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Park M, Johnson NC, Delworth TL. The driving of North American climate extremes by North Pacific stationary-transient wave interference. Nat Commun 2024; 15:7318. [PMID: 39183212 PMCID: PMC11345455 DOI: 10.1038/s41467-024-51601-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 08/13/2024] [Indexed: 08/27/2024] Open
Abstract
Wave interference between transient waves and climatological stationary waves is a useful framework for diagnosing the magnitude of stationary waves. Here, we find that the wave interference over the North Pacific Ocean is an important driver of North American wintertime cold and heavy precipitation extremes in the present climate, but that this relationship is projected to weaken under increasing greenhouse gas emissions. When daily circulation anomalies are in-phase with the climatological mean state, the anomalous transport of heat and moisture causes the enhanced occurrence of cold extremes across the continental U.S. and a significant decrease of heavy precipitation extremes in the western U.S. In a future emissions scenario, the climatological stationary wave over the eastern North Pacific weakens and shifts spatially, which alters and generally weakens the relationship between wave interference and North American climate extremes. Our results underscore that the prediction of changes in regional wave interference is pivotal for understanding the future regional climate variability.
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Affiliation(s)
- Mingyu Park
- Program in Atmospheric and Oceanic Sciences, Princeton University, Princeton, NJ, USA.
- Geophysical Fluid Dynamics Laboratory, National Oceanic and Atmospheric Administration, Princeton, NJ, USA.
| | - Nathaniel C Johnson
- Geophysical Fluid Dynamics Laboratory, National Oceanic and Atmospheric Administration, Princeton, NJ, USA
| | - Thomas L Delworth
- Geophysical Fluid Dynamics Laboratory, National Oceanic and Atmospheric Administration, Princeton, NJ, USA
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2
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D’Olivo JP, Zinke J, Goyal R, England MH, Purich A, Corrège T, Zorita E, Scholz D, Weber M, Carriquiry JD. Coral Sr/Ca-SST reconstruction from Fiji extending to ~1370 CE reveals insights into the Interdecadal Pacific Oscillation. SCIENCE ADVANCES 2024; 10:eado5107. [PMID: 39141738 PMCID: PMC11323954 DOI: 10.1126/sciadv.ado5107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 07/10/2024] [Indexed: 08/16/2024]
Abstract
The southwestern tropical Pacific is a key center for the Interdecadal Pacific Oscillation (IPO), which regulates global climate. This study introduces a groundbreaking 627-year coral Sr/Ca sea surface temperature reconstruction from Fiji, representing the IPO's southwestern pole. Merging this record with other Fiji and central tropical Pacific records, we reconstruct the SST gradient between the southwestern and central Pacific (SWCP), providing a reliable proxy for IPO variability from 1370 to 1997. This reconstruction reveals distinct centennial-scale temperature trends and insights into Pacific-wide climate impacts and teleconnections. Notably, the 20th century conditions, marked by simultaneous basin-scale warming and weak tropical Pacific zonal-meridional gradients, deviate from trends observed during the past six centuries. Combined with model simulations, our findings reveal that a weak SWCP gradient most markedly affects IPO-related rainfall patterns in the equatorial Pacific. Persistent synchronous western and central Pacific warming rates could lead to further drying climate across the Coral Sea region, adversely affecting Pacific Island nations.
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Affiliation(s)
- Juan P. D’Olivo
- Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos 77580, Mexico
- Institute for Geosciences, Freie Universität Berlin, Berlin 12249, Germany
- Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, 22860 Ensenada, Baja California, Mexico
| | - Jens Zinke
- School of Geology, Geography and Environment, University of Leicester, Leicester LE17RH, UK
- Molecular and Life Sciences, Curtin University, Perth, WA 6102, Australia
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
| | - Rishav Goyal
- Climate Change Research Centre, University of New South Wales, Sydney, NSW 2052, Australia
- ARC Centre for Excellence in Antarctic Science (ACEAS), University of New South Wales, Sydney, NSW 2052, Australia
| | - Matthew H. England
- ARC Centre for Excellence in Antarctic Science (ACEAS), University of New South Wales, Sydney, NSW 2052, Australia
- Centre for Marine Science and Innovation, University of New South Wales, Sydney, NSW 2052, Australia
| | - Ariaan Purich
- School of Earth, Atmosphere and Environment, and ARC Special Research Initiative for Securing Antarctica’s Environmental Future, Monash University, Melbourne, VIC 3800, Australia
| | - Thierry Corrège
- EPOC, UMR 5805 CNR5, Université de Bordeaux, Pessac CEDEX F-33615, France
| | - Eduardo Zorita
- Institute of Coastal Systems–Analysis and Modeling, Helmholtz Centre Hereon, Geesthacht 21502, Germany
| | - Denis Scholz
- Institut für Geowissenschaften, Johannes Gutenberg-Universität Mainz, Mainz D-55128 Germany
| | - Michael Weber
- Institut für Geowissenschaften, Johannes Gutenberg-Universität Mainz, Mainz D-55128 Germany
| | - José D. Carriquiry
- Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, 22860 Ensenada, Baja California, Mexico
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3
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Kamil NN, Xiao S, Syed Salleh SN, Xu H, Zhuang CC. Nonlinear impacts of climate anomalies on oil palm productivity. Heliyon 2024; 10:e35798. [PMID: 39170218 PMCID: PMC11337023 DOI: 10.1016/j.heliyon.2024.e35798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 06/18/2024] [Accepted: 08/04/2024] [Indexed: 08/23/2024] Open
Abstract
Oil palm contributes to various global needs as one of the most productive oil crops, but there exist ongoing concerns regarding its yield reductions and associated environmental impacts resulting from land conversion. This is the first detailed report investigating the nonlinear threats to estate-level oil palm yields posed by El Niño Southern Oscillation (ENSO) in the equatorial Pacific Ocean, a major driver of climate variability. Using the Malaysian Palm Oil Board administrative records on monthly performances reported by oil palm estates through the e-submissions portal spanning from January 2015 to June 2023, we focused on elucidating the impacts of ENSO on fresh fruit bunch yield, oil extraction rate, and oil yield. We found that both El Niño and La Niña conditions, characterized by extreme levels of ENSO indices cumulated over lags of 0-23 months prior to harvest, were associated with statistically significant reductions in yields. Lag association patterns unveiled that production risks were linked to pre-harvest exposure to extreme ENSO indices in various time windows. Subgroup analyses further revealed that the effects were pronounced in labor-intensive estates and those lacking fertilizer investments. This study underscores the necessity for adaptation strategies in response to future climate anomalies.
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Affiliation(s)
- Nur Nadia Kamil
- Economics and Industry Development Division, Malaysian Palm Oil Board, Selangor, Malaysia
| | - Saizi Xiao
- School of Economics, University of Nottingham Malaysia, Selangor, Malaysia
| | - Sharifah Nabilah Syed Salleh
- Department of Economics, Kulliyyah of Economics and Management Sciences, International Islamic University Malaysia, Kuala Lumpur, Malaysia
| | - Hongbing Xu
- Department of Occupational and Environmental Health, Peking University School of Public Health, Beijing, China
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4
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Xu H, Zhuang CC, Oddo VM, Malembaka EB, He X, Zhang Q, Huang W. Maternal preconceptional and prenatal exposure to El Niño Southern Oscillation levels and child mortality: a multi-country study. Nat Commun 2024; 15:6034. [PMID: 39019882 PMCID: PMC11254917 DOI: 10.1038/s41467-024-50467-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 07/05/2024] [Indexed: 07/19/2024] Open
Abstract
El Niño Southern Oscillation (ENSO) has been shown to relate to the epidemiology of childhood infectious diseases, but evidence for whether they increase child deaths is limited. Here, we investigate the impact of mothers' ENSO exposure during and prior to delivery on child mortality by constructing a retrospective cohort study in 38 low- and middle-income countries. We find that high levels of ENSO indices cumulated over 0-12 lagged months before delivery are associated with significant increases in risks of under-five mortality; with the hazard ratio ranging from 1.33 (95% confidence interval [CI], 1.26, 1.40) to 1.89 (95% CI, 1.78, 2.00). Child mortality risks are particularly related to maternal exposure to El Niño-like conditions in the 0th-1st and 6th-12th lagged months. The El Niño effects are larger in rural populations and those with unsafe sources of drinking water and less education. Thus, preventive interventions are particularly warranted for the socio-economically disadvantaged.
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Affiliation(s)
- Hongbing Xu
- Department of Occupational and Environmental Health, Peking University School of Public Health, Beijing, China
- Peking University Institute of Environmental Medicine, Beijing, China
| | | | - Vanessa M Oddo
- Department of Kinesiology and Nutrition, College of Applied Health Sciences, University of Illinois Chicago, Chicago, IL, USA
| | - Espoir Bwenge Malembaka
- Center for Tropical Diseases and Global Health, Université Catholique de Bukavu, Bukavu, Democratic Republic of the Congo
- Faculty of Medicine, Université Catholique de Bukavu, Bukavu, Democratic Republic of the Congo
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Xinghou He
- Department of Occupational and Environmental Health, Peking University School of Public Health, Beijing, China
- Peking University Institute of Environmental Medicine, Beijing, China
| | - Qinghong Zhang
- Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, China
| | - Wei Huang
- Department of Occupational and Environmental Health, Peking University School of Public Health, Beijing, China
- Peking University Institute of Environmental Medicine, Beijing, China
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5
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Guilderson TP, Glynn DS, McCarthy MD. Tropical decadal variability in nutrient supply and phytoplankton community in the Central Equatorial Pacific during the late Holocene. Sci Rep 2024; 14:4161. [PMID: 38378879 PMCID: PMC10879156 DOI: 10.1038/s41598-024-54635-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 02/14/2024] [Indexed: 02/22/2024] Open
Abstract
We have reconstructed baseline δ15N and δ13C of export production at Kingman Reef in the Central Equatorial Pacific (CEP) at sub-decadal resolution, nearly continuously over the last 2000 years. The changes in δ15N reflects the strength of the North Equatorial Counter Current (NECC) relative to the South Equatorial Current (SEC), and to a lesser extent, the North Equatorial Current (NEC). Seasonal to multi-decadal variation in the strength of these currents, through the redistribution of heat, have global climate impacts and influence marine and terrestrial ecosystems. We use modern El Niño-La Nina dynamics and the Tropical Pacific Decadal Variability (TPDV) pattern, which is defined in the CEP, as a framework for analyzing the isotopic data. The CEP δ15N and δ13C records exhibit multi-decadal (50-60 year) variability consistent with TPDV. A large multi-centennial feature in the CEP δ15N data, within age-model uncertainties, is consistent with one of the prolonged dry-pluvial sequences in the American west at the end of the Medieval Climate Anomaly, where low TPDV is correlated with drier conditions. This unique record shows that the strength of the NECC, as reflected in baseline δ15N and δ13C, has at quasi-predictable intervals throughout the late Holocene, toggled the phytoplankton community between prokaryotes and picoplankton versus eukaryotes.
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Affiliation(s)
- T P Guilderson
- Ocean Sciences Department, University of California - Santa Cruz, 1156 High Street, Santa Cruz, CA, USA.
| | - D S Glynn
- Ocean Sciences Department, University of California - Santa Cruz, 1156 High Street, Santa Cruz, CA, USA
| | - M D McCarthy
- Ocean Sciences Department, University of California - Santa Cruz, 1156 High Street, Santa Cruz, CA, USA
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6
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Guo T, Wei J, Li X, Yu J. Environmental context of phenotypic plasticity in flowering time in sorghum and rice. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1004-1015. [PMID: 37819624 PMCID: PMC10837014 DOI: 10.1093/jxb/erad398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 10/17/2023] [Indexed: 10/13/2023]
Abstract
Phenotypic plasticity is an important topic in biology and evolution. However, how to generate broadly applicable insights from individual studies remains a challenge. Here, with flowering time observed from a large geographical region for sorghum and rice genetic populations, we examine the consistency of parameter estimation for reaction norms of genotypes across different subsets of environments and searched for potential strategies to inform the study design. Both sample size and environmental mean range of the subset affected the consistency. The subset with either a large range of environmental mean or a large sample size resulted in genetic parameters consistent with the overall pattern. Furthermore, high accuracy through genomic prediction was obtained for reaction norm parameters of untested genotypes using models built from tested genotypes under the subsets of environments with either a large range or a large sample size. With 1428 and 1674 simulated settings, our analyses suggested that the distribution of environmental index values of a site should be considered in designing experiments. Overall, we showed that environmental context was critical, and considerations should be given to better cover the intended range of the environmental variable. Our findings have implications for the genetic architecture of complex traits, plant-environment interaction, and climate adaptation.
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Affiliation(s)
- Tingting Guo
- Hubei Hongshan Laboratory, Wuhan, Hubei, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jialu Wei
- Department of Agronomy, Iowa State University, Ames, IA, USA
| | - Xianran Li
- USDA, Agricultural Research Service, Wheat Health, Genetics, and Quality Research Unit, Pullman, WA, USA
| | - Jianming Yu
- Department of Agronomy, Iowa State University, Ames, IA, USA
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7
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Hwang YT, Xie SP, Chen PJ, Tseng HY, Deser C. Contribution of anthropogenic aerosols to persistent La Niña-like conditions in the early 21st century. Proc Natl Acad Sci U S A 2024; 121:e2315124121. [PMID: 38252827 PMCID: PMC10835045 DOI: 10.1073/pnas.2315124121] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 12/08/2023] [Indexed: 01/24/2024] Open
Abstract
The discrepancy between the observed lack of surface warming in the eastern equatorial Pacific and climate model projections of an El Niño-like warming pattern confronts the climate research community. While anthropogenic aerosols have been suggested as a cause, the prolonged cooling trend over the equatorial Pacific appears in conflict with Northern Hemisphere aerosol emission reduction since the 1980s. Here, using CESM, we show that the superposition of fast and slow responses to aerosol emission change-an increase followed by a decrease-can sustain the La Niña-like condition for a longer time than expected. The rapid adjustment of Hadley Cell to aerosol reduction triggers joint feedback between low clouds, wind, evaporation, and sea surface temperature in the Southeast Pacific, leading to a wedge-shaped cooling that extends to the central equatorial Pacific. Meanwhile, the northern subtropical cell gradually intensifies, resulting in equatorial subsurface cooling that lasts for decades.
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Affiliation(s)
- Yen-Ting Hwang
- Department of Atmospheric Sciences, National Taiwan University, Taipei 10617, Taiwan
| | - Shang-Ping Xie
- Scripps Institute of Oceanography, University of California San Diego, La Jolla, CA 92093
| | - Po-Ju Chen
- Department of Atmospheric Sciences, National Taiwan University, Taipei 10617, Taiwan
- Department of Atmospheric, Oceanic, and Earth Sciences, George Mason University, Fairfax, VA 22030
| | - Hung-Yi Tseng
- Department of Atmospheric Sciences, National Taiwan University, Taipei 10617, Taiwan
| | - Clara Deser
- Climate and Global Dynamics Division, National Center for Atmospheric Research, Boulder, CO 80305
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8
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Falster G, Konecky B, Coats S, Stevenson S. Forced changes in the Pacific Walker circulation over the past millennium. Nature 2023; 622:93-100. [PMID: 37612511 PMCID: PMC10550830 DOI: 10.1038/s41586-023-06447-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 07/14/2023] [Indexed: 08/25/2023]
Abstract
The Pacific Walker circulation (PWC) has an outsized influence on weather and climate worldwide. Yet the PWC response to external forcings is unclear1,2, with empirical data and model simulations often disagreeing on the magnitude and sign of these responses3. Most climate models predict that the PWC will ultimately weaken in response to global warming4. However, the PWC strengthened from 1992 to 2011, suggesting a significant role for anthropogenic and/or volcanic aerosol forcing5, or internal variability. Here we use a new annually resolved, multi-method, palaeoproxy-derived PWC reconstruction ensemble (1200-2000) to show that the 1992-2011 PWC strengthening is anomalous but not unprecedented in the context of the past 800 years. The 1992-2011 PWC strengthening was unlikely to have been a consequence of volcanic forcing and may therefore have resulted from anthropogenic aerosol forcing or natural variability. We find no significant industrial-era (1850-2000) PWC trend, contrasting the PWC weakening simulated by most climate models3. However, an industrial-era shift to lower-frequency variability suggests a subtle anthropogenic influence. The reconstruction also suggests that volcanic eruptions trigger El Niño-like PWC weakening, similar to the response simulated by climate models.
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Affiliation(s)
- Georgina Falster
- Australian Research Council Centre of Excellence for Climate Extremes, Canberra, Australian Capital Territory, Australia.
- Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, USA.
- Research School of Earth Sciences, Australian National University, Canberra, Australia.
| | - Bronwen Konecky
- Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Sloan Coats
- Department of Earth Sciences, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Samantha Stevenson
- Bren School of Environmental Science and Management, University of California, Santa Barbara, Santa Barbara, CA, USA
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9
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Hodapp D, Roca IT, Fiorentino D, Garilao C, Kaschner K, Kesner-Reyes K, Schneider B, Segschneider J, Kocsis ÁT, Kiessling W, Brey T, Froese R. Climate change disrupts core habitats of marine species. GLOBAL CHANGE BIOLOGY 2023; 29:3304-3317. [PMID: 36789726 DOI: 10.1111/gcb.16612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 12/20/2022] [Indexed: 05/16/2023]
Abstract
Driven by climate change, marine biodiversity is undergoing a phase of rapid change that has proven to be even faster than changes observed in terrestrial ecosystems. Understanding how these changes in species composition will affect future marine life is crucial for conservation management, especially due to increasing demands for marine natural resources. Here, we analyse predictions of a multiparameter habitat suitability model covering the global projected ranges of >33,500 marine species from climate model projections under three CO2 emission scenarios (RCP2.6, RCP4.5, RCP8.5) up to the year 2100. Our results show that the core habitat area will decline for many species, resulting in a net loss of 50% of the core habitat area for almost half of all marine species in 2100 under the high-emission scenario RCP8.5. As an additional consequence of the continuing distributional reorganization of marine life, gaps around the equator will appear for 8% (RCP2.6), 24% (RCP4.5), and 88% (RCP8.5) of marine species with cross-equatorial ranges. For many more species, continuous distributional ranges will be disrupted, thus reducing effective population size. In addition, high invasion rates in higher latitudes and polar regions will lead to substantial changes in the ecosystem and food web structure, particularly regarding the introduction of new predators. Overall, our study highlights that the degree of spatial and structural reorganization of marine life with ensued consequences for ecosystem functionality and conservation efforts will critically depend on the realized greenhouse gas emission pathway.
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Affiliation(s)
- Dorothee Hodapp
- Helmholtz-Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Oldenburg, Germany
- Alfred-Wegener-Institute, Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Irene T Roca
- Helmholtz-Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Oldenburg, Germany
- Alfred-Wegener-Institute, Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
- Laboratoire interdisciplinaire de simulation socio-écologique (LISSÉ), Université de Québec en Outaouais (UQO), Gatineau, Canada
| | - Dario Fiorentino
- Helmholtz-Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Oldenburg, Germany
- Alfred-Wegener-Institute, Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
- Thünen Institute of Sea Fisheries, Bremerhaven, Germany
| | | | - Kristin Kaschner
- Department of Biometry and Environmental Systems Analysis, Albert-Ludwigs University, Freiburg im Breisgau, Germany
| | | | - Birgit Schneider
- Institute of Geosciences, Christian-Albrechts University of Kiel, Kiel, Germany
| | | | - Ádám T Kocsis
- GeoZentrum Nordbayern, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Wolfgang Kiessling
- GeoZentrum Nordbayern, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Thomas Brey
- Helmholtz-Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Oldenburg, Germany
- Alfred-Wegener-Institute, Helmholtz-Centre for Polar and Marine Research, Bremerhaven, Germany
- University of Bremen, Bremen, Germany
| | - Rainer Froese
- GEOMAR Helmholtz-Centre for Ocean Research, Kiel, Germany
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10
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Wu X, Yeager SG, Deser C, Rosenbloom N, Meehl GA. Volcanic forcing degrades multiyear-to-decadal prediction skill in the tropical Pacific. SCIENCE ADVANCES 2023; 9:eadd9364. [PMID: 37043583 PMCID: PMC10096591 DOI: 10.1126/sciadv.add9364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 03/15/2023] [Indexed: 06/19/2023]
Abstract
Volcanic aerosol forcing can affect global climate, but its role in climate prediction remains poorly understood. We isolate the impact of volcanic eruptions on multiyear-to-decadal climate prediction skill by comparing two suites of initialized decadal hindcasts conducted with and without historical volcanic forcing. Unexpectedly, the inclusion of volcanic forcing in the prediction system significantly degrades the forecast skill of detrended multiyear-to-decadal sea surface temperature (SST) variability in the central-eastern tropical Pacific. The ensemble mean hindcasts produce multiyear-to-decadal tropical Pacific SST cooling in response to large tropical volcanic eruptions through thermodynamic and El Niño-Southern Oscillation (ENSO)-like dynamic processes. However, in observations, these eruptions coincided with tropical Pacific warming, which is well predicted by the no-volcano hindcasts and, hence, is likely related to internal climate variability. Improved model representation of volcanic response and its interaction with internal climate variability is required to advance prediction of tropical Pacific decadal variability and associated global impacts.
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11
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Wu CH, Lee SY, Tsai IC, Shiu CJ, Chen YY. Volcanic contribution to the 1990s North Pacific climate shift in winter. Sci Rep 2023; 13:5672. [PMID: 37024550 PMCID: PMC10079832 DOI: 10.1038/s41598-023-32956-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 04/05/2023] [Indexed: 04/08/2023] Open
Abstract
It is debatable whether external forcing can change the state of the climate. By investigating decadal changes with and without including the 1990s stratospheric volcanic aerosols, we explored the volcanic eruptions contribution to decadal climate regime shifts occurring in boreal winter over the North Pacific. The volcanic eruptions contribution can be characterized as a series of rapid changes, including the strengthening and poleward shift of the midlatitude westerly jet stream. In addition to the short-lived radiative effects primarily induced by the 1991 Mount Pinatubo eruption, the volcanically driven decadal change can be observed in the mid-to-late 1990s, suggesting a time-lagged characteristic of the volcanic climate impact. Compared with the decadal change irrelevant to volcanic eruption, the decadal state more dramatically enters into the next phase when volcanic forcing is included. The climate oscillation-related pattern shifts that occurred across the 1990s can provide insights into volcanically induced changes in decadal atmospheric circulation.
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Affiliation(s)
- Chi-Hua Wu
- Research Center for Environmental Changes, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan.
| | - Shih-Yu Lee
- Research Center for Environmental Changes, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan
| | - I-Chun Tsai
- Research Center for Environmental Changes, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan
| | - Chein-Jung Shiu
- Research Center for Environmental Changes, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan
| | - Yi-Ying Chen
- Research Center for Environmental Changes, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan
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12
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Di Lorenzo E, Xu T, Zhao Y, Newman M, Capotondi A, Stevenson S, Amaya DJ, Anderson BT, Ding R, Furtado JC, Joh Y, Liguori G, Lou J, Miller AJ, Navarra G, Schneider N, Vimont DJ, Wu S, Zhang H. Modes and Mechanisms of Pacific Decadal-Scale Variability. ANNUAL REVIEW OF MARINE SCIENCE 2023; 15:249-275. [PMID: 36112981 DOI: 10.1146/annurev-marine-040422-084555] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The modes of Pacific decadal-scale variability (PDV), traditionally defined as statistical patterns of variance, reflect to first order the ocean's integration (i.e., reddening) of atmospheric forcing that arises from both a shift and a change in strength of the climatological (time-mean) atmospheric circulation. While these patterns concisely describe PDV, they do not distinguish among the key dynamical processes driving the evolution of PDV anomalies, including atmospheric and ocean teleconnections and coupled feedbacks with similar spatial structures that operate on different timescales. In this review, we synthesize past analysis using an empirical dynamical model constructed from monthly ocean surface anomalies drawn from several reanalysis products, showing that the PDV modes of variance result from two fundamental low-frequency dynamical eigenmodes: the North Pacific-central Pacific (NP-CP) and Kuroshio-Oyashio Extension (KOE) modes. Both eigenmodes highlight how two-way tropical-extratropical teleconnection dynamics are the primary mechanisms energizing and synchronizing the basin-scale footprint of PDV. While the NP-CP mode captures interannual- to decadal-scale variability, the KOE mode is linked to the basin-scale expression of PDV on decadal to multidecadal timescales, including contributions from the South Pacific.
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Affiliation(s)
- E Di Lorenzo
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, Rhode Island, USA;
| | - T Xu
- Physical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado, USA
| | - Y Zhao
- Deep-Sea Multidisciplinary Research Center, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China
| | - M Newman
- Physical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado, USA
- Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, Boulder, Colorado, USA
| | - A Capotondi
- Physical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado, USA
- Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, Boulder, Colorado, USA
| | - S Stevenson
- Bren School of Environmental Science and Management, University of California, Santa Barbara, California, USA
| | - D J Amaya
- Physical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado, USA
| | - B T Anderson
- Department of Earth and Environment, Boston University, Boston, Massachusetts, USA
| | - R Ding
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China
| | - J C Furtado
- School of Meteorology, University of Oklahoma, Norman, Oklahoma, USA
| | - Y Joh
- Atmospheric and Oceanic Sciences Program, Princeton University, Princeton, New Jersey, USA
| | - G Liguori
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
- School of Earth, Atmosphere, and Environment, Monash University, Melbourne, Victoria, Australia
| | - J Lou
- Physical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado, USA
- Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, Boulder, Colorado, USA
| | - A J Miller
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California, USA
| | - G Navarra
- Program in Ocean Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - N Schneider
- International Pacific Research Center and Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, Hawaii, USA
| | - D J Vimont
- Department of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - S Wu
- Laboratory for Climate and Ocean-Atmosphere Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, China
| | - H Zhang
- Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas, USA
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13
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Xu H, Zhuang CC, Guan X, He X, Wang T, Wu R, Zhang Q, Huang W. Associations of climate variability driven by El Niño-southern oscillation with excess mortality and related medical costs in Chinese elderly. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158196. [PMID: 35995158 DOI: 10.1016/j.scitotenv.2022.158196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/15/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
Climate variability driven by El Niño-Southern Oscillation (ENSO) is a significant public health concern in parallel with global population aging; however, its role in healthy aging is less studied. We examined the longitudinal impacts of ENSO exposure on excess mortality and related medical costs in the elderly from 23 provinces of China. A total of 27,533 non-accidental all-cause deaths were recorded in 30,763 participants during 1998-2018. We found that both low and high levels of ENSO metrics over lags of 0-12 months were associated with increased mortality risks. Specifically, comparing the 10th percentile (-1.8) and 90th percentile (2.0) multivariate El Niño index (MEI) levels to the reference level with the minimum effect of MEI exposure, the risk of mortality was 1.87 (95 % confidence interval [CI], 1.75, 2.00) and 4.89 (95 % CI, 4.36, 5.49), respectively. ENSO exposure was also positively related to medical costs. Further, the associations were stronger among drinkers, lower-income participants, and those with higher blood pressure and heart rate measured at the most recent follow-ups. Our results suggested that ENSO exposure was capable of heightening mortality risks and medical burden among older elderly adults, highlighting that climate variability driven by ENSO could be a crucial determinant of healthy aging.
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Affiliation(s)
- Hongbing Xu
- Department of Occupational and Environmental Health, Peking University School of Public Health, Peking University Institute of Environmental Medicine, Beijing 100191, China
| | - Castiel Chen Zhuang
- Peking University School of Economics, Beijing 100871, China; Department of Economics, University of Washington, Seattle, WA 98195, USA.
| | - Xinpeng Guan
- Department of Occupational and Environmental Health, Peking University School of Public Health, Peking University Institute of Environmental Medicine, Beijing 100191, China
| | - Xinghou He
- Department of Occupational and Environmental Health, Peking University School of Public Health, Peking University Institute of Environmental Medicine, Beijing 100191, China
| | - Tong Wang
- Department of Occupational and Environmental Health, Peking University School of Public Health, Peking University Institute of Environmental Medicine, Beijing 100191, China
| | - Rongshan Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, State Environmental Protection Key Laboratory of Ecological Effect and Risk Assessment of Chemicals, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Qinghong Zhang
- Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China
| | - Wei Huang
- Department of Occupational and Environmental Health, Peking University School of Public Health, Peking University Institute of Environmental Medicine, Beijing 100191, China
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14
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Xu T, Newman M, Capotondi A, Stevenson S, Di Lorenzo E, Alexander MA. An increase in marine heatwaves without significant changes in surface ocean temperature variability. Nat Commun 2022; 13:7396. [PMID: 36456576 PMCID: PMC9715661 DOI: 10.1038/s41467-022-34934-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 11/11/2022] [Indexed: 12/03/2022] Open
Abstract
Marine heatwaves (MHWs)-extremely warm, persistent sea surface temperature (SST) anomalies causing substantial ecological and economic consequences-have increased worldwide in recent decades. Concurrent increases in global temperatures suggest that climate change impacted MHW occurrences, beyond random changes arising from natural internal variability. Moreover, the long-term SST warming trend was not constant but instead had more rapid warming in recent decades. Here we show that this nonlinear trend can-on its own-appear to increase SST variance and hence MHW frequency. Using a Linear Inverse Model to separate climate change contributions to SST means and internal variability, both in observations and CMIP6 historical simulations, we find that most MHW increases resulted from regional mean climate trends that alone increased the probability of SSTs exceeding a MHW threshold. Our results suggest the need to carefully attribute global warming-induced changes in climate extremes, which may not always reflect underlying changes in variability.
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Affiliation(s)
- Tongtong Xu
- NOAA Physical Sciences Laboratory, Boulder, CO, USA.
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.
| | - Matthew Newman
- NOAA Physical Sciences Laboratory, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Antonietta Capotondi
- NOAA Physical Sciences Laboratory, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Samantha Stevenson
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA, USA
| | - Emanuele Di Lorenzo
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI, USA
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15
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Zhang M, Shu Q, Zhao C, Wang G, Zhang Y, Xue Y, Song Z, Wu Z, Qiao F. Spatiotemporal propagating decadal signal of ocean heat content and thermocline depth identified in the tropical Pacific. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:155972. [PMID: 35588812 DOI: 10.1016/j.scitotenv.2022.155972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 05/04/2022] [Accepted: 05/11/2022] [Indexed: 06/15/2023]
Abstract
Tropical Pacific decadal variability (TPDV) and its mechanisms are essential for understanding long-term variations in global climate. The spatiotemporal pattern of this decadal variation has yet to be clarified. Here, on the basis of observational data with the help of the adaptive data analysis method, we extracted and investigated the spatiotemporal evolution of the tropical Pacific decadal variability in upper ocean heat content (UOHC) and thermocline depth. The tropical decadal signal propagated eastward along the equator from the western Pacific to the eastern Pacific after the 1970s, with a speed of 4-5 cm s-1 yielding a decadal oscillation of approximately 11-13 years. This decadal variability of the thermocline fluctuations (UOHC) was proven to be closely correlated with western wind anomalies since the 1970s and may have been induced by the regime shift of the Pacific decadal oscillation. These peaks of decadal signals corresponded well with the strong El Niño-Southern Oscillation (ENSO) events, reflecting nonlinear rectification of ENSOs on TPDV. Moreover, the TPDV showed a modulating signal on moderate and weak ENSO events.
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Affiliation(s)
- Min Zhang
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Shandong Key Laboratory of Marine Sciences and Numerical Modeling, Qingdao, China
| | - Qi Shu
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Shandong Key Laboratory of Marine Sciences and Numerical Modeling, Qingdao, China
| | - Chang Zhao
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Shandong Key Laboratory of Marine Sciences and Numerical Modeling, Qingdao, China
| | - Gang Wang
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Shandong Key Laboratory of Marine Sciences and Numerical Modeling, Qingdao, China
| | - Yuanling Zhang
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Shandong Key Laboratory of Marine Sciences and Numerical Modeling, Qingdao, China
| | - Yuhuan Xue
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Shandong Key Laboratory of Marine Sciences and Numerical Modeling, Qingdao, China
| | - Zhenya Song
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Shandong Key Laboratory of Marine Sciences and Numerical Modeling, Qingdao, China
| | - Zhaohua Wu
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Department of Earth, Ocean, and Atmospheric Science, Center for Ocean-Atmospheric Prediction Studies, Florida State University, USA
| | - Fangli Qiao
- First Institute of Oceanography, Key Laboratory of Marine Sciences and Numerical Modeling, Ministry of Natural Resources, Qingdao, China; Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; Shandong Key Laboratory of Marine Sciences and Numerical Modeling, Qingdao, China.
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16
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Shields CA, Wille JD, Marquardt Collow AB, Maclennan M, Gorodetskaya IV. Evaluating Uncertainty and Modes of Variability for Antarctic Atmospheric Rivers. GEOPHYSICAL RESEARCH LETTERS 2022; 49:e2022GL099577. [PMID: 36249465 PMCID: PMC9541479 DOI: 10.1029/2022gl099577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/04/2022] [Accepted: 08/11/2022] [Indexed: 06/16/2023]
Abstract
Antarctic atmospheric rivers (ARs) are driven by their synoptic environments and lead to profound and varying impacts along the coastlines and over the continent. The definition and detection of ARs over Antarctica accounts for large uncertainty in AR metrics, and consequently, impacts quantification. We find that Antarctic-specific detection tools consistently capture the AR footprint inland over ice sheets, whereas most global detection tools do not. Large-scale synoptic environments and associated ARs, however, are broadly consistent across detection tools. Using data from the Atmospheric River Tracking Method Intercomparison Project and global reanalyses, we quantify the uncertainty in Antarctic AR metrics and evaluate large-scale environments in the context of decadal and interannual modes of variability. The Antarctic western hemisphere has stronger connections to both decadal and interannual modes of variability compared to East Antarctica, and the Indian Ocean Dipole's influence on Antarctic ARs is stronger while in phase with El Nino Southern Oscillation.
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Affiliation(s)
- Christine A. Shields
- Climate and Global Dynamics LaboratoryNational Center for Atmospheric ResearchBoulderCOUSA
| | - Jonathan D. Wille
- Institut des Géosciences de l'EnvironnementCNRS/UGA/IRD/G‐INPSaint Martin d'HèresFrance
| | - Allison B. Marquardt Collow
- University of Maryland Baltimore CountyBaltimoreMDUSA
- Global Modeling and Assimilation OfficeNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Michelle Maclennan
- Department of Atmospheric and Oceanic ScienceUniversity of Colorado BoulderBoulderCOUSA
| | - Irina V. Gorodetskaya
- Department of PhysicsCESAM—Centre for Environmental and Marine StudiesUniversity of AveiroAveiroPortugal
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17
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Worsening drought of Nile basin under shift in atmospheric circulation, stronger ENSO and Indian Ocean dipole. Sci Rep 2022; 12:8049. [PMID: 35577921 PMCID: PMC9110430 DOI: 10.1038/s41598-022-12008-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 04/11/2022] [Indexed: 11/26/2022] Open
Abstract
Until now, driving mechanisms behind recurring droughts and hydroclimate variations that controls the Nile River Basin (NRB) remains poorly understood. Our results show significant hydroclimatic changes that contributed to recent increasing aridity of NRB since the 1970s. Besides climate warming, the influence of stronger ENSO and Indian Ocean dipole (IOD) in NRB has increased after 1980s, which have significantly contributed to NRB’s drought severity at inter-annual to inter-decadal timescales. Our results demonstrate that warming, El Niño and IOD have played a crucial role on NRB’s inter-decadal hydroclimate variability, but IOD has played a more important role in modulating NRB’s hydroclimate at higher timescales than El Niño. Results also indicate that the impacts of positive phases of ENSO and IOD events are larger than the negative phases in the NRB hydroclimate. Further, the southward (westward) shift in stream functions and meridional (zonal) winds caused an enhancement in the blocking pattern, with strong anticyclonic waves of dry air that keeps moving into NRB, has resulted in drier NRB, given stream function, geopotential height and U-wind anomalies associated with El Niño shows that changes in regional atmospheric circulations during more persistent and stronger El Niño has resulted in drier NRB. After 1970s, El Niño, IOD, and drought indices shows significant anti-phase relationships, which again demonstrates that more frequent and severe El Niño and IOD in recent years has led to more severe droughts in NRB. Our results also demonstrate that IOD and and the western pole of the Indian Ocean Dipole (WIO) are better predictors of the Nile flow than El Niño, where its flow has decreased by 13.7 (upstream) and by 114.1 m3/s/decade (downstream) after 1964. In summary, under the combined impact of warming and stronger IOD and El Niño, future droughts of the NRB will worsen.
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18
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Twenty-first century hydroclimate: A continually changing baseline, with more frequent extremes. Proc Natl Acad Sci U S A 2022; 119:e2108124119. [PMID: 35286205 PMCID: PMC8944869 DOI: 10.1073/pnas.2108124119] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Twenty-first century trends in hydroclimate are so large that future average conditions will, in most cases, fall into the range of what we would today consider extreme drought or pluvial states. Using large climate model ensembles, we remove the background trend and find that the risk of droughts and pluvials relative to that (changing) baseline is fairly similar to the 20th century risk. By continually adapting to long-term background changes, these risks could therefore perhaps be minimized. However, increases in the frequency of extremely wet and dry years are still present even after removing the trend, indicating that sustainably managing hydroclimate-driven risks in a warmer world will face increasingly difficult challenges. Variability in hydroclimate impacts natural and human systems worldwide. In particular, both decadal variability and extreme precipitation events have substantial effects and are anticipated to be strongly influenced by climate change. From a practical perspective, these impacts will be felt relative to the continuously evolving background climate. Removing the underlying forced trend is therefore necessary to assess the relative impacts, but to date, the small size of most climate model ensembles has made it difficult to do this. Here we use an archive of large ensembles run under a high-emissions scenario to determine how decadal “megadrought” and “megapluvial” events—and shorter-term precipitation extremes—will vary relative to that changing baseline. When the trend is retained, mean state changes dominate: In fact, soil moisture changes are so large in some regions that conditions that would be considered a megadrought or pluvial event today are projected to become average. Time-of-emergence calculations suggest that in some regions including Europe and western North America, this shift may have already taken place and could be imminent elsewhere: Emergence of drought/pluvial conditions occurs over 61% of the global land surface (excluding Antarctica) by 2080. Relative to the changing baseline, megadrought/megapluvial risk either will not change or is slightly reduced. However, the increased frequency and intensity of both extreme wet and dry precipitation events will likely present adaptation challenges beyond anything currently experienced. In many regions, resilience against future hazards will require adapting to an ever-changing “normal,” characterized by unprecedented aridification/wetting punctuated by more severe extremes.
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