1
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Esper J, Torbenson M, Büntgen U. 2023 summer warmth unparalleled over the past 2,000 years. Nature 2024; 631:94-97. [PMID: 38744323 DOI: 10.1038/s41586-024-07512-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 05/02/2024] [Indexed: 05/16/2024]
Abstract
Including an exceptionally warm Northern Hemisphere summer1,2, 2023 has been reported as the hottest year on record3-5. However, contextualizing recent anthropogenic warming against past natural variability is challenging because the sparse meteorological records from the nineteenth century tend to overestimate temperatures6. Here we combine observed and reconstructed June-August surface air temperatures to show that 2023 was the warmest Northern Hemisphere extra-tropical summer over the past 2,000 years exceeding the 95% confidence range of natural climate variability by more than 0.5 °C. Comparison of the 2023 June-August warming against the coldest reconstructed summer in CE 536 shows a maximum range of pre-Anthropocene-to-2023 temperatures of 3.93 °C. Although 2023 is consistent with a greenhouse-gases-induced warming trend7 that is amplified by an unfolding El Niño event8, this extreme emphasizes the urgency to implement international agreements for carbon emission reduction.
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Affiliation(s)
- Jan Esper
- Department of Geography, Johannes Gutenberg University, Mainz, Germany.
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic.
| | - Max Torbenson
- Department of Geography, Johannes Gutenberg University, Mainz, Germany
| | - Ulf Büntgen
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
- Department of Geography, University of Cambridge, Cambridge, UK
- Department of Geography, Masaryk University, Brno, Czech Republic
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2
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Chen F, Wang T, Zhao X, Esper J, Ljungqvist FC, Büntgen U, Linderholm HW, Meko D, Xu H, Yue W, Wang S, Yuan Y, Zheng J, Pan W, Roig F, Hadad M, Hu M, Wei J, Chen F. Coupled Pacific Rim megadroughts contributed to the fall of the Ming Dynasty's capital in 1644 CE. Sci Bull (Beijing) 2024:S2095-9273(24)00263-9. [PMID: 38811339 DOI: 10.1016/j.scib.2024.04.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 03/25/2024] [Accepted: 03/26/2024] [Indexed: 05/31/2024]
Abstract
Historical documents provide evidence for regional droughts preceding the political turmoil and fall of Beijing in 1644 CE, when more than 20 million people died in northern China during the late Ming famine period. However, the role climate and environmental changes may have played in this pivotal event in Chinese history remains unclear. Here, we provide tree-ring evidence of persistent megadroughts from 1576 to 1593 CE and from 1624 to 1643 CE in northern China, which coincided with exceptionally cold summers just before the fall of Beijing. Our analysis reveals that these regional hydroclimatic extremes are part of a series of megadroughts along the Pacific Rim, which not only impacted the ecology and society of monsoonal northern China, but likely also exacerbated external geopolitical and economic pressures. This finding is corroborated by last millennium reanalysis data and numerical climate model simulations revealing internally driven Pacific sea surface temperature variations and the predominance of decadal scale La Niña-like conditions to be responsible for precipitation decreases over northern China, as well as extensive monsoon regions in the Americas. These teleconnection patterns provide a mechanistic explanation for reoccurring drought spells during the late Ming Dynasty and the environmental framework fostering the fall of Beijing in 1644 CE, and the subsequent demise of the Ming Dynasty.
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Affiliation(s)
- Feng Chen
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China; Southwest United Graduate School, Kunming 650504, China.
| | - Tao Wang
- Climate Change Research Center and Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Chinese Academy of Sciences (CAS), Beijing 100029, China
| | - Xiaoen Zhao
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China; Southwest United Graduate School, Kunming 650504, China
| | - Jan Esper
- Department of Geography, Johannes Gutenberg University, Mainz 55099, Germany; Global Change Research Institute (CzechGlobe), Czech Academy of Sciences, Brno 60300, Czech Republic
| | - Fredrik Charpentier Ljungqvist
- Department of History, Stockholm University, Stockholm 10691, Sweden; Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden; Swedish Collegium for Advanced Study, Linneanum, Thunbergsvägen 2, Uppsala 75238, Sweden
| | - Ulf Büntgen
- Department of Geography, University of Cambridge, Cambridge CB2 3EN, UK; Global Change Research Institute (CzechGlobe), Czech Academy of Sciences, Brno 60300, Czech Republic; Department of Geography, Faculty of Science, Masaryk University, Brno 61137, Czech Republic; Swiss Federal Research Institute (WSL), Birmensdorf 8903, Switzerland
| | - Hans W Linderholm
- Regional Climate Group, Department of Earth Sciences, University of Gothenburg, Gothenburg 40530, Sweden
| | - David Meko
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ 85721, USA
| | - Hongna Xu
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC‑FEMD), Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Weipeng Yue
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China
| | - Shijie Wang
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China; Southwest United Graduate School, Kunming 650504, China
| | - Yujiang Yuan
- Key Laboratory of Tree-ring Physical and Chemical Research, Institute of Desert Meteorology, China Meteorological Administration, Urumqi 830002, China
| | - Jingyun Zheng
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Wei Pan
- Key Laboratory of Digital Human Technology R&D and Application of Yunnan Provincial Department of Education, Yunnan University, Kunming 650504, China
| | - Fidel Roig
- Laboratorio de Dendrocronología e Historia Ambiental, IANIGLA-CCT CONICET-Universidad Nacional de Cuyo, Mendoza 5500, Argentina; Hémera Centro de Observación de La Tierra, Escuela de Ingeniería ForestalFacultad de Ciencias, Universidad Mayor, Huechuraba 8580745, Santiago, Chile
| | - Martín Hadad
- Laboratorio de Dendrocronología de Zonas Áridas CIGEOBIO (CONICET-UNSJ), Gabinete de Geología Ambiental (INGEO-UNSJ), San Juan 3306, Argentina
| | - Mao Hu
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China; Southwest United Graduate School, Kunming 650504, China
| | - Jiachang Wei
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China
| | - Fahu Chen
- ALPHA, State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research (ITPCAS), Chinese Academy of Sciences (CAS), Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; MOE Key Laboratory of Western China's Environmental System, Lanzhou University, Lanzhou 730000, China
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3
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Kirdyanov AV, Saurer M, Arzac A, Knorre AA, Prokushkin AS, Churakova Sidorova OV, Arosio T, Bebchuk T, Siegwolf R, Büntgen U. Thawing permafrost can mitigate warming-induced drought stress in boreal forest trees. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168858. [PMID: 38030001 DOI: 10.1016/j.scitotenv.2023.168858] [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: 09/17/2023] [Revised: 11/21/2023] [Accepted: 11/23/2023] [Indexed: 12/01/2023]
Abstract
Perennially frozen soil, also known as permafrost, is important for the functioning and productivity of most of the boreal forest, the world's largest terrestrial biome. A better understanding of complex vegetation-permafrost interrelationships is needed to predict changes in local- to large-scale carbon, nutrient, and water cycle dynamics under future global warming. Here, we analyze tree-ring width and tree-ring stable isotope (C and O) measurements of Gmelin larch (Larix gmelinii (Rupr.) Rupr.) from six permafrost sites in the northern taiga of central Siberia. Our multi-parameter approach shows that changes in tree growth were predominantly controlled by the air and topsoil temperature and moisture content of the active soil and upper permafrost layers. The observed patterns range from strong growth limitations by early summer temperatures at higher elevations to significant growth controls by precipitation at warmer and well-drained lower-elevation sites. Enhanced radial tree growth is mainly found at sites with fast thawing upper mineral soil layers, and the comparison of tree-ring isotopes over five-year periods with different amounts of summer precipitation indicates that trees can prevent drought stress by accessing water from melted snow and seasonally frozen soil. Identifying the active soil and upper permafrost layers as central water resources for boreal tree growth during dry summers demonstrates the complexity of ecosystem responses to climatic changes.
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Affiliation(s)
- Alexander V Kirdyanov
- Department of Geography, University of Cambridge, CB2 3EN, UK; Sukachev Institute of Forest SB RAS, Federal Research Center 'Krasnoyarsk Science Center SB RAS', 660036 Krasnoyarsk, Akademgorodok, Russian Federation; Siberian Federal University, 660041 Krasnoyarsk, Svobodnii 79, Russian Federation.
| | - Matthias Saurer
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903 Birmensdorf, Switzerland
| | - Alberto Arzac
- Siberian Federal University, 660041 Krasnoyarsk, Svobodnii 79, Russian Federation
| | - Anastasia A Knorre
- Siberian Federal University, 660041 Krasnoyarsk, Svobodnii 79, Russian Federation; National Park "Krasnoyarsk Stolby", Krasnoyarsk 660006, Russian Federation
| | - Anatoly S Prokushkin
- Sukachev Institute of Forest SB RAS, Federal Research Center 'Krasnoyarsk Science Center SB RAS', 660036 Krasnoyarsk, Akademgorodok, Russian Federation; Siberian Federal University, 660041 Krasnoyarsk, Svobodnii 79, Russian Federation
| | - Olga V Churakova Sidorova
- Siberian Federal University, 660041 Krasnoyarsk, Svobodnii 79, Russian Federation; Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903 Birmensdorf, Switzerland
| | - Tito Arosio
- Department of Geography, University of Cambridge, CB2 3EN, UK
| | - Tatiana Bebchuk
- Department of Geography, University of Cambridge, CB2 3EN, UK
| | - Rolf Siegwolf
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903 Birmensdorf, Switzerland
| | - Ulf Büntgen
- Department of Geography, University of Cambridge, CB2 3EN, UK; Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903 Birmensdorf, Switzerland; Department of Geography, Masaryk University, 61137 Brno, Czech Republic; Global Change Research Centre, 61300 Brno, Czech Republic
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4
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Büntgen U, Rees G. Global change research needs international collaboration. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 902:166054. [PMID: 37543344 DOI: 10.1016/j.scitotenv.2023.166054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/21/2023] [Accepted: 08/02/2023] [Indexed: 08/07/2023]
Abstract
Tackling the grand challenges of global climate change for the sustainability of ecological and societal systems requires data and expertise from Russia, the world's largest country that has the longest Arctic shoreline and the largest forest biome, peatland and permafrost zones. Academic relations and scientific collaborations with Russian scholars and institutions must continue despite the ensuing geopolitical crisis since 2022.
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Affiliation(s)
- Ulf Büntgen
- Department of Geography, University of Cambridge, Cambridge CB2 3EN, UK; Global Change Research Institute of the Czech Academy of Sciences (CzechGlobe), 603 00 Brno, Czech Republic; Swiss Federal Research Institute (WSL), 8903 Birmensdorf, Switzerland; Department of Geography, Faculty of Science, Masaryk University, 613 00 Brno, Czech Republic.
| | - Gareth Rees
- Department of Geography, University of Cambridge, Cambridge CB2 3EN, UK; Scott Polar Research Institute, University of Cambridge, Cambridge CB2 3EN, UK; Department of Technology and Safety, UiT the Arctic University of Norway, 9019 Tromsø, Norway
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5
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Torbenson MC, Brázdil R, Stagge JH, Esper J, Büntgen U, Vizina A, Hanel M, Rakovec O, Fischer M, Urban O, Treml V, Reinig F, Martinez del Castillo E, Rybníček M, Kolář T, Trnka M. Increasing volatility of reconstructed Morava River warm-season flow, Czech Republic. JOURNAL OF HYDROLOGY. REGIONAL STUDIES 2023; 50:101534. [PMID: 38145056 PMCID: PMC10739599 DOI: 10.1016/j.ejrh.2023.101534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 09/13/2023] [Accepted: 09/19/2023] [Indexed: 12/26/2023]
Abstract
Study region The Morava River basin, Czech Republic, Danube Basin, Central Europe. Study focus Hydrological summer extremes represent a prominent natural hazard in Central Europe. River low flows constrain transport and water supply for agriculture, industry and society, and flood events are known to cause material damage and human loss. However, understanding changes in the frequency and magnitude of hydrological extremes is associated with great uncertainty due to the limited number of gauge observations. Here, we compile a tree-ring network to reconstruct the July-September baseflow variability of the Morava River from 1745 to 2018 CE. An ensemble of reconstructions was produced to assess the impact of calibration period length and trend on the long-term mean of reconstruction estimates. The final estimates represent the first baseflow reconstruction based on tree rings from the European continent. Simulated flows and historical documentation provide quantitative and qualitative validation of estimates prior to the 20th century. New hydrological insights for the region The reconstructions indicate an increased variability of warm-season flow during the past 100 years, with the most extreme high and low flows occurring after the start of instrumental observations. When analyzing the entire reconstruction, the negative trend in baseflow displayed by gauges across the basin after 1960 is not unprecedented. We conjecture that even lower flows could likely occur in the future considering that pre-instrumental trends were not primarily driven by rising temperature (and the evaporative demand) in contrast to the recent trends.
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Affiliation(s)
- Max C.A. Torbenson
- Department of Geography, Johannes Gutenberg University, Mainz, Germany
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
| | - Rudolf Brázdil
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
- Department of Geography, Masaryk University, Brno, Czech Republic
| | - James H. Stagge
- Department of Civil, Environmental, and Geodetic Engineering, Ohio State University, United States
| | - Jan Esper
- Department of Geography, Johannes Gutenberg University, Mainz, Germany
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
| | - Ulf Büntgen
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
- Department of Geography, Masaryk University, Brno, Czech Republic
- Department of Geography, University of Cambridge, Cambridge, UK
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Adam Vizina
- T.G. Masaryk Water Research Institute, Prague, Czech Republic
- Department of Water Resources and Environmental Modeling, Czech University of Life Sciences, Prague, Czech Republic
| | - Martin Hanel
- Department of Water Resources and Environmental Modeling, Czech University of Life Sciences, Prague, Czech Republic
| | - Oldrich Rakovec
- Department of Water Resources and Environmental Modeling, Czech University of Life Sciences, Prague, Czech Republic
- UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Milan Fischer
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
- Department of Agrosystems and Bioclimatology, Mendel University in Brno, Brno, Czech Republic
| | - Otmar Urban
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
| | - Václav Treml
- Department of Physical Geography and Geoecology, Charles University, Prague, Czech Republic
| | - Frederick Reinig
- Department of Geography, Johannes Gutenberg University, Mainz, Germany
| | | | - Michal Rybníček
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
- Department of Wood Science and Wood Technology, Mendel University in Brno, Brno, Czech Republic
| | - Tomáš Kolář
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
- Department of Wood Science and Wood Technology, Mendel University in Brno, Brno, Czech Republic
| | - Miroslav Trnka
- Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic
- Department of Agrosystems and Bioclimatology, Mendel University in Brno, Brno, Czech Republic
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6
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Bogachev MI, Gafurov AM, Iskandirov PY, Kaplun DI, Kayumov AR, Lyanova AI, Pyko NS, Pyko SA, Safonova AN, Sinitca AM, Usmanov BM, Tishin DV. Reversal in the drought stress response of the Scots pine forest ecosystem: Local soil water regime as a key to improving climate change resilience. Heliyon 2023; 9:e21574. [PMID: 37954317 PMCID: PMC10638002 DOI: 10.1016/j.heliyon.2023.e21574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 10/13/2023] [Accepted: 10/24/2023] [Indexed: 11/14/2023] Open
Abstract
In a changing climate, forest ecosystems have become increasingly vulnerable to continuously exacerbating heat and associated drought conditions. Climate stress resilience is governed by a complex interplay of global, regional, and local factors, with hydrological conditions being among the key players. We studied a Scots pine (Pinus sylvestris L.) forest ecosystem located near the southern edge of the boreal ecotone, which is particularly subjected to frequent and prolonged droughts. By comparing the dendrochronological series of pines growing in apparently contrasting hydrological conditions ranging from the waterlogged peat bog area to the dry soil at the surrounding elevations, we investigated how the soil water regime affects the climate response and drought stress resilience of the forest ecosystem. We found that in the dry land area, a significant fraction of the trees were replaced after two major climate extremes: prolonged drought and extremely low winter temperatures. The latter has also been followed by a three- to ten-fold growth reduction of the trees that survived in the next year, whereas no similar effect has been observed in the peat bog area. Multi-scale detrended partial cross-correlation analysis (DPCCA) indicated that tree-ring width (TRW) was negatively correlated with spring and summer temperatures and positively correlated with the Palmer drought severity index (PDSI) for the same year. For the elevated dry land area, the above effect extends to interannual scales, indicating that prolonged heatwaves and associated droughts are among the factors that limit tree growth. In marked contrast, in the waterlogged peat bog area, a reversed tendency was observed, with prolonged dry periods as well as warmer springs and summers over several consecutive years, leading to increasing tree growth with a one- to three-year time lag. Altogether, our results indicate that the pessimal conditions of a warming climate could become favorable through the preservation of the soil water regime.
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Affiliation(s)
- Mikhail I. Bogachev
- St. Petersburg Electrotechnical University “LETI”, 5-F Professor Popov street, St. Petersburg, 197022, Russia
| | - Artur M. Gafurov
- Kazan Federal University, 18 Kremlevskaya street, Kazan, Tatarstan, 420008, Russia
| | - Pavel Y. Iskandirov
- Kazan Federal University, 18 Kremlevskaya street, Kazan, Tatarstan, 420008, Russia
| | - Dmitrii I. Kaplun
- St. Petersburg Electrotechnical University “LETI”, 5-F Professor Popov street, St. Petersburg, 197022, Russia
| | - Airat R. Kayumov
- Kazan Federal University, 18 Kremlevskaya street, Kazan, Tatarstan, 420008, Russia
| | - Asya I. Lyanova
- St. Petersburg Electrotechnical University “LETI”, 5-F Professor Popov street, St. Petersburg, 197022, Russia
| | - Nikita S. Pyko
- St. Petersburg Electrotechnical University “LETI”, 5-F Professor Popov street, St. Petersburg, 197022, Russia
| | - Svetlana A. Pyko
- St. Petersburg Electrotechnical University “LETI”, 5-F Professor Popov street, St. Petersburg, 197022, Russia
| | - Anastasiia N. Safonova
- St. Petersburg Electrotechnical University “LETI”, 5-F Professor Popov street, St. Petersburg, 197022, Russia
| | - Aleksandr M. Sinitca
- St. Petersburg Electrotechnical University “LETI”, 5-F Professor Popov street, St. Petersburg, 197022, Russia
| | - Bulat M. Usmanov
- Kazan Federal University, 18 Kremlevskaya street, Kazan, Tatarstan, 420008, Russia
| | - Denis V. Tishin
- St. Petersburg Electrotechnical University “LETI”, 5-F Professor Popov street, St. Petersburg, 197022, Russia
- Kazan Federal University, 18 Kremlevskaya street, Kazan, Tatarstan, 420008, Russia
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7
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Camuera J, Jiménez-Espejo FJ, Soto-Chica J, Jiménez-Moreno G, García-Alix A, Ramos-Román MJ, Ruha L, Castro-Priego M. Drought as a possible contributor to the Visigothic Kingdom crisis and Islamic expansion in the Iberian Peninsula. Nat Commun 2023; 14:5733. [PMID: 37714827 PMCID: PMC10504262 DOI: 10.1038/s41467-023-41367-7] [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: 11/08/2022] [Accepted: 09/01/2023] [Indexed: 09/17/2023] Open
Abstract
The Muslim expansion in the Mediterranean basin was one the most relevant and rapid cultural changes in human history. This expansion reached the Iberian Peninsula with the replacement of the Visigothic Kingdom by the Muslim Umayyad Caliphate and the Muslim Emirate of Córdoba during the 8th century CE. In this study we made a compilation of western Mediterranean pollen records to gain insight about past climate conditions when this expansion took place. The pollen stack results, together with other paleohydrological records, archaeological data and historical sources, indicate that the statistically significant strongest droughts between the mid-5th and mid-10th centuries CE (450-950 CE) occurred at 545-570, 695-725, 755-770 and 900-935 CE, which could have contributed to the instability of the Visigothic and Muslim reigns in the Iberian Peninsula. Our study supports the great sensitivity of the agriculture-based economy and socio-political unrest of Early Medieval kingdoms to climatic variations.
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Affiliation(s)
- Jon Camuera
- Andalusian Earth Sciences Institute (IACT), Spanish National Research Council - University of Granada (CSIC-UGR), Granada, Spain.
| | - Francisco J Jiménez-Espejo
- Andalusian Earth Sciences Institute (IACT), Spanish National Research Council - University of Granada (CSIC-UGR), Granada, Spain.
| | - José Soto-Chica
- Department of Medieval History and Historiographic Sciences and Techniques, University of Granada, Granada, Spain
| | - Gonzalo Jiménez-Moreno
- Department of Stratigraphy and Paleontology, Faculty of Science, University of Granada, Granada, Spain
| | - Antonio García-Alix
- Department of Stratigraphy and Paleontology, Faculty of Science, University of Granada, Granada, Spain
| | | | - Leena Ruha
- Natural Resources Institute Finland, Oulu, Finland
- Research Unit of Mathematical Sciences, University of Oulu, Oulu, Finland
| | - Manuel Castro-Priego
- Unit of Archaeology, Department of History and Philosophy, University of Alcalá, Alcalá de Henares, Spain
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8
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Zhu F, Emile-Geay J, Anchukaitis KJ, McKay NP, Stevenson S, Meng Z. A pseudoproxy emulation of the PAGES 2k database using a hierarchy of proxy system models. Sci Data 2023; 10:624. [PMID: 37709805 PMCID: PMC10502095 DOI: 10.1038/s41597-023-02489-1] [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: 05/01/2023] [Accepted: 08/18/2023] [Indexed: 09/16/2023] Open
Abstract
Paleoclimate reconstructions are now integral to climate assessments, yet the consequences of using different methodologies and proxy data require rigorous benchmarking. Pseudoproxy experiments (PPEs) provide a tractable and transparent test bed for evaluating climate reconstruction methods and their sensitivity to aspects of real-world proxy networks. Here we develop a dataset that leverages proxy system models (PSMs) for this purpose, which emulates the essential physical, chemical, biological, and geological processes that translate climate signals into proxy records, making these synthetic proxies more relevant to the real world. We apply a suite of PSMs to emulate the widely-used PAGES 2k dataset, including realistic spatiotemporal sampling and error structure. A hierarchical approach allows us to produce many variants of this base dataset, isolating the impact of sampling bias in time and space, representation error, sampling error, and other assumptions. Combining these various experiments produces a rich dataset ("pseudoPAGES2k") for many applications. As an illustration, we show how to conduct a PPE with this dataset based on emerging climate field reconstruction techniques.
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Affiliation(s)
- Feng Zhu
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USA.
| | - Julien Emile-Geay
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, USA
| | - Kevin J Anchukaitis
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, USA
- School of Geography, Development, and Environment, University of Arizona, Tucson, AZ, USA
| | - Nicholas P McKay
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, AZ, USA
| | - Samantha Stevenson
- Bren School of Environmental Science and Management, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Zilu Meng
- Department of Atmospheric Sciences, University of Washington, Seattle, WA, USA
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9
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Björklund J, Seftigen K, Stoffel M, Fonti MV, Kottlow S, Frank DC, Esper J, Fonti P, Goosse H, Grudd H, Gunnarson BE, Nievergelt D, Pellizzari E, Carrer M, von Arx G. Fennoscandian tree-ring anatomy shows a warmer modern than medieval climate. Nature 2023; 620:97-103. [PMID: 37532816 DOI: 10.1038/s41586-023-06176-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 05/05/2023] [Indexed: 08/04/2023]
Abstract
Earth system models and various climate proxy sources indicate global warming is unprecedented during at least the Common Era1. However, tree-ring proxies often estimate temperatures during the Medieval Climate Anomaly (950-1250 CE) that are similar to, or exceed, those recorded for the past century2,3, in contrast to simulation experiments at regional scales4. This not only calls into question the reliability of models and proxies but also contributes to uncertainty in future climate projections5. Here we show that the current climate of the Fennoscandian Peninsula is substantially warmer than that of the medieval period. This highlights the dominant role of anthropogenic forcing in climate warming even at the regional scale, thereby reconciling inconsistencies between reconstructions and model simulations. We used an annually resolved 1,170-year-long tree-ring record that relies exclusively on tracheid anatomical measurements from Pinus sylvestris trees, providing high-fidelity measurements of instrumental temperature variability during the warm season. We therefore call for the construction of more such millennia-long records to further improve our understanding and reduce uncertainties around historical and future climate change at inter-regional and eventually global scales.
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Affiliation(s)
- Jesper Björklund
- Swiss Federal Institute for Forest Snow and Landscape Research WSL, Birmensdorf, Switzerland.
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland.
| | - Kristina Seftigen
- Swiss Federal Institute for Forest Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Regional Climate Group, Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Markus Stoffel
- Climate Change Impacts and Risks in the Anthropocene (C-CIA), University of Geneva, Geneva, Switzerland
- Dendrolab.ch, Department of Earth Sciences, University of Geneva, Geneva, Switzerland
- Department F.-A. Forel for Environmental and Aquatic Sciences, University of Geneva, Geneva, Switzerland
| | - Marina V Fonti
- Swiss Federal Institute for Forest Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Sven Kottlow
- Swiss Federal Institute for Forest Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - David C Frank
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, USA
| | - Jan Esper
- Department of Geography, Johannes Gutenberg University, Mainz, Germany
- Global Change Research Institute of the Czech Academy of Sciences (CzechGlobe), Brno, Czech Republic
| | - Patrick Fonti
- Swiss Federal Institute for Forest Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Hugues Goosse
- Earth and Life Institute, Université Catholique de Louvain (UCLouvain), Louvain-la-Neuve, Belgium
| | - Håkan Grudd
- Swedish Polar Research Secretariat, Abisko Scientific Research Station, Abisko, Sweden
| | - Björn E Gunnarson
- Department of Physical Geography, Stockholm University, Stockholm, Sweden
- Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
| | - Daniel Nievergelt
- Swiss Federal Institute for Forest Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Elena Pellizzari
- Department of Land, Environment, Agriculture and Forestry (TeSAF), University of Padua, Padua, Italy
| | - Marco Carrer
- Department of Land, Environment, Agriculture and Forestry (TeSAF), University of Padua, Padua, Italy
| | - Georg von Arx
- Swiss Federal Institute for Forest Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
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10
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Diodato N, Ljungqvist FC, Bellocchi G. Historical information sheds new light on the intensification of flooding in the Central Mediterranean. Sci Rep 2023; 13:10664. [PMID: 37393322 PMCID: PMC10314911 DOI: 10.1038/s41598-023-37683-z] [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: 04/06/2023] [Accepted: 06/26/2023] [Indexed: 07/03/2023] Open
Abstract
Hydrological disasters, such as floods, can have dire consequences for human societies. Historical information plays a key role in detecting whether particular types of hydrological disasters have increased in frequency and/or magnitude and, if so, they are more likely attributable to natural or human-induced climatic and other environmental changes. The identification of regions with similar flood conditions is essential for the analysis of regional flooding regimes. To this end, we here present the longest existing flood reconstruction for the Eastern Liguria Area (ELA) in northwestern Italy, covering 1582 to 2022 CE, which offers a case study representative of the central Mediterranean region. An Annual Flood Intensification Index was developed to transform the historical data into a continuous annual hydrological time-series contained by a homogeneous data structure for the study-area. We found two change-points (trend breaks) in the reconstructed time-series, in 1787 and 1967, with only occasional heavy floods comparable to present-day disasters occurring before the first change-point, and an increasing intensification of floods after the second change-point up to the present day. The recent intensification of flooding in the ELA, associated with changes in land use and land cover, also appears to coincide with phases in which hydrological hazards have become more changeable and extreme in disaster-affected areas. This is evidenced by river basin responses to human-induced disturbances.
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Affiliation(s)
- Nazzareno Diodato
- Met European Research Observatory - International Affiliates Program of the University Corporation for Atmospheric Research, Benevento, Italy
| | - Fredrik Charpentier Ljungqvist
- Department of History, Stockholm University, 106 91, Stockholm, Sweden.
- Bolin Centre for Climate Research, Stockholm University, 106 91, Stockholm, Sweden.
- Swedish Collegium for Advanced Study, Linneanum, Thunbergsvägen 2, 752 38, Uppsala, Sweden.
| | - Gianni Bellocchi
- Met European Research Observatory - International Affiliates Program of the University Corporation for Atmospheric Research, Benevento, Italy
- Université Clermont Auvergne, INRAE, VetAgro Sup, UREP, Clermont-Ferrand, France
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11
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Guillet S, Corona C, Oppenheimer C, Lavigne F, Khodri M, Ludlow F, Sigl M, Toohey M, Atkins PS, Yang Z, Muranaka T, Horikawa N, Stoffel M. Lunar eclipses illuminate timing and climate impact of medieval volcanism. Nature 2023; 616:90-95. [PMID: 37020006 PMCID: PMC10076221 DOI: 10.1038/s41586-023-05751-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 01/20/2023] [Indexed: 04/07/2023]
Abstract
Explosive volcanism is a key contributor to climate variability on interannual to centennial timescales1. Understanding the far-field societal impacts of eruption-forced climatic changes requires firm event chronologies and reliable estimates of both the burden and altitude (that is, tropospheric versus stratospheric) of volcanic sulfate aerosol2,3. However, despite progress in ice-core dating, uncertainties remain in these key factors4. This particularly hinders investigation of the role of large, temporally clustered eruptions during the High Medieval Period (HMP, 1100-1300 CE), which have been implicated in the transition from the warm Medieval Climate Anomaly to the Little Ice Age5. Here we shed new light on explosive volcanism during the HMP, drawing on analysis of contemporary reports of total lunar eclipses, from which we derive a time series of stratospheric turbidity. By combining this new record with aerosol model simulations and tree-ring-based climate proxies, we refine the estimated dates of five notable eruptions and associate each with stratospheric aerosol veils. Five further eruptions, including one responsible for high sulfur deposition over Greenland circa 1182 CE, affected only the troposphere and had muted climatic consequences. Our findings offer support for further investigation of the decadal-scale to centennial-scale climate response to volcanic eruptions.
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Affiliation(s)
- Sébastien Guillet
- Climate Change Impacts and Risks in the Anthropocene (C-CIA), Institute for Environmental Sciences, University of Geneva, Geneva, Switzerland.
| | - Christophe Corona
- Climate Change Impacts and Risks in the Anthropocene (C-CIA), Institute for Environmental Sciences, University of Geneva, Geneva, Switzerland
- GEOLAB, Université Clermont Auvergne, CNRS, Clermont-Ferrand, France
| | | | - Franck Lavigne
- Laboratoire de Géographie Physique, Université Paris 1 Panthéon-Sorbonne, Thiais, France
| | - Myriam Khodri
- Laboratoire d'Océanographie et du Climat: Expérimentations et Approches Numériques, IPSL, Sorbonne Université/IRD/CNRS/MNHN, Paris, France
| | - Francis Ludlow
- Trinity Centre for Environmental Humanities, Department of History, School of Histories & Humanities, Trinity College Dublin, Dublin, Ireland
| | - Michael Sigl
- Climate and Environmental Physics, University of Bern, Bern, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Matthew Toohey
- Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Paul S Atkins
- Department of Asian Languages & Literature, University of Washington, Seattle, WA, USA
| | - Zhen Yang
- Trinity Centre for Environmental Humanities, Department of History, School of Histories & Humanities, Trinity College Dublin, Dublin, Ireland
| | - Tomoko Muranaka
- Climate Change Impacts and Risks in the Anthropocene (C-CIA), Institute for Environmental Sciences, University of Geneva, Geneva, Switzerland
| | - Nobuko Horikawa
- Department of Asian Languages & Literature, University of Washington, Seattle, WA, USA
| | - Markus Stoffel
- Climate Change Impacts and Risks in the Anthropocene (C-CIA), Institute for Environmental Sciences, University of Geneva, Geneva, Switzerland
- Department of Earth Sciences, University of Geneva, Geneva, Switzerland
- Department F.-A. Forel for Environmental and Aquatic Sciences, University of Geneva, Geneva, Switzerland
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12
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Severe multi-year drought coincident with Hittite collapse around 1198-1196 BC. Nature 2023; 614:719-724. [PMID: 36755095 PMCID: PMC9946833 DOI: 10.1038/s41586-022-05693-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 12/30/2022] [Indexed: 02/10/2023]
Abstract
The potential of climate change to substantially alter human history is a pressing concern, but the specific effects of different types of climate change remain unknown. This question can be addressed using palaeoclimatic and archaeological data. For instance, a 300-year, low-frequency shift to drier, cooler climate conditions around 1200 BC is frequently associated with the collapse of several ancient civilizations in the Eastern Mediterranean and Near East1-4. However, the precise details of synchronized climate and human-history-scale associations are lacking. The archaeological-historical record contains multiple instances of human societies successfully adapting to low-frequency climate change5-7. It is likely that consecutive multi-year occurrences of rare, unexpected extreme climatic events may push a population beyond adaptation and centuries-old resilience practices5,7-10. Here we examine the collapse of the Hittite Empire around 1200 BC. The Hittites were one of the great powers in the ancient world across five centuries11-14, with an empire centred in a semi-arid region in Anatolia with political and socioeconomic interconnections throughout the ancient Near East and Eastern Mediterranean, which for a long time proved resilient despite facing regular and intersecting sociopolitical, economic and environmental challenges. Examination of ring width and stable isotope records obtained from contemporary juniper trees in central Anatolia provides a high-resolution dryness record. This analysis identifies an unusually severe continuous dry period from around 1198 to 1196 (±3) BC, potentially indicating a tipping point, and signals the type of episode that can overwhelm contemporary risk-buffering practices.
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13
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Arsalani M, Grießinger J, Bräuning A. Tree-ring-based seasonal temperature reconstructions and ecological implications of recent warming on oak forest health in the Zagros Mountains, Iran. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2022; 66:2553-2565. [PMID: 36214884 PMCID: PMC9684230 DOI: 10.1007/s00484-022-02380-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 09/01/2022] [Accepted: 10/01/2022] [Indexed: 06/16/2023]
Abstract
Abrupt changes in temperature have especially strong impacts on fragile ecosystems located in semi-arid regions. In this study, we analyzed tree-ring widths (TRW) of Mediterranean cypress (Cupressus sempervirens var. horizontalis) in the Zagros Mountains, Iran. Furthermore, we separately measured earlywood width (EWW) and latewood width (LWW) of Persian oak (Quercus brantii Lindl.) to examine if intra-annual resolution of tree-ring parameters of Q. brantii tree rings can be used as high-resolution paleoclimate proxies. Climate-growth relationships revealed that mean monthly maximum temperatures (Tmax) are a dominant factor determining radial tree growth and negatively affect both oak and cypress in the Zagros Mountains. Accordingly, we reconstructed two different seasonal windows of past Tmax variability, namely, January-March and June-August over the periods 1860-2015 and 1560-2015, respectively. Regime shift detection identified twelve warm and nine cold significant regime shifts in our summer Tmax reconstructions. The longest hot summer period occurred in the twentieth century, and two warm regime shifts occurred in 1999 and 2008. The highest values of the warm summer regime shift index occurred in 2008, which coincided with fungal pathogen attacks and insect outbreak of the oak leaf roller moth (Tortrix viridana L.) in the Zagros oak woodlands. Interestingly, we found common warm and cold periods in historic climate variability between the summer and winter Tmax reconstructions. Warm and cold regime shifts occurred simultaneously from 1955 to 2015, and significant regional warm summer and winter regime shifts have occurred between 2008 and 2015. The winter and summer Tmax reconstructions show high spatial correlations with large areas in West Asia, North Africa, and the eastern Mediterranean region. Our results strengthen initial studies on past climate variability in Iran and contribute to an enhanced understanding of past temperature variability in West Asia.
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Affiliation(s)
- Mohsen Arsalani
- Institute of Geography, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Wetterkreuz 15, 91058 Erlangen, Germany
| | - Jussi Grießinger
- Institute of Geography, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Wetterkreuz 15, 91058 Erlangen, Germany
| | - Achim Bräuning
- Institute of Geography, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Wetterkreuz 15, 91058 Erlangen, Germany
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14
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Global wood anatomical perspective on the onset of the Late Antique Little Ice Age (LALIA) in the mid-6th century CE. Sci Bull (Beijing) 2022; 67:2336-2344. [PMID: 36546223 DOI: 10.1016/j.scib.2022.10.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 11/06/2022]
Abstract
Linked to major volcanic eruptions around 536 and 540 CE, the onset of the Late Antique Little Ice Age has been described as the coldest period of the past two millennia. The exact timing and spatial extent of this exceptional cold phase are, however, still under debate because of the limited resolution and geographical distribution of the available proxy archives. Here, we use 106 wood anatomical thin sections from 23 forest sites and 20 tree species in both hemispheres to search for cell-level fingerprints of ephemeral summer cooling between 530 and 550 CE. After cross-dating and double-staining, we identified 89 Blue Rings (lack of cell wall lignification), nine Frost Rings (cell deformation and collapse), and 93 Light Rings (reduced cell wall thickening) in the Northern Hemisphere. Our network reveals evidence for the strongest temperature depression between mid-July and early-August 536 CE across North America and Eurasia, whereas more localised cold spells occurred in the summers of 532, 540-43, and 548 CE. The lack of anatomical signatures in the austral trees suggests limited incursion of stratospheric volcanic aerosol into the Southern Hemisphere extra-tropics, that any forcing was mitigated by atmosphere-ocean dynamical responses and/or concentrated outside the growing season, or a combination of factors. Our findings demonstrate the advantage of wood anatomical investigations over traditional dendrochronological measurements, provide a benchmark for Earth system models, support cross-disciplinary studies into the entanglements of climate and history, and question the relevance of global climate averages.
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15
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Modern aridity in the Altai-Sayan mountain range derived from multiple millennial proxies. Sci Rep 2022; 12:7752. [PMID: 35562178 PMCID: PMC9095625 DOI: 10.1038/s41598-022-11299-1] [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: 02/07/2022] [Accepted: 04/11/2022] [Indexed: 11/18/2022] Open
Abstract
Temperature and precipitation changes are crucial for larch trees growing at high-elevation sites covered by permafrost in the Altai-Sayan mountain range (ASMR). To contextualize the amplitude of recent climate fluctuations, we have to look into the past by analyzing millennial paleoclimatic archives recording both temperature and precipitation. We developed annually resolved 1500-year tree-ring cellulose chronologies (δ13Ccell, δ18Ocell), and used these new records to reconstruct the variability in local summer precipitation and air temperature. We combined our new local reconstructions with existing paleoclimatic archives available for the Altai. The data show a strong decreasing trend by ca. 49% in regional summer precipitation, along with a regional summer temperature increase towards the twenty-first century, relative to the preceding 1500 years. Modern dry conditions (1966–2016 CE) in the ASMR are the result of simultaneous summer warming and decreased precipitation. Our new reconstructions also demonstrate that climate change in the ASMR is much stronger compared to the global average.
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16
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Abstract
Human evolution was strongly related to environmental factors. Woodlands and their products played a key role in the production of tools and weapons, and provided unique resources for constructions and fuel. Therefore wooden finds are essential in gaining insights into climatic and land use changes but also societal development during the Holocene. Dendroarchaeological investigations, based on tree rings, wood anatomy and techno-morphological characteristics are of great importance for a better understanding of past chronological processes as well as human-environment-interactions. Here we present an overview of the sources, methods, and concepts of this interdisciplinary field of dendroarchaeology focusing on Europe, where several tree-ring chronologies span most of the Holocene. We describe research examples from different periods of human history and discuss the current state of field. The long settlement history in Europe provides a myriad of wooden archeological samples not only for dating but also offer exciting new findings at the interface of natural and social sciences and the humanities.
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