS, David Neelin J. Model spread in tropical low cloud feedback tied to overturning circulation response to warming. Nat Commun 2022; 13:7119. [DOI: 10.1038/s41467-022-34787-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 11/07/2022] [Indexed: 11/21/2022] Open
Abstract
AbstractAmong models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6), here we show that the magnitude of the tropical low cloud feedback, which contributes considerably to uncertainty in estimates of climate sensitivity, is intimately linked to tropical deep convection and its effects on the tropical atmospheric overturning circulation. First, a reduction in tropical ascent area and an increased frequency of heavy precipitation result in high cloud reduction and upper-tropospheric drying, which increases longwave cooling and reduces subsidence weakening, favoring low cloud reduction (Radiation-Subsidence Pathway). Second, increased longwave cooling decreases tropospheric stability, which also reduces subsidence weakening and low cloudiness (Stability-Subsidence Pathway). In summary, greater high cloud reduction and upper-tropospheric drying (negative longwave feedback) lead to a more positive cloud feedback among CMIP6 models by contributing to a greater reduction in low cloudiness (positive shortwave feedback). Varying strengths of the two pathways contribute considerably to the intermodel spread in climate sensitivity.
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21
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Fu Z, Ciais P, Feldman AF, Gentine P, Makowski D, Prentice IC, Stoy PC, Bastos A, Wigneron JP. Critical soil moisture thresholds of plant water stress in terrestrial ecosystems. Sci Adv 2022; 8:eabq7827. [PMID: 36332021 PMCID: PMC9635832 DOI: 10.1126/sciadv.abq7827] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
Plant water stress occurs at the point when soil moisture (SM) limits transpiration, defining a critical SM threshold (θcrit). Knowledge of the spatial distribution of θcrit is crucial for future projections of climate and water resources. Here, we use global eddy covariance observations to quantify θcrit and evaporative fraction (EF) regimes. Three canonical variables describe how EF is controlled by SM: the maximum EF (EFmax), θcrit, and slope (S) between EF and SM. We find systematic differences of these three variables across biomes. Variation in θcrit, S, and EFmax is mostly explained by soil texture, vapor pressure deficit, and precipitation, respectively, as well as vegetation structure. Dryland ecosystems tend to operate at low θcrit and show adaptation to water deficits. The negative relationship between θcrit and S indicates that dryland ecosystems minimize θcrit through mechanisms of sustained SM extraction and transport by xylem. Our results further suggest an optimal adaptation of local EF-SM response that maximizes growing-season evapotranspiration and photosynthesis.
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Affiliation(s)
- Zheng Fu
- Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Andrew F. Feldman
- NASA Goddard Space Flight Center, Earth Sciences Division, Greenbelt, MD 20771, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
| | - David Makowski
- Unit Applied Mathematics and Computer Science (UMR 518), INRAE, AgroParisTech, Université Paris-Saclay, Paris, France
| | - I. Colin Prentice
- Georgina Mace Centre for the Living Planet, Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot SL5 7PY, UK
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Paul C. Stoy
- Department of Biological Systems Engineering, University of Wisconsin–Madison, Madison, WI 53706, USA
| | - Ana Bastos
- Department Biogeochemical Integration, Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
| | - Jean-Pierre Wigneron
- ISPA, INRAE, Université de Bordeaux, Bordeaux Sciences Agro, F-33140 Villenave d’Ornon, France
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22
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Zhou S, Williams AP, Lintner BR, Findell KL, Keenan TF, Zhang Y, Gentine P. Diminishing seasonality of subtropical water availability in a warmer world dominated by soil moisture-atmosphere feedbacks. Nat Commun 2022; 13:5756. [PMID: 36180427 PMCID: PMC9525715 DOI: 10.1038/s41467-022-33473-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 09/20/2022] [Indexed: 11/25/2022] Open
Abstract
Global warming is expected to cause wet seasons to get wetter and dry seasons to get drier, which would have broad social and ecological implications. However, the extent to which this seasonal paradigm holds over land remains unclear. Here we examine seasonal changes in surface water availability (precipitation minus evaporation, P–E) from CMIP5 and CMIP6 projections. While the P–E seasonal cycle does broadly intensify over much of the land surface, ~20% of land area experiences a diminished seasonal cycle, mostly over subtropical regions and the Amazon. Using land–atmosphere coupling experiments, we demonstrate that 63% of the seasonality reduction is driven by seasonally varying soil moisture (SM) feedbacks on P–E. Declining SM reduces evapotranspiration and modulates circulation to enhance moisture convergence and increase P–E in the dry season but not in the wet season. Our results underscore the importance of SM–atmosphere feedbacks for seasonal water availability changes in a warmer climate. Here, the authors find increased dry–season and decreased wet–season water availability over subtropical regions and the Amazon. This is caused by seasonally varying soil moisture–atmosphere feedbacks under global warming.
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Affiliation(s)
- Sha Zhou
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, China. .,Institute of Land Surface Systems and Sustainable Development, Faculty of Geographical Science, Beijing Normal University, Beijing, China.
| | - A Park Williams
- Department of Geography, University of California, Los Angeles, CA, USA
| | - Benjamin R Lintner
- Department of Environmental Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Kirsten L Findell
- Geophysical Fluid Dynamics Laboratory, National Oceanic and Atmospheric Administration, Princeton, NJ, USA
| | - Trevor F Keenan
- Department of Environmental Science, Policy and Management, University of California, Berkeley, CA, USA.,Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Yao Zhang
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
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23
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Behrens G, Beucler T, Gentine P, Iglesias‐Suarez F, Pritchard M, Eyring V. Non-Linear Dimensionality Reduction With a Variational Encoder Decoder to Understand Convective Processes in Climate Models. J Adv Model Earth Syst 2022; 14:e2022MS003130. [PMID: 36245669 PMCID: PMC9541604 DOI: 10.1029/2022ms003130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 07/08/2022] [Accepted: 07/11/2022] [Indexed: 06/16/2023]
Abstract
Deep learning can accurately represent sub-grid-scale convective processes in climate models, learning from high resolution simulations. However, deep learning methods usually lack interpretability due to large internal dimensionality, resulting in reduced trustworthiness in these methods. Here, we use Variational Encoder Decoder structures (VED), a non-linear dimensionality reduction technique, to learn and understand convective processes in an aquaplanet superparameterized climate model simulation, where deep convective processes are simulated explicitly. We show that similar to previous deep learning studies based on feed-forward neural nets, the VED is capable of learning and accurately reproducing convective processes. In contrast to past work, we show this can be achieved by compressing the original information into only five latent nodes. As a result, the VED can be used to understand convective processes and delineate modes of convection through the exploration of its latent dimensions. A close investigation of the latent space enables the identification of different convective regimes: (a) stable conditions are clearly distinguished from deep convection with low outgoing longwave radiation and strong precipitation; (b) high optically thin cirrus-like clouds are separated from low optically thick cumulus clouds; and (c) shallow convective processes are associated with large-scale moisture content and surface diabatic heating. Our results demonstrate that VEDs can accurately represent convective processes in climate models, while enabling interpretability and better understanding of sub-grid-scale physical processes, paving the way to increasingly interpretable machine learning parameterizations with promising generative properties.
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Affiliation(s)
- Gunnar Behrens
- Deutsches Zentrum für Luft‐ und Raumfahrt (DLR)Institut für Physik der AtmosphäreOberpfaffenhofenGermany
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
| | - Tom Beucler
- Institute of Earth Surface DynamicsUniversity of LausanneLausanneSwitzerland
| | - Pierre Gentine
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
- Earth Institute and Data Science InstituteColumbia UniversityNew YorkNYUSA
| | - Fernando Iglesias‐Suarez
- Deutsches Zentrum für Luft‐ und Raumfahrt (DLR)Institut für Physik der AtmosphäreOberpfaffenhofenGermany
| | - Michael Pritchard
- Department of Earth System ScienceUniversity of California IrvineIrvineCAUSA
| | - Veronika Eyring
- Deutsches Zentrum für Luft‐ und Raumfahrt (DLR)Institut für Physik der AtmosphäreOberpfaffenhofenGermany
- University of BremenInstitute of Environmental Physics (IUP)BremenGermany
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24
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Lian X, Jeong S, Park CE, Xu H, Li LZX, Wang T, Gentine P, Peñuelas J, Piao S. Biophysical impacts of northern vegetation changes on seasonal warming patterns. Nat Commun 2022; 13:3925. [PMID: 35798743 PMCID: PMC9262912 DOI: 10.1038/s41467-022-31671-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 06/20/2022] [Indexed: 11/09/2022] Open
Abstract
The seasonal greening of Northern Hemisphere (NH) ecosystems, due to extended growing periods and enhanced photosynthetic activity, could modify near-surface warming by perturbing land-atmosphere energy exchanges, yet this biophysical control on warming seasonality is underexplored. By performing experiments with a coupled land-atmosphere model, here we show that summer greening effectively dampens NH warming by −0.15 ± 0.03 °C for 1982–2014 due to enhanced evapotranspiration. However, greening generates weak temperature changes in spring (+0.02 ± 0.06 °C) and autumn (−0.05 ± 0.05 °C), because the evaporative cooling is counterbalanced by radiative warming from albedo and water vapor feedbacks. The dwindling evaporative cooling towards cool seasons is also supported by state-of-the-art Earth system models. Moreover, greening-triggered energy imbalance is propagated forward by atmospheric circulation to subsequent seasons and causes sizable time-lagged climate effects. Overall, greening makes winter warmer and summer cooler, attenuating the seasonal amplitude of NH temperature. These findings demonstrate complex tradeoffs and linkages of vegetation-climate feedbacks among seasons. The seasonal greening of Northern Hemisphere ecosystems due to extended growing periods and enhanced photosynthetic activity is, via experiments, shown to modify near-surface warming by perturbing land-atmosphere energy exchanges.
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Affiliation(s)
- Xu Lian
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China.,Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | - Sujong Jeong
- Department of Environmental Planning, Graduate School of Environmental Studies, Seoul National University, Seoul, Republic of Korea. .,Environmental Planning Institute, Seoul National University, Seoul, Republic of Korea.
| | - Chang-Eui Park
- Center for Sustainable Environment Research, Korea Institute of Science and Technology, Seoul, Republic of Korea
| | - Hao Xu
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Laurent Z X Li
- Laboratoire de Météorologie Dynamique, CNRS, Sorbonne Université, Ecole Normale Supérieure, Ecole Polytechnique, Paris, France
| | - Tao Wang
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA.,Earth Institute, Columbia University, New York, NY, USA
| | - Josep Peñuelas
- CREAF, Cerdanyola del Valles, Barcelona, Catalonia, Spain.,CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra, Barcelona, Catalonia, Spain
| | - Shilong Piao
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China. .,State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China.
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25
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Green JK, Ballantyne A, Abramoff R, Gentine P, Makowski D, Ciais P. Surface temperatures reveal the patterns of vegetation water stress and their environmental drivers across the tropical Americas. Glob Chang Biol 2022; 28:2940-2955. [PMID: 35202508 DOI: 10.1111/gcb.16139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 02/08/2022] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
Vegetation is a key component in the global carbon cycle as it stores ~450 GtC as biomass, and removes about a third of anthropogenic CO2 emissions. However, in some regions, the rate of plant carbon uptake is beginning to slow, largely because of water stress. Here, we develop a new observation-based methodology to diagnose vegetation water stress and link it to environmental drivers. We used the ratio of remotely sensed land surface to near surface atmospheric temperatures (LST/Tair ) to represent vegetation water stress, and built regression tree models (random forests) to assess the relationship between LST/Tair and the main environmental drivers of surface energy fluxes in the tropical Americas. We further determined ecosystem traits associated with water stress and surface energy partitioning, pinpointed critical thresholds for water stress, and quantified changes in ecosystem carbon uptake associated with crossing these critical thresholds. We found that the top drivers of LST/Tair , explaining over a quarter of its local variability in the study region, are (1) radiation, in 58% of the study region; (2) water supply from precipitation, in 30% of the study region; and (3) atmospheric water demand from vapor pressure deficits (VPD), in 22% of the study region. Regions in which LST/Tair variation is driven by radiation are located in regions of high aboveground biomass or at high elevations, while regions in which LST/Tair is driven by water supply from precipitation or atmospheric demand tend to have low species richness. Carbon uptake by photosynthesis can be reduced by up to 80% in water-limited regions when critical thresholds for precipitation and air dryness are exceeded simultaneously, that is, as compound events. Our results demonstrate that vegetation structure and diversity can be important for regulating surface energy and carbon fluxes over tropical regions.
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Affiliation(s)
- Julia K Green
- Le Laboratoire des Sciences du Climat et de l'Environnement, CEA CNRS UVSQ, Gif sur Yvette, France
- The University of California, Berkeley, California, USA
| | - Ashley Ballantyne
- Le Laboratoire des Sciences du Climat et de l'Environnement, CEA CNRS UVSQ, Gif sur Yvette, France
- The University of Montana, Missoula, Montana, USA
| | - Rose Abramoff
- Le Laboratoire des Sciences du Climat et de l'Environnement, CEA CNRS UVSQ, Gif sur Yvette, France
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Pierre Gentine
- Columbia University, New York, New York, USA
- Earth Institute, Columbia University, New York, New York, USA
| | - David Makowski
- Institut National de la Recherche Agronomique, University Paris-Saclay, AgroParisTech, UMR 518 MIA, Paris, France
| | - Philippe Ciais
- Le Laboratoire des Sciences du Climat et de l'Environnement, CEA CNRS UVSQ, Gif sur Yvette, France
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26
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Fu Z, Ciais P, Prentice IC, Gentine P, Makowski D, Bastos A, Luo X, Green JK, Stoy PC, Yang H, Hajima T. Atmospheric dryness reduces photosynthesis along a large range of soil water deficits. Nat Commun 2022; 13:989. [PMID: 35190562 PMCID: PMC8861027 DOI: 10.1038/s41467-022-28652-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 01/28/2022] [Indexed: 12/13/2022] Open
Abstract
AbstractBoth low soil water content (SWC) and high atmospheric dryness (vapor pressure deficit, VPD) can negatively affect terrestrial gross primary production (GPP). The sensitivity of GPP to soil versus atmospheric dryness is difficult to disentangle, however, because of their covariation. Using global eddy-covariance observations, here we show that a decrease in SWC is not universally associated with GPP reduction. GPP increases in response to decreasing SWC when SWC is high and decreases only when SWC is below a threshold. By contrast, the sensitivity of GPP to an increase of VPD is always negative across the full SWC range. We further find canopy conductance decreases with increasing VPD (irrespective of SWC), and with decreasing SWC on drier soils. Maximum photosynthetic assimilation rate has negative sensitivity to VPD, and a positive sensitivity to decreasing SWC when SWC is high. Earth System Models underestimate the negative effect of VPD and the positive effect of SWC on GPP such that they should underestimate the GPP reduction due to increasing VPD in future climates.
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27
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Liu L, Chen X, Ciais P, Yuan W, Maignan F, Wu J, Piao S, Wang YP, Wigneron JP, Fan L, Gentine P, Yang X, Gong F, Liu H, Wang C, Tang X, Yang H, Ye Q, He B, Shang J, Su Y. Tropical tall forests are more sensitive and vulnerable to drought than short forests. Glob Chang Biol 2022; 28:1583-1595. [PMID: 34854168 DOI: 10.1111/gcb.16017] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 11/18/2021] [Accepted: 11/21/2021] [Indexed: 06/13/2023]
Abstract
Our limited understanding of the impacts of drought on tropical forests significantly impedes our ability in accurately predicting the impacts of climate change on this biome. Here, we investigated the impact of drought on the dynamics of forest canopies with different heights using time-series records of remotely sensed Ku-band vegetation optical depth (Ku-VOD), a proxy of top-canopy foliar mass and water content, and separated the signal of Ku-VOD changes into drought-induced reductions and subsequent non-drought gains. Both drought-induced reductions and non-drought increases in Ku-VOD varied significantly with canopy height. Taller tropical forests experienced greater relative Ku-VOD reductions during drought and larger non-drought increases than shorter forests, but the net effect of drought was more negative in the taller forests. Meta-analysis of in situ hydraulic traits supports the hypothesis that taller tropical forests are more vulnerable to drought stress due to smaller xylem-transport safety margins. Additionally, Ku-VOD of taller forests showed larger reductions due to increased atmospheric dryness, as assessed by vapor pressure deficit, and showed larger gains in response to enhanced water supply than shorter forests. Including the height-dependent variation of hydraulic transport in ecosystem models will improve the simulated response of tropical forests to drought.
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Affiliation(s)
- Liyang Liu
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou, China
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif sur Yvette, France
| | - Xiuzhi Chen
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif sur Yvette, France
| | - Wenping Yuan
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Fabienne Maignan
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif sur Yvette, France
| | - Jin Wu
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong
| | - Shilong Piao
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Ying-Ping Wang
- CSIRO Oceans and Atmosphere, Aspendale, Victoria, Australia
| | | | - Lei Fan
- Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station, School of Geographical Sciences, Southwest University, Chongqing, China
| | - Pierre Gentine
- Department of Earth & Environmental Engineering, Columbia University, New York, New York, USA
| | - Xueqin Yang
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou, China
| | - Fanxi Gong
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Hui Liu
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Chen Wang
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Xuli Tang
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Hui Yang
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif sur Yvette, France
| | - Qing Ye
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Bin He
- State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Global Change and Earth System Science, Beijing Normal University, Beijing, China
| | - Jiali Shang
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada
| | - Yongxian Su
- Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou, China
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28
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Dou X, Wang Y, Ciais P, Chevallier F, Davis SJ, Crippa M, Janssens-Maenhout G, Guizzardi D, Solazzo E, Yan F, Huo D, Zheng B, Zhu B, Cui D, Ke P, Sun T, Wang H, Zhang Q, Gentine P, Deng Z, Liu Z. Near-real-time global gridded daily CO 2 emissions. Innovation (N Y) 2022; 3:100182. [PMID: 34988539 PMCID: PMC8703084 DOI: 10.1016/j.xinn.2021.100182] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 10/28/2021] [Indexed: 11/26/2022] Open
Abstract
Precise and high-resolution carbon dioxide (CO2) emission data is of great importance in achieving carbon neutrality around the world. Here we present for the first time the near-real-time Global Gridded Daily CO2 Emissions Dataset (GRACED) from fossil fuel and cement production with a global spatial resolution of 0.1° by 0.1° and a temporal resolution of 1 day. Gridded fossil emissions are computed for different sectors based on the daily national CO2 emissions from near-real-time dataset (Carbon Monitor), the spatial patterns of point source emission dataset Global Energy Infrastructure Emissions Database (GID), Emission Database for Global Atmospheric Research (EDGAR), and spatiotemporal patters of satellite nitrogen dioxide (NO2) retrievals. Our study on the global CO2 emissions responds to the growing and urgent need for high-quality, fine-grained, near-real-time CO2 emissions estimates to support global emissions monitoring across various spatial scales. We show the spatial patterns of emission changes for power, industry, residential consumption, ground transportation, domestic and international aviation, and international shipping sectors from January 1, 2019, to December 31, 2020. This gives thorough insights into the relative contributions from each sector. Furthermore, it provides the most up-to-date and fine-grained overview of where and when fossil CO2 emissions have decreased and rebounded in response to emergencies (e.g., coronavirus disease 2019 [COVID-19]) and other disturbances of human activities of any previously published dataset. As the world recovers from the pandemic and decarbonizes its energy systems, regular updates of this dataset will enable policymakers to more closely monitor the effectiveness of climate and energy policies and quickly adapt.
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Affiliation(s)
- Xinyu Dou
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Yilong Wang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Frédéric Chevallier
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Steven J Davis
- Department of Earth System Science, University of California, Irvine, CA, USA
| | - Monica Crippa
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Diego Guizzardi
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Efisio Solazzo
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Feifan Yan
- Key Laboratory of Marine Environment and Ecology, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Da Huo
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Bo Zheng
- Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Biqing Zhu
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Duo Cui
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Piyu Ke
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Taochun Sun
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Hengqi Wang
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Qiang Zhang
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | - Zhu Deng
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Zhu Liu
- Department of Earth System Science, Tsinghua University, Beijing 100084, China
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29
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Konings AG, Saatchi SS, Frankenberg C, Keller M, Leshyk V, Anderegg WRL, Humphrey V, Matheny AM, Trugman A, Sack L, Agee E, Barnes ML, Binks O, Cawse‐Nicholson K, Christoffersen BO, Entekhabi D, Gentine P, Holtzman NM, Katul GG, Liu Y, Longo M, Martinez‐Vilalta J, McDowell N, Meir P, Mencuccini M, Mrad A, Novick KA, Oliveira RS, Siqueira P, Steele‐Dunne SC, Thompson DR, Wang Y, Wehr R, Wood JD, Xu X, Zuidema PA. Detecting forest response to droughts with global observations of vegetation water content. Glob Chang Biol 2021; 27:6005-6024. [PMID: 34478589 PMCID: PMC9293345 DOI: 10.1111/gcb.15872] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 08/23/2021] [Indexed: 05/11/2023]
Abstract
Droughts in a warming climate have become more common and more extreme, making understanding forest responses to water stress increasingly pressing. Analysis of water stress in trees has long focused on water potential in xylem and leaves, which influences stomatal closure and water flow through the soil-plant-atmosphere continuum. At the same time, changes of vegetation water content (VWC) are linked to a range of tree responses, including fluxes of water and carbon, mortality, flammability, and more. Unlike water potential, which requires demanding in situ measurements, VWC can be retrieved from remote sensing measurements, particularly at microwave frequencies using radar and radiometry. Here, we highlight key frontiers through which VWC has the potential to significantly increase our understanding of forest responses to water stress. To validate remote sensing observations of VWC at landscape scale and to better relate them to data assimilation model parameters, we introduce an ecosystem-scale analog of the pressure-volume curve, the non-linear relationship between average leaf or branch water potential and water content commonly used in plant hydraulics. The sources of variability in these ecosystem-scale pressure-volume curves and their relationship to forest response to water stress are discussed. We further show to what extent diel, seasonal, and decadal dynamics of VWC reflect variations in different processes relating the tree response to water stress. VWC can also be used for inferring belowground conditions-which are difficult to impossible to observe directly. Lastly, we discuss how a dedicated geostationary spaceborne observational system for VWC, when combined with existing datasets, can capture diel and seasonal water dynamics to advance the science and applications of global forest vulnerability to future droughts.
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Affiliation(s)
| | - Sassan S. Saatchi
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - Michael Keller
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
- United States Forest ServiceWashingtonDCUSA
| | | | | | | | | | - Anna Trugman
- University of California ‐ Santa BarbaraSanta BarbaraCAUSA
| | - Lawren Sack
- University of California ‐ Los AngelesLos AngelesCAUSA
| | | | | | - Oliver Binks
- The Australian National UniversityCanberraACTAustralia
| | | | | | | | | | | | | | | | - Marcos Longo
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Jordi Martinez‐Vilalta
- Centre de Recerca Ecològica i Aplicacions Forestals (CREAF)BarcelonaSpain
- Universitat Autònoma de BarcelonaBarcelonaSpain
| | - Nate McDowell
- Pacific Northwest National LaboratoryRichlandWAUSA
- Washington State UniversityPullmanWAUSA
| | - Patrick Meir
- The Australian National UniversityCanberraACTAustralia
- University of EdinburghEdinburghUK
| | - Maurizio Mencuccini
- Centre de Recerca Ecològica i Aplicacions Forestals (CREAF)BarcelonaSpain
- Institució Catalana de Recerca i Estudis Avançats (ICREA)BarcelonaSpain
| | - Assaad Mrad
- University of California ‐ IrvineIrvineCAUSA
| | | | | | | | | | - David R. Thompson
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Yujie Wang
- California Institute of TechnologyPasadenaCAUSA
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30
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Yang X, Wu J, Chen X, Ciais P, Maignan F, Yuan W, Piao S, Yang S, Gong F, Su Y, Dai Y, Liu L, Zhang H, Bonal D, Liu H, Chen G, Lu H, Wu S, Fan L, Gentine P, Wright SJ. A comprehensive framework for seasonal controls of leaf abscission and productivity in evergreen broadleaved tropical and subtropical forests. Innovation (N Y) 2021; 2:100154. [PMID: 34901903 PMCID: PMC8640595 DOI: 10.1016/j.xinn.2021.100154] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 08/18/2021] [Indexed: 11/16/2022] Open
Abstract
Relationships among productivity, leaf phenology, and seasonal variation in moisture and light availability are poorly understood for evergreen broadleaved tropical/subtropical forests, which contribute 25% of terrestrial productivity. On the one hand, as moisture availability declines, trees shed leaves to reduce transpiration and the risk of hydraulic failure. On the other hand, increases in light availability promote the replacement of senescent leaves to increase productivity. Here, we provide a comprehensive framework that relates the seasonality of climate, leaf abscission, and leaf productivity across the evergreen broadleaved tropical/subtropical forest biome. The seasonal correlation between rainfall and light availability varies from strongly negative to strongly positive across the tropics and maps onto the seasonal correlation between litterfall mass and productivity for 68 forests. Where rainfall and light covary positively, litterfall and productivity also covary positively and are always greater in the wetter sunnier season. Where rainfall and light covary negatively, litterfall and productivity are always greater in the drier and sunnier season if moisture supplies remain adequate; otherwise productivity is smaller in the drier sunnier season. This framework will improve the representation of tropical/subtropical forests in Earth system models and suggests how phenology and productivity will change as climate change alters the seasonality of cloud cover and rainfall across tropical/subtropical forests. Three climate-phenology regimes are identified across tropical and subtropical forest biomes Where light and water limit plant in dry season, litterfall and productivity peak in sunny wet season Where light or water alternately limits plant, productivity peaks in wet season with low litterfall Where water does not limit plant, litterfall and productivity peak in sunny dry season
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Affiliation(s)
- Xueqin Yang
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China.,Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Jianping Wu
- Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Xiuzhi Chen
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif sur Yvette, France
| | - Fabienne Maignan
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif sur Yvette, France
| | - Wenping Yuan
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Shilong Piao
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Song Yang
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Fanxi Gong
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China.,Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou 510070, China.,College of Earth Sciences, Chengdu University of Technology, Chengdu 610000, China
| | - Yongxian Su
- Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Yuhang Dai
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China.,Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou 510070, China.,College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510000, China
| | - Liyang Liu
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China.,Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou 510070, China.,Laboratoire des Sciences du Climat et de l'Environnement, IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif sur Yvette, France
| | - Haicheng Zhang
- Department of Geoscience, Environment & Society, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Damien Bonal
- INRA, UMR " Ecologie et Ecophysiologie Forestières", Université de Lorraine-INRA, 54280 Champenoux, France
| | - Hui Liu
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Guixing Chen
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Haibo Lu
- Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Shengbiao Wu
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong
| | - Lei Fan
- Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station, School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - Pierre Gentine
- Department of Earth & Environmental Engineering, Columbia University, New York, NY 10027, USA
| | - S Joseph Wright
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Panama
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31
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Frankenberg C, Yin Y, Byrne B, He L, Gentine P. Comment on "Recent global decline of CO 2 fertilization effects on vegetation photosynthesis". Science 2021; 373:eabg2947. [PMID: 34554806 DOI: 10.1126/science.abg2947] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Christian Frankenberg
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA.,Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Yi Yin
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - Brendan Byrne
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Liyin He
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Earth Institute, Columbia University, New York, NY, USA.,Data Science Institute, Columbia University, New York, NY, USA
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32
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Beucler T, Pritchard M, Rasp S, Ott J, Baldi P, Gentine P. Enforcing Analytic Constraints in Neural Networks Emulating Physical Systems. Phys Rev Lett 2021; 126:098302. [PMID: 33750168 DOI: 10.1103/physrevlett.126.098302] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 11/09/2020] [Accepted: 02/01/2021] [Indexed: 06/12/2023]
Abstract
Neural networks can emulate nonlinear physical systems with high accuracy, yet they may produce physically inconsistent results when violating fundamental constraints. Here, we introduce a systematic way of enforcing nonlinear analytic constraints in neural networks via constraints in the architecture or the loss function. Applied to convective processes for climate modeling, architectural constraints enforce conservation laws to within machine precision without degrading performance. Enforcing constraints also reduces errors in the subsets of the outputs most impacted by the constraints.
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Affiliation(s)
- Tom Beucler
- Department of Earth System Science, University of California, Irvine, California 92697-3100, USA
- Department of Earth and Environmental Engineering, Columbia University, New York, New York 10027, USA
| | - Michael Pritchard
- Department of Earth System Science, University of California, Irvine, California 92697-3100, USA
| | - Stephan Rasp
- Technical University of Munich, Boltzmannstr. 3 85748 Garching, Munich, Germany
| | - Jordan Ott
- Department of Computer Science, University of California, Irvine, California 92697, USA
| | - Pierre Baldi
- Department of Computer Science, University of California, Irvine, California 92697, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, New York 10027, USA
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33
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Chen C, Li D, Li Y, Piao S, Wang X, Huang M, Gentine P, Nemani RR, Myneni RB. Biophysical impacts of Earth greening largely controlled by aerodynamic resistance. Sci Adv 2020; 6:6/47/eabb1981. [PMID: 33219018 PMCID: PMC7679158 DOI: 10.1126/sciadv.abb1981] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 10/07/2020] [Indexed: 05/19/2023]
Abstract
Satellite observations show widespread increasing trends of leaf area index (LAI), known as the Earth greening. However, the biophysical impacts of this greening on land surface temperature (LST) remain unclear. Here, we quantify the biophysical impacts of Earth greening on LST from 2000 to 2014 and disentangle the contributions of different factors using a physically based attribution model. We find that 93% of the global vegetated area shows negative sensitivity of LST to LAI increase at the annual scale, especially for semiarid woody vegetation. Further considering the LAI trends (P ≤ 0.1), 30% of the global vegetated area is cooled by these trends and 5% is warmed. Aerodynamic resistance is the dominant factor in controlling Earth greening's biophysical impacts: The increase in LAI produces a decrease in aerodynamic resistance, thereby favoring increased turbulent heat transfer between the land and the atmosphere, especially latent heat flux.
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Affiliation(s)
- Chi Chen
- Department of Earth and Environment, Boston University, Boston, MA 02215, USA.
| | - Dan Li
- Department of Earth and Environment, Boston University, Boston, MA 02215, USA.
| | - Yue Li
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Shilong Piao
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Xuhui Wang
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Maoyi Huang
- Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA 99352, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
| | | | - Ranga B Myneni
- Department of Earth and Environment, Boston University, Boston, MA 02215, USA
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34
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Green JK, Berry J, Ciais P, Zhang Y, Gentine P. Amazon rainforest photosynthesis increases in response to atmospheric dryness. Sci Adv 2020; 6:6/47/eabb7232. [PMID: 33219023 PMCID: PMC7679161 DOI: 10.1126/sciadv.abb7232] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 10/07/2020] [Indexed: 05/19/2023]
Abstract
Earth system models predict that increases in atmospheric and soil dryness will reduce photosynthesis in the Amazon rainforest, with large implications for the global carbon cycle. Using in situ observations, solar-induced fluorescence, and nonlinear machine learning techniques, we show that, in reality, this is not necessarily the case: In many of the wettest parts of this region, photosynthesis and biomass tend to increase with increased atmospheric dryness, despite the associated reductions in canopy conductance to CO2 These results can be largely explained by changes in canopy properties, specifically, new leaves flushed during the dry season have higher photosynthetic capacity than the leaves they replace, compensating for the negative stomatal response to increased dryness. As atmospheric dryness will increase with climate change, our study highlights the importance of reframing how we represent the response of ecosystem photosynthesis to atmospheric dryness in very wet regions, to accurately quantify the land carbon sink.
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Affiliation(s)
- J K Green
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA.
- Laboratoire des Sciences du Climat et de l'Environnement (LSCE), Gif-sur-Yvette, France
| | - J Berry
- Carnegie Institution for Science, Stanford, CA, USA
| | - P Ciais
- Laboratoire des Sciences du Climat et de l'Environnement (LSCE), Gif-sur-Yvette, France
| | - Y Zhang
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- Department of Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - P Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- The Earth Institute, Columbia University, New York, NY, USA
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35
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Guérin M, von Arx G, Martin-Benito D, Andreu-Hayles L, Griffin KL, McDowell NG, Pockman W, Gentine P. Distinct xylem responses to acute vs prolonged drought in pine trees. Tree Physiol 2020; 40:605-620. [PMID: 31976523 DOI: 10.1093/treephys/tpz144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 09/17/2019] [Accepted: 12/23/2019] [Indexed: 06/10/2023]
Abstract
Increasing dryness challenges trees' ability to maintain water transport to the leaves. Most plant hydraulics models use a static xylem response to water stress. Yet, in reality, lower soil moisture and warmer temperatures during growing seasons feed back onto xylem development. In turn, adjustments to water stress in the newly built xylem influence future physiological responses to droughts. In this study, we investigate the annual variation of anatomical traits in branch xylem in response to different soil and atmospheric moisture conditions and tree stress levels, as indicated by seasonal predawn leaf water potential (ΨL,pd). We used a 6-year field experiment in southwestern USA with three soil water treatments applied to Pinus edulis Engelm trees-ambient, drought (45% rain reduction) and irrigation (15-35% annual water addition). All trees were also subject to a natural 1-year acute drought (soil and atmospheric) that occurred during the experiment. The irrigated trees showed only moderate changes in anatomy-derived hydraulic traits compared with the ambient trees, suggesting a generally stable, well-balanced xylem structure under unstressed conditions. The artificial prolonged soil drought increased hydraulic efficiency but lowered xylem construction costs and decreased tracheid implosion safety ((t/b)2), suggesting that annual adjustments of xylem structure follow a safety-efficiency trade-off. The acute drought plunged hydraulic efficiency across all treatments. The combination of acute and prolonged drought resulted in vulnerable and inefficient new xylem, disrupting the stability of the anatomical trade-off observed in the rest of the years. The xylem hydraulic traits showed no consistent direct link to ΨL,pd. In the future, changes in seasonality of soil and atmospheric moisture are likely to have a critical impact on the ability of P. edulis to acclimate its xylem to warmer climate. Furthermore, the increasing frequency of acute droughts might reduce hydraulic resilience of P. edulis by repeatedly creating vulnerable and less efficient anatomical structure.
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Affiliation(s)
- Marceau Guérin
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
| | - Georg von Arx
- Forest Dynamics Research Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111 CH-8903 Birmensdorf, Switzerland
| | - Dario Martin-Benito
- INIA, CIFOR, Ctra La Coruña km 7.5, 28040 Madrid, Spain
- Forest Ecology, Department of Environmental Sciences, Swiss Federal Institute of Technology, ETH Zurich, Universitätstrasse 16, 8092 Zürich, Switzerland
| | - Laia Andreu-Hayles
- Tree-Ring Laboratory, Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9 W, Palisades, NY 10964, USA
| | - Kevin L Griffin
- Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
| | - Nate G McDowell
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA 99354, USA
| | - William Pockman
- Biology Department, MSC03 202, University of New Mexico, Albuquerque, NM 87131, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
- Earth Institute, Columbia University, Hogan Hall, 2910 Broadway, New York, NY 10027, USA
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36
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Clifton OE, Fiore AM, Massman WJ, Baublitz CB, Coyle M, Emberson L, Fares S, Farmer DK, Gentine P, Gerosa G, Guenther AB, Helmig D, Lombardozzi DL, Munger JW, Patton EG, Pusede SE, Schwede DB, Silva SJ, Sörgel M, Steiner AL, Tai APK. Dry Deposition of Ozone over Land: Processes, Measurement, and Modeling. Rev Geophys 2020; 58:10.1029/2019RG000670. [PMID: 33748825 PMCID: PMC7970530 DOI: 10.1029/2019rg000670] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 01/24/2020] [Indexed: 05/21/2023]
Abstract
Dry deposition of ozone is an important sink of ozone in near surface air. When dry deposition occurs through plant stomata, ozone can injure the plant, altering water and carbon cycling and reducing crop yields. Quantifying both stomatal and nonstomatal uptake accurately is relevant for understanding ozone's impact on human health as an air pollutant and on climate as a potent short-lived greenhouse gas and primary control on the removal of several reactive greenhouse gases and air pollutants. Robust ozone dry deposition estimates require knowledge of the relative importance of individual deposition pathways, but spatiotemporal variability in nonstomatal deposition is poorly understood. Here we integrate understanding of ozone deposition processes by synthesizing research from fields such as atmospheric chemistry, ecology, and meteorology. We critically review methods for measurements and modeling, highlighting the empiricism that underpins modeling and thus the interpretation of observations. Our unprecedented synthesis of knowledge on deposition pathways, particularly soil and leaf cuticles, reveals process understanding not yet included in widely-used models. If coordinated with short-term field intensives, laboratory studies, and mechanistic modeling, measurements from a few long-term sites would bridge the molecular to ecosystem scales necessary to establish the relative importance of individual deposition pathways and the extent to which they vary in space and time. Our recommended approaches seek to close knowledge gaps that currently limit quantifying the impact of ozone dry deposition on air quality, ecosystems, and climate.
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Affiliation(s)
| | - Arlene M Fiore
- Department of Earth and Environmental Sciences, Columbia University, and Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA
| | - William J Massman
- USDA Forest Service, Rocky Mountain Research Station, Fort Collins, CO, USA
| | - Colleen B Baublitz
- Department of Earth and Environmental Sciences, Columbia University, and Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA
| | - Mhairi Coyle
- Centre for Ecology and Hydrology, Edinburgh, Bush Estate, Penicuik, Midlothian, UK and The James Hutton Institute, Craigibuckler, Aberdeen, UK
| | - Lisa Emberson
- Stockholm Environment Institute, Environment Department, University of York, York, UK
| | - Silvano Fares
- Council of Agricultural Research and Economics, Research Centre for Forestry and Wood, and National Research Council, Institute of Bioeconomy, Rome, Italy
| | - Delphine K Farmer
- Department of Chemistry, Colorado State University, Fort Collins, CO, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | - Giacomo Gerosa
- Dipartimento di Matematica e Fisica, Università Cattolica del S. C., Brescia, Italy
| | - Alex B Guenther
- Department of Earth System Science, University of California, Irvine, CA, USA
| | - Detlev Helmig
- Institute of Alpine and Arctic Research, University of Colorado at Boulder, Boulder, CO, USA
| | | | - J William Munger
- School of Engineering and Applied Sciences and Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | | | - Sally E Pusede
- Department of Environmental Sciences, University of Virginia, Charlottesville, VA, USA
| | - Donna B Schwede
- U.S. Environmental Protection Agency, National Exposure Research Laboratory, Research Triangle Park, NC, USA
| | - Sam J Silva
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Matthias Sörgel
- Max Plank Institute for Chemistry, Atmospheric Chemistry Department, Mainz, Germany
| | - Allison L Steiner
- Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Amos P K Tai
- Earth System Science Programme, Faculty of Science, and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong SAR, China
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37
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Yin J, Gentine P, Guo S, Zhou S, Sullivan SC, Zhang Y, Gu L, Liu P. Reply to 'Increases in temperature do not translate to increased flooding'. Nat Commun 2019; 10:5675. [PMID: 31831747 PMCID: PMC6908579 DOI: 10.1038/s41467-019-13613-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 11/11/2019] [Indexed: 11/09/2022] Open
Affiliation(s)
- Jiabo Yin
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA.
- Earth Institute, Columbia University, New York, NY, 10025, USA.
| | - Shenglian Guo
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China.
| | - Sha Zhou
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
- Earth Institute, Columbia University, New York, NY, 10025, USA
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, NY, 10964, USA
| | - Sylvia C Sullivan
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Yao Zhang
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Lei Gu
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China
| | - Pan Liu
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China.
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38
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Massmann A, Gentine P, Lin C. When Does Vapor Pressure Deficit Drive or Reduce Evapotranspiration? J Adv Model Earth Syst 2019; 11:3305-3320. [PMID: 31894191 PMCID: PMC6919419 DOI: 10.1029/2019ms001790] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/06/2019] [Accepted: 09/12/2019] [Indexed: 05/30/2023]
Abstract
Increasing vapor pressure deficit (VPD) increases atmospheric demand for water. While increased evapotranspiration (ET) in response to increased atmospheric demand seems intuitive, plants are capable of reducing ET in response to increased VPD by closing their stomata. We examine which effect dominates the response to increasing VPD: atmospheric demand and increases in ET or plant response (stomata closure) and decreases in ET. We use Penman-Monteith, combined with semiempirical optimal stomatal regulation theory and underlying water use efficiency, to develop a theoretical framework for assessing ET response to VPD. The theory suggests that depending on the environment and plant characteristics, ET response to increasing VPD can vary from strongly decreasing to increasing, highlighting the diversity of plant water regulation strategies. The ET response varies due to (1) climate, with tropical and temperate climates more likely to exhibit a positive ET response to increasing VPD than boreal and arctic climates; (2) photosynthesis strategy, with C3 plants more likely to exhibit a positive ET response than C4 plants; and (3) plant type, with crops more likely to exhibit a positive ET response, and shrubs and gymniosperm trees more likely to exhibit a negative ET response. These results, derived from previous literature connecting plant parameters to plant and climate characteristics, highlight the utility of our simplified framework for understanding complex land-atmosphere systems in terms of idealized scenarios in which ET responds to VPD only. This response is otherwise challenging to assess in an environment where many processes coevolve together.
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Affiliation(s)
- Adam Massmann
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
| | - Pierre Gentine
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
| | - Changjie Lin
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
- State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic EngineeringTsinghua UniversityBeijingChina
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39
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Massmann A, Gentine P, Lin C. When Does Vapor Pressure Deficit Drive or Reduce Evapotranspiration? J Adv Model Earth Syst 2019; 11:3305-3320. [PMID: 31894191 DOI: 10.5194/hess-2018-553] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/06/2019] [Accepted: 09/12/2019] [Indexed: 05/24/2023]
Abstract
Increasing vapor pressure deficit (VPD) increases atmospheric demand for water. While increased evapotranspiration (ET) in response to increased atmospheric demand seems intuitive, plants are capable of reducing ET in response to increased VPD by closing their stomata. We examine which effect dominates the response to increasing VPD: atmospheric demand and increases in ET or plant response (stomata closure) and decreases in ET. We use Penman-Monteith, combined with semiempirical optimal stomatal regulation theory and underlying water use efficiency, to develop a theoretical framework for assessing ET response to VPD. The theory suggests that depending on the environment and plant characteristics, ET response to increasing VPD can vary from strongly decreasing to increasing, highlighting the diversity of plant water regulation strategies. The ET response varies due to (1) climate, with tropical and temperate climates more likely to exhibit a positive ET response to increasing VPD than boreal and arctic climates; (2) photosynthesis strategy, with C3 plants more likely to exhibit a positive ET response than C4 plants; and (3) plant type, with crops more likely to exhibit a positive ET response, and shrubs and gymniosperm trees more likely to exhibit a negative ET response. These results, derived from previous literature connecting plant parameters to plant and climate characteristics, highlight the utility of our simplified framework for understanding complex land-atmosphere systems in terms of idealized scenarios in which ET responds to VPD only. This response is otherwise challenging to assess in an environment where many processes coevolve together.
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Affiliation(s)
- Adam Massmann
- Department of Earth and Environmental Engineering Columbia University New York NY USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering Columbia University New York NY USA
| | - Changjie Lin
- Department of Earth and Environmental Engineering Columbia University New York NY USA
- State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic Engineering Tsinghua University Beijing China
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40
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Zhou S, Williams AP, Berg AM, Cook BI, Zhang Y, Hagemann S, Lorenz R, Seneviratne SI, Gentine P. Land-atmosphere feedbacks exacerbate concurrent soil drought and atmospheric aridity. Proc Natl Acad Sci U S A 2019; 116:18848-18853. [PMID: 31481606 PMCID: PMC6754607 DOI: 10.1073/pnas.1904955116] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Compound extremes such as cooccurring soil drought (low soil moisture) and atmospheric aridity (high vapor pressure deficit) can be disastrous for natural and societal systems. Soil drought and atmospheric aridity are 2 main physiological stressors driving widespread vegetation mortality and reduced terrestrial carbon uptake. Here, we empirically demonstrate that strong negative coupling between soil moisture and vapor pressure deficit occurs globally, indicating high probability of cooccurring soil drought and atmospheric aridity. Using the Global Land Atmosphere Coupling Experiment (GLACE)-CMIP5 experiment, we further show that concurrent soil drought and atmospheric aridity are greatly exacerbated by land-atmosphere feedbacks. The feedback of soil drought on the atmosphere is largely responsible for enabling atmospheric aridity extremes. In addition, the soil moisture-precipitation feedback acts to amplify precipitation and soil moisture deficits in most regions. CMIP5 models further show that the frequency of concurrent soil drought and atmospheric aridity enhanced by land-atmosphere feedbacks is projected to increase in the 21st century. Importantly, land-atmosphere feedbacks will greatly increase the intensity of both soil drought and atmospheric aridity beyond that expected from changes in mean climate alone.
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Affiliation(s)
- Sha Zhou
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964;
- Earth Institute, Columbia University, New York, NY 10027
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027
| | - A Park Williams
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964
| | - Alexis M Berg
- Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544
| | - Benjamin I Cook
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964
- NASA Goddard Institute for Space Studies, New York, NY 10027
| | - Yao Zhang
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027
| | - Stefan Hagemann
- Helmholtz-Zentrum Geesthacht, Institute of Coastal Research, 21502 Geesthacht, Germany
| | - Ruth Lorenz
- Institute for Atmospheric and Climate Science, Eidgenössische Technische Hochschule Zürich, 8092 Zürich, Switzerland
| | - Sonia I Seneviratne
- Institute for Atmospheric and Climate Science, Eidgenössische Technische Hochschule Zürich, 8092 Zürich, Switzerland
| | - Pierre Gentine
- Earth Institute, Columbia University, New York, NY 10027
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027
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41
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Barros FDV, Bittencourt PRL, Brum M, Restrepo-Coupe N, Pereira L, Teodoro GS, Saleska SR, Borma LS, Christoffersen BO, Penha D, Alves LF, Lima AJN, Carneiro VMC, Gentine P, Lee JE, Aragão LEOC, Ivanov V, Leal LSM, Araujo AC, Oliveira RS. Hydraulic traits explain differential responses of Amazonian forests to the 2015 El Niño-induced drought. New Phytol 2019; 223:1253-1266. [PMID: 31077396 DOI: 10.1111/nph.15909] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 04/28/2019] [Indexed: 05/12/2023]
Abstract
Reducing uncertainties in the response of tropical forests to global change requires understanding how intra- and interannual climatic variability selects for different species, community functional composition and ecosystem functioning, so that the response to climatic events of differing frequency and severity can be predicted. Here we present an extensive dataset of hydraulic traits of dominant species in two tropical Amazon forests with contrasting precipitation regimes - low seasonality forest (LSF) and high seasonality forest (HSF) - and relate them to community and ecosystem response to the El Niño-Southern Oscillation (ENSO) of 2015. Hydraulic traits indicated higher drought tolerance in the HSF than in the LSF. Despite more intense drought and lower plant water potentials in HSF during the 2015-ENSO, greater xylem embolism resistance maintained similar hydraulic safety margin as in LSF. This likely explains how ecosystem-scale whole-forest canopy conductance at HSF maintained a similar response to atmospheric drought as at LSF, despite their water transport systems operating at different water potentials. Our results indicate that contrasting precipitation regimes (at seasonal and interannual time scales) select for assemblies of hydraulic traits and taxa at the community level, which may have a significant role in modulating forest drought response at ecosystem scales.
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Affiliation(s)
- Fernanda de V Barros
- Department of Plant Biology, Institute of Biology, CP 6109, University of Campinas- UNICAMP, Campinas, SP, 13083-970, Brazil
| | - Paulo R L Bittencourt
- Department of Plant Biology, Institute of Biology, CP 6109, University of Campinas- UNICAMP, Campinas, SP, 13083-970, Brazil
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK
| | - Mauro Brum
- Department of Plant Biology, Institute of Biology, CP 6109, University of Campinas- UNICAMP, Campinas, SP, 13083-970, Brazil
| | - Natalia Restrepo-Coupe
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
- School of Life Science, University of Technology Sydney, Sydney, NSW, 2006, Australia
| | - Luciano Pereira
- Department of Plant Biology, Institute of Biology, CP 6109, University of Campinas- UNICAMP, Campinas, SP, 13083-970, Brazil
| | - Grazielle S Teodoro
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, 66075-110, Brazil
| | - Scott R Saleska
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
| | - Laura S Borma
- Earth System Science Centre, National Institute for Space Research, Av. dos Astronautas, 1.758, São José dos Campos, SP, 12227-010, Brazil
| | - Bradley O Christoffersen
- Department of Biology and School of Earth, Environmental and Marine Sciences, University of Texas Rio Grande Valley, Edinburg, TX, 78539, USA
| | - Deliane Penha
- Society, Nature and Development Department, Federal University of Western Pará (UFOPA), Santarém, PA, 68035-110, Brazil
| | - Luciana F Alves
- Center for Tropical Research, Institute of the Environment and Sustainability, University of California - Los Angeles, Los Angeles, CA, 90095, USA
| | - Adriano J N Lima
- Laboratório de Manejo Florestal, Instituto Nacional de Pesquisas na Amazônia - INPA, Manaus, AM, 69.067-375, Brazil
| | - Vilany M C Carneiro
- Laboratório de Manejo Florestal, Instituto Nacional de Pesquisas na Amazônia - INPA, Manaus, AM, 69.067-375, Brazil
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Jung-Eun Lee
- Department of Earth and Planetary Sciences, Brown University Providence, 324 Brook Street, Providence, RI, 02912, USA
| | - Luiz E O C Aragão
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK
- Remote Sensing Division, National Institute for Space Research, Av. dos Astronautas, 1.758, São José dos Campos, SP, 12227-010, Brazil
| | - Valeriy Ivanov
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI, 48019, USA
| | - Leila S M Leal
- Laboratory of Sustainable Systems Analyses, Oriental Amazon Embrapa, Belém, Pará, 66083-156, Brazil
| | - Alessandro C Araujo
- LBA Program Micrometeorology Group, INPA, Manaus, Amazonas, 69.067-375, Brazil
| | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, CP 6109, University of Campinas- UNICAMP, Campinas, SP, 13083-970, Brazil
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42
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Novick KA, Konings AG, Gentine P. Beyond soil water potential: An expanded view on isohydricity including land-atmosphere interactions and phenology. Plant Cell Environ 2019; 42:1802-1815. [PMID: 30632172 DOI: 10.1111/pce.13517] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 01/02/2019] [Accepted: 01/07/2019] [Indexed: 05/21/2023]
Abstract
Over the past decade, the concept of isohydry or anisohydry, which describes the link between soil water potential (ΨS ), leaf water potential (ΨL ), and stomatal conductance (gs ), has soared in popularity. However, its utility has recently been questioned, and a surprising lack of coordination between the dynamics of ΨL and gs across biomes has been reported. Here, we offer a more expanded view of the isohydricity concept that considers effects of vapour pressure deficit (VPD) and leaf area index (AL ) on the apparent sensitivities of ΨL and gs to drought. After validating the model with tree- and ecosystem-scale data, we find that within a site, isohydricity is a strong predictor of limitations to stomatal function, though variation in VPD and leaf area, among other factors, can challenge its diagnosis. Across sites, the theory predicts that the degree of isohydricity is a good predictor of the sensitivity of gs to declining soil water in the absence of confounding effects from other drivers. However, if VPD effects are significant, they alone are sufficient to decouple the dynamics of ΨL and gs entirely. We conclude with a set of practical recommendations for future applications of the isohydricity framework within and across sites.
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Affiliation(s)
- Kimberly A Novick
- School of Public and Environmental Affairs, Indiana University Bloomington, Bloomington, Indiana
| | - Alexandra G Konings
- Department of Earth System Science, Stanford University, Stanford, California
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, New York
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43
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Miralles DG, Gentine P, Seneviratne SI, Teuling AJ. Cover Image, Volume 1436, Issue 1. Ann N Y Acad Sci 2019. [DOI: 10.1111/nyas.14024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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44
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Miralles DG, Gentine P, Seneviratne SI, Teuling AJ. Land-atmospheric feedbacks during droughts and heatwaves: state of the science and current challenges. Ann N Y Acad Sci 2019; 1436:19-35. [PMID: 29943456 PMCID: PMC6378599 DOI: 10.1111/nyas.13912] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 05/29/2018] [Accepted: 06/01/2018] [Indexed: 11/30/2022]
Abstract
Droughts and heatwaves cause agricultural loss, forest mortality, and drinking water scarcity, especially when they occur simultaneously as combined events. Their predicted increase in recurrence and intensity poses serious threats to future food security. Still today, the knowledge of how droughts and heatwaves start and evolve remains limited, and so does our understanding of how climate change may affect them. Droughts and heatwaves have been suggested to intensify and propagate via land-atmosphere feedbacks. However, a global capacity to observe these processes is still lacking, and climate and forecast models are immature when it comes to representing the influences of land on temperature and rainfall. Key open questions remain in our goal to uncover the real importance of these feedbacks: What is the impact of the extreme meteorological conditions on ecosystem evaporation? How do these anomalies regulate the atmospheric boundary layer state (event self-intensification) and contribute to the inflow of heat and moisture to other regions (event self-propagation)? Can this knowledge on the role of land feedbacks, when available, be exploited to develop geo-engineering mitigation strategies that prevent these events from aggravating during their early stages? The goal of our perspective is not to present a convincing answer to these questions, but to assess the scientific progress to date, while highlighting new and innovative avenues to keep advancing our understanding in the future.
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Affiliation(s)
- Diego G. Miralles
- Laboratory of Hydrology and Water ManagementGhent UniversityGhentBelgium
| | - Pierre Gentine
- Earth and Environmental EngineeringColumbia UniversityNew YorkNew York
| | | | - Adriaan J. Teuling
- Hydrology and Quantitative Water Management GroupWageningen University and ResearchWageningenthe Netherlands
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45
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Green JK, Seneviratne SI, Berg AM, Findell KL, Hagemann S, Lawrence DM, Gentine P. Large influence of soil moisture on long-term terrestrial carbon uptake. Nature 2019; 565:476-479. [PMID: 30675043 PMCID: PMC6355256 DOI: 10.1038/s41586-018-0848-x] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 11/21/2018] [Indexed: 11/28/2022]
Abstract
Although the terrestrial biosphere absorbs about 25 per cent of anthropogenic carbon dioxide (CO2) emissions, the rate of land carbon uptake remains highly uncertain, leading to uncertainties in climate projections1,2. Understanding the factors that limit or drive land carbon storage is therefore important for improving climate predictions. One potential limiting factor for land carbon uptake is soil moisture, which can reduce gross primary production through ecosystem water stress3,4, cause vegetation mortality5 and further exacerbate climate extremes due to land-atmosphere feedbacks6. Previous work has explored the impact of soil-moisture availability on past carbon-flux variability3,7,8. However, the influence of soil-moisture variability and trends on the long-term carbon sink and the mechanisms responsible for associated carbon losses remain uncertain. Here we use the data output from four Earth system models9 from a series of experiments to analyse the responses of terrestrial net biome productivity to soil-moisture changes, and find that soil-moisture variability and trends induce large CO2 fluxes (about two to three gigatons of carbon per year; comparable with the land carbon sink itself1) throughout the twenty-first century. Subseasonal and interannual soil-moisture variability generate CO2 as a result of the nonlinear response of photosynthesis and net ecosystem exchange to soil-water availability and of the increased temperature and vapour pressure deficit caused by land-atmosphere interactions. Soil-moisture variability reduces the present land carbon sink, and its increase and drying trends in several regions are expected to reduce it further. Our results emphasize that the capacity of continents to act as a future carbon sink critically depends on the nonlinear response of carbon fluxes to soil moisture and on land-atmosphere interactions. This suggests that the increasing trend in carbon uptake rate may not be sustained past the middle of the century and could result in accelerated atmospheric CO2 growth.
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Affiliation(s)
- Julia K Green
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA.
| | - Sonia I Seneviratne
- Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
| | - Alexis M Berg
- Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ, USA
| | | | - Stefan Hagemann
- Institute of Coastal Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany
| | - David M Lawrence
- Climate and Global Dynamics Laboratory, Terrestrial Sciences, National Center for Atmospheric Research, Boulder, CO, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- The Earth Institute, Columbia University, New York, NY, USA
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46
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Zhou S, Zhang Y, Park Williams A, Gentine P. Projected increases in intensity, frequency, and terrestrial carbon costs of compound drought and aridity events. Sci Adv 2019; 5:eaau5740. [PMID: 30746452 PMCID: PMC6357735 DOI: 10.1126/sciadv.aau5740] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 12/10/2018] [Indexed: 05/05/2023]
Abstract
Drought and atmospheric aridity pose large risks to ecosystem services and agricultural production. However, these factors are seldom assessed together as compound events, although they often occur simultaneously. Drought stress on terrestrial carbon uptake is characterized by soil moisture (SM) deficit and high vapor pressure deficit (VPD). We used in situ observations and 15 Earth system models to show that compound events with very high VPD and low SM occur more frequently than expected if these events were independent. These compound events are projected to become more frequent and more extreme and exert increasingly negative effects on continental productivity. Models project intensified negative effects of high VPD and low SM on vegetation productivity, with the intensification of SM exceeding those of VPD in the Northern Hemisphere. These results highlight the importance of compound extreme events and their threats for the capability of continents to act as a carbon sink.
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Affiliation(s)
- Sha Zhou
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
| | - Yao Zhang
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
| | - A. Park Williams
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
- Earth Institute, Columbia University, New York, NY 10027, USA
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47
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Zhang Y, Joiner J, Gentine P, Zhou S. Reduced solar-induced chlorophyll fluorescence from GOME-2 during Amazon drought caused by dataset artifacts. Glob Chang Biol 2018; 24:2229-2230. [PMID: 29573512 DOI: 10.1111/gcb.14134] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 03/09/2018] [Indexed: 05/21/2023]
Abstract
Recently, Yang et al. () reported a decrease in solar-induced chlorophyll fluorescence (SIF) during 2015/2016 El Niño event albeit the increase in enhanced vegetation index (EVI). They interpreted the reduced SIF as a signal of reduced ecosystem photosynthesis. However, we argue that the reduced SIF during 2015/2016 is caused by a decreasing trend of SIF due to sensor degradation and the satellite overpass time is critical for drought impact assessment.
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Affiliation(s)
- Yao Zhang
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | - Joana Joiner
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | - Sha Zhou
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
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48
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Lemordant L, Gentine P, Swann AS, Cook BI, Scheff J. Critical impact of vegetation physiology on the continental hydrologic cycle in response to increasing CO 2. Proc Natl Acad Sci U S A 2018; 115:4093-4098. [PMID: 29610293 PMCID: PMC5910855 DOI: 10.1073/pnas.1720712115] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Predicting how increasing atmospheric CO2 will affect the hydrologic cycle is of utmost importance for a range of applications ranging from ecological services to human life and activities. A typical perspective is that hydrologic change is driven by precipitation and radiation changes due to climate change, and that the land surface will adjust. Using Earth system models with decoupled surface (vegetation physiology) and atmospheric (radiative) CO2 responses, we here show that the CO2 physiological response has a dominant role in evapotranspiration and evaporative fraction changes and has a major effect on long-term runoff compared with radiative or precipitation changes due to increased atmospheric CO2 This major effect is true for most hydrological stress variables over the largest fraction of the globe, except for soil moisture, which exhibits a more nonlinear response. This highlights the key role of vegetation in controlling future terrestrial hydrologic response and emphasizes that the carbon and water cycles are intimately coupled over land.
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Affiliation(s)
- Léo Lemordant
- Earth and Environmental Engineering Department, Columbia University, New York, NY 10027;
| | - Pierre Gentine
- Earth and Environmental Engineering Department, Columbia University, New York, NY 10027;
- Earth Institute, Columbia University, New York, NY 10025
| | - Abigail S Swann
- Department of Atmospheric Sciences, University of Washington, Seattle, WA 98105
- Department of Biology, University of Washington, Seattle, WA 98195
| | - Benjamin I Cook
- NASA Goddard Institute for Space Studies, New York, NY 10025
- Ocean and Climate Physics, Lamont-Doherty Earth Observatory, Palisades, NY 10964
| | - Jacob Scheff
- Department of Geography & Earth Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223
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49
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Gentine P, Alemohammad SH. Reconstructed Solar-Induced Fluorescence: A Machine Learning Vegetation Product Based on MODIS Surface Reflectance to Reproduce GOME-2 Solar-Induced Fluorescence. Geophys Res Lett 2018; 45:3136-3146. [PMID: 30034047 PMCID: PMC6049983 DOI: 10.1002/2017gl076294] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 03/09/2018] [Accepted: 03/13/2018] [Indexed: 05/19/2023]
Abstract
Solar-induced fluorescence (SIF) observations from space have resulted in major advancements in estimating gross primary productivity (GPP). However, current SIF observations remain spatially coarse, infrequent, and noisy. Here we develop a machine learning approach using surface reflectances from Moderate Resolution Imaging Spectroradiometer (MODIS) channels to reproduce SIF normalized by clear sky surface irradiance from the Global Ozone Monitoring Experiment-2 (GOME-2). The resulting product is a proxy for ecosystem photosynthetically active radiation absorbed by chlorophyll (fAPARCh). Multiplying this new product with a MODIS estimate of photosynthetically active radiation provides a new MODIS-only reconstruction of SIF called Reconstructed SIF (RSIF). RSIF exhibits much higher seasonal and interannual correlation than the original SIF when compared with eddy covariance estimates of GPP and two reference global GPP products, especially in dry and cold regions. RSIF also reproduces intense productivity regions such as the U.S. Corn Belt contrary to typical vegetation indices and similarly to SIF.
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Affiliation(s)
- P. Gentine
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
| | - S. H. Alemohammad
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
- Radiant.EarthWashingtonDCUSA
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50
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Guérin M, Martin‐Benito D, von Arx G, Andreu‐Hayles L, Griffin KL, Hamdan R, McDowell NG, Muscarella R, Pockman W, Gentine P. Interannual variations in needle and sapwood traits of Pinus edulis branches under an experimental drought. Ecol Evol 2018; 8:1655-1672. [PMID: 29435241 PMCID: PMC5792598 DOI: 10.1002/ece3.3743] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Revised: 10/05/2017] [Accepted: 11/20/2017] [Indexed: 01/02/2023] Open
Abstract
In the southwestern USA, recent large-scale die-offs of conifers raise the question of their resilience and mortality under droughts. To date, little is known about the interannual structural response to droughts. We hypothesized that piñon pines (Pinus edulis) respond to drought by reducing the drop of leaf water potential in branches from year to year through needle morphological adjustments. We tested our hypothesis using a 7-year experiment in central New Mexico with three watering treatments (irrigated, normal, and rain exclusion). We analyzed how variation in "evaporative structure" (needle length, stomatal diameter, stomatal density, stomatal conductance) responded to watering treatment and interannual climate variability. We further analyzed annual functional adjustments by comparing yearly addition of needle area (LA) with yearly addition of sapwood area (SA) and distance to tip (d), defining the yearly ratios SA:LA and SA:LA/d. Needle length (l) increased with increasing winter and monsoon water supply, and showed more interannual variability when the soil was drier. Stomatal density increased with dryness, while stomatal diameter was reduced. As a result, anatomical maximal stomatal conductance was relatively invariant across treatments. SA:LA and SA:LA/d showed significant differences across treatments and contrary to our expectation were lower with reduced water input. Within average precipitation ranges, the response of these ratios to soil moisture was similar across treatments. However, when extreme soil drought was combined with high VPD, needle length, SA:LA and SA:LA/d became highly nonlinear, emphasizing the existence of a response threshold of combined high VPD and dry soil conditions. In new branch tissues, the response of annual functional ratios to water stress was immediate (same year) and does not attempt to reduce the drop of water potential. We suggest that unfavorable evaporative structural response to drought is compensated by dynamic stomatal control to maximize photosynthesis rates.
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Affiliation(s)
- Marceau Guérin
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
| | - Dario Martin‐Benito
- Forest EcologyDepartment of Environmental SciencesSwiss Federal Institute of TechnologyETH ZurichZürichSwitzerland
- Forest Research Center (INIA‐CIFOR)MadridSpain
- Tree‐ring LaboratoryLamont‐Doherty Earth Observatory of Columbia UniversityPalisadesNYUSA
| | - Georg von Arx
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- Climatic Change and Climate ImpactsInstitute for Environmental SciencesGenevaSwitzerland
| | - Laia Andreu‐Hayles
- Tree‐ring LaboratoryLamont‐Doherty Earth Observatory of Columbia UniversityPalisadesNYUSA
| | - Kevin L. Griffin
- Department of Earth and Environmental SciencesLamont‐Doherty Earth Observatory of Columbia UniversityPalisadesNYUSA
| | | | - Nate G. McDowell
- Atmospheric Sciences and Global Change DivisionPacific Northwest National LaboratoryRichlandWAUSA
| | - Robert Muscarella
- Ecoinformatics & BiodiversityDepartment of BioscienceAarhus UniversityAarhusDenmark
| | - William Pockman
- Department of BiologyUniversity of New MexicoAlbuquerqueNMUSA
| | - Pierre Gentine
- Department of Earth and Environmental EngineeringEarth InstituteColumbia UniversityNew YorkNYUSA
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