Articles | Volume 22, issue 6
https://doi.org/10.5194/cp-22-1125-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-22-1125-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
05 Jun 2026
Research article |
| 05 Jun 2026
| 05 Jun 2026
Unravelling the tree cover dynamics over the last 20 000 years on the Northern Hemisphere
Anne Dallmeyer
CORRESPONDING AUTHOR
Max-Planck-Institute for Meteorology, 20146 Hamburg, Germany
Nils Weitzel
Research Center Trustworthy Data Science and Security of the University Alliance Ruhr, Dortmund, Germany
Department of Statistics, TU Dortmund University, Dortmund, Germany
School of Geographical Sciences, University of Bristol, Bristol, UK
Laura Schild
Helmholtz Centre for Polar and Marine Research, Research Unit Potsdam, Alfred Wegener Institute (AWI), Potsdam, Germany
Ulrike Herzschuh
Helmholtz Centre for Polar and Marine Research, Research Unit Potsdam, Alfred Wegener Institute (AWI), Potsdam, Germany
Institute of Environmental Sciences and Geography, University of Potsdam, Karl-Liebknecht-Straße 24–25, Potsdam, Germany
Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Straße 24–25, Potsdam, Germany
Thomas Kleinen
Max-Planck-Institute for Meteorology, 20146 Hamburg, Germany
Martin Claussen
Max-Planck-Institute for Meteorology, 20146 Hamburg, Germany
Meteorological Institute, Universität Hamburg, 20146 Hamburg, Germany
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Laura Schild, Peter Ewald, Chenzhi Li, Raphaël Hébert, Thomas Laepple, and Ulrike Herzschuh
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Marielle Saunois, Adrien Martinez, Benjamin Poulter, Zhen Zhang, Peter A. Raymond, Pierre Regnier, Josep G. Canadell, Robert B. Jackson, Prabir K. Patra, Philippe Bousquet, Philippe Ciais, Edward J. Dlugokencky, Xin Lan, George H. Allen, David Bastviken, David J. Beerling, Dmitry A. Belikov, Donald R. Blake, Simona Castaldi, Monica Crippa, Bridget R. Deemer, Fraser Dennison, Giuseppe Etiope, Nicola Gedney, Lena Höglund-Isaksson, Meredith A. Holgerson, Peter O. Hopcroft, Gustaf Hugelius, Akihiko Ito, Atul K. Jain, Rajesh Janardanan, Matthew S. Johnson, Thomas Kleinen, Paul B. Krummel, Ronny Lauerwald, Tingting Li, Xiangyu Liu, Kyle C. McDonald, Joe R. Melton, Jens Mühle, Jurek Müller, Fabiola Murguia-Flores, Yosuke Niwa, Sergio Noce, Shufen Pan, Robert J. Parker, Changhui Peng, Michel Ramonet, William J. Riley, Gerard Rocher-Ros, Judith A. Rosentreter, Motoki Sasakawa, Arjo Segers, Steven J. Smith, Emily H. Stanley, Joël Thanwerdas, Hanqin Tian, Aki Tsuruta, Francesco N. Tubiello, Thomas S. Weber, Guido R. van der Werf, Douglas E. J. Worthy, Yi Xi, Yukio Yoshida, Wenxin Zhang, Bo Zheng, Qing Zhu, Qiuan Zhu, and Qianlai Zhuang
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Tuula Aalto, Aki Tsuruta, Jarmo Mäkelä, Jurek Müller, Maria Tenkanen, Eleanor Burke, Sarah Chadburn, Yao Gao, Vilma Mannisenaho, Thomas Kleinen, Hanna Lee, Antti Leppänen, Tiina Markkanen, Stefano Materia, Paul A. Miller, Daniele Peano, Olli Peltola, Benjamin Poulter, Maarit Raivonen, Marielle Saunois, David Wårlind, and Sönke Zaehle
Biogeosciences, 22, 323–340, https://doi.org/10.5194/bg-22-323-2025, https://doi.org/10.5194/bg-22-323-2025, 2025
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Zhen Zhang, Benjamin Poulter, Joe R. Melton, William J. Riley, George H. Allen, David J. Beerling, Philippe Bousquet, Josep G. Canadell, Etienne Fluet-Chouinard, Philippe Ciais, Nicola Gedney, Peter O. Hopcroft, Akihiko Ito, Robert B. Jackson, Atul K. Jain, Katherine Jensen, Fortunat Joos, Thomas Kleinen, Sara H. Knox, Tingting Li, Xin Li, Xiangyu Liu, Kyle McDonald, Gavin McNicol, Paul A. Miller, Jurek Müller, Prabir K. Patra, Changhui Peng, Shushi Peng, Zhangcai Qin, Ryan M. Riggs, Marielle Saunois, Qing Sun, Hanqin Tian, Xiaoming Xu, Yuanzhi Yao, Yi Xi, Wenxin Zhang, Qing Zhu, Qiuan Zhu, and Qianlai Zhuang
Biogeosciences, 22, 305–321, https://doi.org/10.5194/bg-22-305-2025, https://doi.org/10.5194/bg-22-305-2025, 2025
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This study assesses global methane emissions from wetlands between 2000 and 2020 using multiple models. We found that wetland emissions increased by 6–7 Tg CH4 yr-1 in the 2010s compared to the 2000s. Rising temperatures primarily drove this increase, while changes in precipitation and CO2 levels also played roles. Our findings highlight the importance of wetlands in the global methane budget and the need for continuous monitoring to understand their impact on climate change.
Pin-Hsin Hu, Christian H. Reick, Reiner Schnur, Axel Kleidon, and Martin Claussen
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2024-111, https://doi.org/10.5194/gmd-2024-111, 2024
Revised manuscript accepted for GMD
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We introduce the new plant functional diversity model JeDi-BACH, a novel tool that integrates the Jena Diversity Model (JeDi) within the land component of the ICON Earth System Model. JeDi-BACH captures a richer set of plant trait variations based on environmental filtering and functional tradeoffs without a priori knowledge of the vegetation types. JeDi-BACH represents a significant advancement in modeling the complex interactions between plant functional diversity and climate.
Nora Farina Specht, Martin Claussen, and Thomas Kleinen
Clim. Past, 20, 1595–1613, https://doi.org/10.5194/cp-20-1595-2024, https://doi.org/10.5194/cp-20-1595-2024, 2024
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We close the terrestrial water cycle across the Sahara and Sahel by integrating a new endorheic-lake model into a climate model. A factor analysis of mid-Holocene simulations shows that both dynamic lakes and dynamic vegetation individually contribute to a precipitation increase over northern Africa that is collectively greater than that caused by the interaction between lake and vegetation dynamics. Thus, the lake–vegetation interaction causes a relative drying response across the entire Sahel.
Amelie Stieg, Boris K. Biskaborn, Ulrike Herzschuh, Jens Strauss, Luidmila Pestryakova, and Hanno Meyer
Clim. Past, 20, 909–933, https://doi.org/10.5194/cp-20-909-2024, https://doi.org/10.5194/cp-20-909-2024, 2024
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Siberia is impacted by recent climate warming and experiences extreme hydroclimate events. We present a 220-year-long sub-decadal stable oxygen isotope record of diatoms from Lake Khamra. Our analysis identifies winter precipitation as the key process impacting the isotope variability. Two possible hydroclimatic anomalies were found to coincide with significant changes in lake internal conditions and increased wildfire activity in the region.
Nils Weitzel, Heather Andres, Jean-Philippe Baudouin, Marie-Luise Kapsch, Uwe Mikolajewicz, Lukas Jonkers, Oliver Bothe, Elisa Ziegler, Thomas Kleinen, André Paul, and Kira Rehfeld
Clim. Past, 20, 865–890, https://doi.org/10.5194/cp-20-865-2024, https://doi.org/10.5194/cp-20-865-2024, 2024
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The ability of climate models to faithfully reproduce past warming episodes is a valuable test considering potentially large future warming. We develop a new method to compare simulations of the last deglaciation with temperature reconstructions. We find that reconstructions differ more between regions than simulations, potentially due to deficiencies in the simulation design, models, or reconstructions. Our work is a promising step towards benchmarking simulations of past climate transitions.
Philip Meister, Anne Alexandre, Hannah Bailey, Philip Barker, Boris K. Biskaborn, Ellie Broadman, Rosine Cartier, Bernhard Chapligin, Martine Couapel, Jonathan R. Dean, Bernhard Diekmann, Poppy Harding, Andrew C. G. Henderson, Armand Hernandez, Ulrike Herzschuh, Svetlana S. Kostrova, Jack Lacey, Melanie J. Leng, Andreas Lücke, Anson W. Mackay, Eniko Katalin Magyari, Biljana Narancic, Cécile Porchier, Gunhild Rosqvist, Aldo Shemesh, Corinne Sonzogni, George E. A. Swann, Florence Sylvestre, and Hanno Meyer
Clim. Past, 20, 363–392, https://doi.org/10.5194/cp-20-363-2024, https://doi.org/10.5194/cp-20-363-2024, 2024
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This paper presents the first comprehensive compilation of diatom oxygen isotope records in lake sediments (δ18OBSi), supported by lake basin parameters. We infer the spatial and temporal coverage of δ18OBSi records and discuss common hemispheric trends on centennial and millennial timescales. Key results are common patterns for hydrologically open lakes in Northern Hemisphere extratropical regions during the Holocene corresponding to known climatic epochs, i.e. the Holocene Thermal Maximum.
Nico Wunderling, Anna S. von der Heydt, Yevgeny Aksenov, Stephen Barker, Robbin Bastiaansen, Victor Brovkin, Maura Brunetti, Victor Couplet, Thomas Kleinen, Caroline H. Lear, Johannes Lohmann, Rosa Maria Roman-Cuesta, Sacha Sinet, Didier Swingedouw, Ricarda Winkelmann, Pallavi Anand, Jonathan Barichivich, Sebastian Bathiany, Mara Baudena, John T. Bruun, Cristiano M. Chiessi, Helen K. Coxall, David Docquier, Jonathan F. Donges, Swinda K. J. Falkena, Ann Kristin Klose, David Obura, Juan Rocha, Stefanie Rynders, Norman Julius Steinert, and Matteo Willeit
Earth Syst. Dynam., 15, 41–74, https://doi.org/10.5194/esd-15-41-2024, https://doi.org/10.5194/esd-15-41-2024, 2024
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This paper maps out the state-of-the-art literature on interactions between tipping elements relevant for current global warming pathways. We find indications that many of the interactions between tipping elements are destabilizing. This means that tipping cascades cannot be ruled out on centennial to millennial timescales at global warming levels between 1.5 and 2.0 °C or on shorter timescales if global warming surpasses 2.0 °C.
Anne Dallmeyer, Anneli Poska, Laurent Marquer, Andrea Seim, and Marie-José Gaillard
Clim. Past, 19, 1531–1557, https://doi.org/10.5194/cp-19-1531-2023, https://doi.org/10.5194/cp-19-1531-2023, 2023
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We compare past tree cover changes in Europe during the last 8000 years simulated with two dynamic global vegetation models and inferred from pollen data. The major model–data mismatch is related to the much earlier onset of anthropogenic deforestation in the data compared to the prescribed land use in the models. We show that land use, and not climate, is the main driver of the Holocene forest decline. The model–data agreement depends on the model tuning, challenging model–data comparisons.
Ulrike Herzschuh, Thomas Böhmer, Manuel Chevalier, Raphaël Hébert, Anne Dallmeyer, Chenzhi Li, Xianyong Cao, Odile Peyron, Larisa Nazarova, Elena Y. Novenko, Jungjae Park, Natalia A. Rudaya, Frank Schlütz, Lyudmila S. Shumilovskikh, Pavel E. Tarasov, Yongbo Wang, Ruilin Wen, Qinghai Xu, and Zhuo Zheng
Clim. Past, 19, 1481–1506, https://doi.org/10.5194/cp-19-1481-2023, https://doi.org/10.5194/cp-19-1481-2023, 2023
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A mismatch between model- and proxy-based Holocene climate change may partially originate from the poor spatial coverage of climate reconstructions. Here we investigate quantitative reconstructions of mean annual temperature and annual precipitation from 1908 pollen records in the Northern Hemisphere. Trends show strong latitudinal patterns and differ between (sub-)continents. Our work contributes to a better understanding of the global mean.
Zoé Rehder, Thomas Kleinen, Lars Kutzbach, Victor Stepanenko, Moritz Langer, and Victor Brovkin
Biogeosciences, 20, 2837–2855, https://doi.org/10.5194/bg-20-2837-2023, https://doi.org/10.5194/bg-20-2837-2023, 2023
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We use a new model to investigate how methane emissions from Arctic ponds change with warming. We find that emissions increase substantially. Under annual temperatures 5 °C above present temperatures, pond methane emissions are more than 3 times higher than now. Most of this increase is caused by an increase in plant productivity as plants provide the substrate microbes used to produce methane. We conclude that vegetation changes need to be included in predictions of pond methane emissions.
Ulrike Herzschuh, Thomas Böhmer, Chenzhi Li, Manuel Chevalier, Raphaël Hébert, Anne Dallmeyer, Xianyong Cao, Nancy H. Bigelow, Larisa Nazarova, Elena Y. Novenko, Jungjae Park, Odile Peyron, Natalia A. Rudaya, Frank Schlütz, Lyudmila S. Shumilovskikh, Pavel E. Tarasov, Yongbo Wang, Ruilin Wen, Qinghai Xu, and Zhuo Zheng
Earth Syst. Sci. Data, 15, 2235–2258, https://doi.org/10.5194/essd-15-2235-2023, https://doi.org/10.5194/essd-15-2235-2023, 2023
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Climate reconstruction from proxy data can help evaluate climate models. We present pollen-based reconstructions of mean July temperature, mean annual temperature, and annual precipitation from 2594 pollen records from the Northern Hemisphere, using three reconstruction methods (WA-PLS, WA-PLS_tailored, and MAT). Since no global or hemispheric synthesis of quantitative precipitation changes are available for the Holocene so far, this dataset will be of great value to the geoscientific community.
Thomas Kleinen, Sergey Gromov, Benedikt Steil, and Victor Brovkin
Clim. Past, 19, 1081–1099, https://doi.org/10.5194/cp-19-1081-2023, https://doi.org/10.5194/cp-19-1081-2023, 2023
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We modelled atmospheric methane continuously from the last glacial maximum to the present using a state-of-the-art Earth system model. Our model results compare well with reconstructions from ice cores and improve our understanding of a very intriguing period of Earth system history, the deglaciation, when atmospheric methane changed quickly and strongly. Deglacial methane changes are driven by emissions from tropical wetlands, with wetlands in high northern latitudes being secondary.
Manuel Chevalier, Anne Dallmeyer, Nils Weitzel, Chenzhi Li, Jean-Philippe Baudouin, Ulrike Herzschuh, Xianyong Cao, and Andreas Hense
Clim. Past, 19, 1043–1060, https://doi.org/10.5194/cp-19-1043-2023, https://doi.org/10.5194/cp-19-1043-2023, 2023
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Data–data and data–model vegetation comparisons are commonly based on comparing single vegetation estimates. While this approach generates good results on average, reducing pollen assemblages to single single plant functional type (PFT) or biome estimates can oversimplify the vegetation signal. We propose using a multivariate metric, the Earth mover's distance (EMD), to include more details about the vegetation structure when performing such comparisons.
Boris K. Biskaborn, Amy Forster, Gregor Pfalz, Lyudmila A. Pestryakova, Kathleen Stoof-Leichsenring, Jens Strauss, Tim Kröger, and Ulrike Herzschuh
Biogeosciences, 20, 1691–1712, https://doi.org/10.5194/bg-20-1691-2023, https://doi.org/10.5194/bg-20-1691-2023, 2023
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Lake sediment from the Russian Arctic was studied for microalgae and organic matter chemistry dated back to the last glacial 28 000 years. Species and chemistry responded to environmental changes such as the Younger Dryas cold event and the Holocene thermal maximum. Organic carbon accumulation correlated with rates of microalgae deposition only during warm episodes but not during the cold glacial.
Leonore Jungandreas, Cathy Hohenegger, and Martin Claussen
Clim. Past, 19, 637–664, https://doi.org/10.5194/cp-19-637-2023, https://doi.org/10.5194/cp-19-637-2023, 2023
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Increasing the vegetation cover over mid-Holcocene North Africa expands the West African monsoon ∼ 4–5° further north. This northward shift of monsoonal precipitation is caused by interactions of the land surface with large-scale monsoon circulation and the coupling of soil moisture to precipitation. We highlight the importance of considering not only how soil moisture influences precipitation but also how different precipitation characteristics alter the soil hydrology via runoff generation.
Furong Li, Marie-José Gaillard, Xianyong Cao, Ulrike Herzschuh, Shinya Sugita, Jian Ni, Yan Zhao, Chengbang An, Xiaozhong Huang, Yu Li, Hongyan Liu, Aizhi Sun, and Yifeng Yao
Earth Syst. Sci. Data, 15, 95–112, https://doi.org/10.5194/essd-15-95-2023, https://doi.org/10.5194/essd-15-95-2023, 2023
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The objective of this study is present the first gridded and temporally continuous quantitative plant-cover reconstruction for temperate and northern subtropical China over the last 12 millennia. The reconstructions are based on 94 pollen records and include estimates for 27 plant taxa, 10 plant functional types, and 3 land-cover types. The dataset is suitable for palaeoclimate modelling and the evaluation of simulated past vegetation cover and anthropogenic land-cover change from models.
Timon Miesner, Ulrike Herzschuh, Luidmila A. Pestryakova, Mareike Wieczorek, Evgenii S. Zakharov, Alexei I. Kolmogorov, Paraskovya V. Davydova, and Stefan Kruse
Earth Syst. Sci. Data, 14, 5695–5716, https://doi.org/10.5194/essd-14-5695-2022, https://doi.org/10.5194/essd-14-5695-2022, 2022
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We present data which were collected on expeditions to the northeast of the Russian Federation. One table describes the 226 locations we visited during those expeditions, and the other describes 40 289 trees which we recorded at these locations. We found out that important information on the forest cannot be predicted precisely from satellites. Thus, for anyone interested in distant forests, it is important to go to there and take measurements or use data (as presented here).
Femke van Geffen, Birgit Heim, Frederic Brieger, Rongwei Geng, Iuliia A. Shevtsova, Luise Schulte, Simone M. Stuenzi, Nadine Bernhardt, Elena I. Troeva, Luidmila A. Pestryakova, Evgenii S. Zakharov, Bringfried Pflug, Ulrike Herzschuh, and Stefan Kruse
Earth Syst. Sci. Data, 14, 4967–4994, https://doi.org/10.5194/essd-14-4967-2022, https://doi.org/10.5194/essd-14-4967-2022, 2022
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SiDroForest is an attempt to remedy data scarcity regarding vegetation data in the circumpolar region, whilst providing adjusted and labeled data for machine learning and upscaling practices. SiDroForest contains four datasets that include SfM point clouds, individually labeled trees, synthetic tree crowns and labeled Sentinel-2 patches that provide insights into the vegetation composition and forest structure of two important vegetation transition zones in Siberia, Russia.
Mateo Duque-Villegas, Martin Claussen, Victor Brovkin, and Thomas Kleinen
Clim. Past, 18, 1897–1914, https://doi.org/10.5194/cp-18-1897-2022, https://doi.org/10.5194/cp-18-1897-2022, 2022
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Using an Earth system model of intermediate complexity, we quantify contributions of the Earth's orbit, greenhouse gases (GHGs) and ice sheets to the strength of Saharan greening during late Quaternary African humid periods (AHPs). Orbital forcing is found as the dominant factor, having a critical threshold and accounting for most of the changes in the vegetation response. However, results suggest that GHGs may influence the orbital threshold and thus may play a pivotal role for future AHPs.
Ulrike Herzschuh, Chenzhi Li, Thomas Böhmer, Alexander K. Postl, Birgit Heim, Andrei A. Andreev, Xianyong Cao, Mareike Wieczorek, and Jian Ni
Earth Syst. Sci. Data, 14, 3213–3227, https://doi.org/10.5194/essd-14-3213-2022, https://doi.org/10.5194/essd-14-3213-2022, 2022
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Pollen preserved in environmental archives such as lake sediments and bogs are extensively used for reconstructions of past vegetation and climate. Here we present LegacyPollen 1.0, a dataset of 2831 fossil pollen records from all over the globe that were collected from publicly available databases. We harmonized the names of the pollen taxa so that all datasets can be jointly investigated. LegacyPollen 1.0 is available as an open-access dataset.
Ramesh Glückler, Rongwei Geng, Lennart Grimm, Izabella Baisheva, Ulrike Herzschuh, Kathleen R. Stoof-Leichsenring, Stefan Kruse, Andrei Andreev, Luidmila Pestryakova, and Elisabeth Dietze
EGUsphere, https://doi.org/10.5194/egusphere-2022-395, https://doi.org/10.5194/egusphere-2022-395, 2022
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Despite rapidly intensifying wildfire seasons in Siberian boreal forests, little is known about long-term relationships between changes in vegetation and shifts in wildfire activity. Using lake sediment proxies, we reconstruct such environmental changes over the past 10,800 years in Central Yakutia. We find that a more open forest may facilitate increased amounts of vegetation burning. The present-day dense larch forest might yet be mediating the current climate-driven wildfire intensification.
Nora Farina Specht, Martin Claussen, and Thomas Kleinen
Clim. Past, 18, 1035–1046, https://doi.org/10.5194/cp-18-1035-2022, https://doi.org/10.5194/cp-18-1035-2022, 2022
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Palaeoenvironmental records only provide a fragmentary picture of the lake and wetland extent in North Africa during the mid-Holocene. Therefore, we investigate the possible range of mid-Holocene precipitation changes caused by an estimated small and maximum lake extent and a maximum wetland extent. Results show a particularly strong monsoon precipitation response to lakes and wetlands over the Western Sahara and an increased monsoon precipitation when replacing lakes with vegetated wetlands.
Chenzhi Li, Alexander K. Postl, Thomas Böhmer, Xianyong Cao, Andrew M. Dolman, and Ulrike Herzschuh
Earth Syst. Sci. Data, 14, 1331–1343, https://doi.org/10.5194/essd-14-1331-2022, https://doi.org/10.5194/essd-14-1331-2022, 2022
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Here we present a global chronology framework of 2831 palynological records, including globally harmonized chronologies covering up to 273 000 years. A comparison with the original chronologies reveals a major improvement according to our assessment. Our chronology framework and revised chronologies will interest a broad geoscientific community, as it provides the opportunity to make use in synthesis studies of, for example, pollen-based vegetation and climate change.
Stefan Kruse, Simone M. Stuenzi, Julia Boike, Moritz Langer, Josias Gloy, and Ulrike Herzschuh
Geosci. Model Dev., 15, 2395–2422, https://doi.org/10.5194/gmd-15-2395-2022, https://doi.org/10.5194/gmd-15-2395-2022, 2022
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We coupled established models for boreal forest (LAVESI) and permafrost dynamics (CryoGrid) in Siberia to investigate interactions of the diverse vegetation layer with permafrost soils. Our tests showed improved active layer depth estimations and newly included species growth according to their species-specific limits. We conclude that the new model system can be applied to simulate boreal forest dynamics and transitions under global warming and disturbances, expanding our knowledge.
Jooyeop Lee, Martin Claussen, Jeongwon Kim, Je-Woo Hong, In-Sun Song, and Jinkyu Hong
Clim. Past, 18, 313–326, https://doi.org/10.5194/cp-18-313-2022, https://doi.org/10.5194/cp-18-313-2022, 2022
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It is still a challenge to simulate the so–called Green Sahara (GS), which was a wet and vegetative Sahara region in the mid–Holocene, using current climate models. Our analysis shows that Holocene greening is simulated better if the amount of soil nitrogen and soil texture is properly modified for the humid and vegetative GS period. Future climate simulation needs to consider consequent changes in soil nitrogen and texture with changes in vegetation cover for proper climate simulations.
Anne Dallmeyer, Martin Claussen, Stephan J. Lorenz, Michael Sigl, Matthew Toohey, and Ulrike Herzschuh
Clim. Past, 17, 2481–2513, https://doi.org/10.5194/cp-17-2481-2021, https://doi.org/10.5194/cp-17-2481-2021, 2021
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Using the comprehensive Earth system model, MPI-ESM1.2, we explore the global Holocene vegetation changes and interpret them in terms of the Holocene climate change. The model results reveal that most of the Holocene vegetation transitions seen outside the high northern latitudes can be attributed to modifications in the intensity of the global summer monsoons.
Stuart A. Vyse, Ulrike Herzschuh, Gregor Pfalz, Lyudmila A. Pestryakova, Bernhard Diekmann, Norbert Nowaczyk, and Boris K. Biskaborn
Biogeosciences, 18, 4791–4816, https://doi.org/10.5194/bg-18-4791-2021, https://doi.org/10.5194/bg-18-4791-2021, 2021
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Lakes act as important stores of organic carbon and inorganic sediment material. This study provides a first investigation into carbon and sediment accumulation and storage within an Arctic glacial lake from Far East Russia. It shows that major shifts are related to palaeoclimate variation that affects the development of the lake and its surrounding catchment. Spatial differences to other lake systems from other regions may reflect variability in processes controlled by latitude and altitude.
Leonore Jungandreas, Cathy Hohenegger, and Martin Claussen
Clim. Past, 17, 1665–1684, https://doi.org/10.5194/cp-17-1665-2021, https://doi.org/10.5194/cp-17-1665-2021, 2021
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We investigate the impact of explicitly resolving convection on the mid-Holocene West African Monsoon rain belt by employing the ICON climate model in high resolution. While the spatial distribution and intensity of the precipitation are improved by this technique, the monsoon extents further north and the mean summer rainfall is higher in the simulation with parameterized convection.
Ramesh Glückler, Ulrike Herzschuh, Stefan Kruse, Andrei Andreev, Stuart Andrew Vyse, Bettina Winkler, Boris K. Biskaborn, Luidmila Pestryakova, and Elisabeth Dietze
Biogeosciences, 18, 4185–4209, https://doi.org/10.5194/bg-18-4185-2021, https://doi.org/10.5194/bg-18-4185-2021, 2021
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Data about past fire activity are very sparse in Siberia. This study presents a first high-resolution record of charcoal particles from lake sediments in boreal eastern Siberia. It indicates that current levels of charcoal accumulation are not unprecedented. While a recent increase in reconstructed fire frequency coincides with rising temperatures and increasing human activity, vegetation composition does not seem to be a major driver behind changes in the fire regime in the past two millennia.
Lydia Stolpmann, Caroline Coch, Anne Morgenstern, Julia Boike, Michael Fritz, Ulrike Herzschuh, Kathleen Stoof-Leichsenring, Yury Dvornikov, Birgit Heim, Josefine Lenz, Amy Larsen, Katey Walter Anthony, Benjamin Jones, Karen Frey, and Guido Grosse
Biogeosciences, 18, 3917–3936, https://doi.org/10.5194/bg-18-3917-2021, https://doi.org/10.5194/bg-18-3917-2021, 2021
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Our new database summarizes DOC concentrations of 2167 water samples from 1833 lakes in permafrost regions across the Arctic to provide insights into linkages between DOC and environment. We found increasing lake DOC concentration with decreasing permafrost extent and higher DOC concentrations in boreal permafrost sites compared to tundra sites. Our study shows that DOC concentration depends on the environmental properties of a lake, especially permafrost extent, ecoregion, and vegetation.
Cited articles
Adam, M., Weitzel, N., and Rehfeld, K.: Identifying Global-Scale Patterns of Vegetation Change During the Last Deglaciation From Paleoclimate Networks, Palaeogeogr. Palaeocl., 36, e2021PA004265, https://doi.org/10.1029/2021PA004265, 2021.
Allen, J. R. M., Forrest, M., Hickler, T., Singarayer, J. S., Valdes, P. J., and Huntley, B.: Global vegetation patterns of the past 140,000 years, J. Biogeogr., 47, 2073–2090, https://doi.org/10.1111/jbi.13930, 2020.
Anhuf, D., Ledru, M.-P., Behling, H., Da Cruz, F. W., Cordeiro, R. C., Van der Hammen, T., Karmann, I., Marengo, J. A., De Oliveira, P. E., Pessenda, L., Siffedine, A., Albuquerque, A. L., and Da Silva Dias, P. L.: Paleo-environmental change in Amazonian and African rainforest during the LGM, Palaeogeogr. Palaeocl., 239, 510–527, https://doi.org/10.1016/j.palaeo.2006.01.017, 2006.
Annan, J. D., Hargreaves, J. C., and Mauritsen, T.: A new global surface temperature reconstruction for the Last Glacial Maximum, Clim. Past, 18, 1883–1896, https://doi.org/10.5194/cp-18-1883-2022, 2022.
Arora, V. K., Katavouta, A., Williams, R. G., Jones, C. D., Brovkin, V., Friedlingstein, P., Schwinger, J., Bopp, L., Boucher, O., Cadule, P., Chamberlain, M. A., Christian, J. R., Delire, C., Fisher, R. A., Hajima, T., Ilyina, T., Joetzjer, E., Kawamiya, M., Koven, C. D., Krasting, J. P., Law, R. M., Lawrence, D. M., Lenton, A., Lindsay, K., Pongratz, J., Raddatz, T., Séférian, R., Tachiiri, K., Tjiputra, J. F., Wiltshire, A., Wu, T., and Ziehn, T.: Carbon–concentration and carbon–climate feedbacks in CMIP6 models and their comparison to CMIP5 models, Biogeosciences, 17, 4173–4222, https://doi.org/10.5194/bg-17-4173-2020, 2020.
Bartlein, P. J., Harrison, S. P., Brewer, S., Connor, S., Davis, B. A. S., Gajewski, K., Guiot, J., Harrison-Prentice, T. I., Henderson, A., Peyron, O., Prentice, I. C., Scholze, M., Seppa, H., Shuman, B., Sugita, S., Thompson, R. S., Viau, A. E., Williams, J., and Wu, H.: Pollen-based continental climate reconstructions at 6 and 21 ka: a global synthesis, Clim. Dynam., 37, 775–802, https://doi.org/10.1007/s00382-010-0904-1, 2011.
Batchelor, C. L., Margold, M., Krapp, M., Murton, D. K., Dalton, A. S., Gibbard, P. L., Stokes, C. R., Murton, J. B., and Manica, A.: The configuration of Northern Hemisphere ice sheets through the Quaternary, Nat. Commun., 10, 3713, https://doi.org/10.1038/s41467-019-11601-2, 2019.
Berger, A. L.: Long-term variations of daily insolation and Quaternary climatic changes, Journal of Atmospheric Sciences, 35, 2361–2367, https://doi.org/10.1175/1520-0469(1978)035<2362:LTVODI>2.0.CO;2, 1978.
Beyer, R., Krapp, M., and Manica, A.: An empirical evaluation of bias correction methods for palaeoclimate simulations, Clim. Past, 16, 1493–1508, https://doi.org/10.5194/cp-16-1493-2020, 2020.
Bigelow, N. H., Brubaker, L. B., Edwards, M. E., Harrison, S. P., Prentice, I. C., Anderson, P. M., Andreev, A. A., Bartlein, P. J., Christensen, T. R., Cramer, W., Kaplan, J. O., Lozhkin, A. V., Matveyeva, N. V., Murray, D. F., McGuire, A. D., Razzhivin, V. Y., Ritchie, J. C., Smith, B., Walker, D. A., Gajewski, K., Wolf, V., Holmqvist, B. H., Igarashi, Y., Kremenetskii, K., Paus, A., Pisaric, M. F. J., and Volkova, V. S.: Climate change and Arctic ecosystems: 1. Vegetation changes north of 55° N between the last glacial maximum, mid-Holocene, and present, J. Geophys. Res.-Atmos., 108, https://doi.org/10.1029/2002jd002558, 2003.
Binney, H., Edwards, M., Macias-Fauria, M., Lozhkin, A., Anderson, P., Kaplan, J. O., Andreev, A., Bezrukova, E., Blyakharchuk, T., Jankovska, V., Khazina, I., Krivonogov, S., Kremenetski, K., Nield, J., Novenko, E., Ryabogina, N., Solovieva, N., Willis, K., and Zernitskaya, V.: Vegetation of Eurasia from the last glacial maximum to present: Key biogeographic patterns, Quaternary Sci. Rev., 157, 80–97, https://doi.org/10.1016/j.quascirev.2016.11.022, 2017.
Braconnot, P., Harrison, S. P., Kageyama, M., Bartlein, P. J., Masson-Delmotte, V., Abe-Ouchi, A., Otto-Bliesner, B., and Zhao, Y.: Evaluation of climate models using palaeoclimatic data, Nat. Clim. Change, 2, 417–424, https://doi.org/10.1038/NCLIMATE1456, 2012.
Cao, X., Tian, F., Li, F., Gaillard, M.-J., Rudaya, N., Xu, Q., and Herzschuh, U.: Pollen-based quantitative land-cover reconstruction for northern Asia covering the last 40 ka cal BP, Clim. Past, 15, 1503–1536, https://doi.org/10.5194/cp-15-1503-2019, 2019a.
Cao, X., Tian, F., Li, F., Gaillard, M.-J., Rudaya, N., Xu, Q., and Herzschuh, U.: Pollen-based quantitative land-cover reconstruction for northern Asia covering the last 40 ka cal BP, Clim. Past, 15, 1503–1536, https://doi.org/10.5194/cp-15-1503-2019, 2019b.
Charrier, G., Nolf, M., Leitinger, G., Charra-Vaskou, K., Losso, A., Tappeiner, U., Améglio, T., and Mayr, S.: Monitoring of Freezing Dynamics in Trees: A Simple Phase Shift Causes Complexity, Plant Physiol., 173, 2196–2207, https://doi.org/10.1104/pp.16.01815, 2017.
Cheng, J., Wu, H., Liu, Z., Gu, P., Wang, J., Zhao, C., Li, Q., Chen, H., Lu, H., Hu, H., Gao, Y., Yu, M., and Song, Y.: Vegetation feedback causes delayed ecosystem response to East Asian Summer Monsoon Rainfall during the Holocene, Nat. Commun., 12, 1–9, https://doi.org/10.1038/s41467-021-22087-2, 2021.
Clark, P. U., Shakun, J. D., Baker, P. A., Bartlein, P. J., Brewer, S., Brook, E., Carlson, A. E., Cheng, H., Kaufman, D. S., Liu, Z., Marchitto, T. M., Mix, A. C., Morrill, C., Otto-Bliesner, B. L., Pahnke, K., Russell, J. M., Whitlock, C., Adkins, J. F., Blois, J. L., Clark, J., Colman, S. M., Curry, W. B., Flower, B. P., He, F., Johnson, T. C., Lynch-Stieglitz, J., Markgraf, V., McManus, J., Mitrovica, J. X., Moreno, P. I., and Williams, J. W.: Global climate evolution during the last deglaciation, P. Natl. Acad. Sci. USA, 109, E1134–E1142, https://doi.org/10.1073/pnas.1116619109, 2012.
Claussen, M., Selent, K., Brovkin, V., Raddatz, T., and Gayler, V.: Impact of CO2 and climate on Last Glacial maximum vegetation – a factor separation, Biogeosciences, 10, 3593–3604, https://doi.org/10.5194/bg-10-3593-2013, 2013.
Dallmeyer, A.: From Ice Age to Present: Tree Cover Dynamics in REVEALS and MPI-ESM (Video), Edmond, V1 [video], https://doi.org/10.17617/3.O2GGHG, 2026.
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Short summary
We compare pollen-based reconstructions of Northern Hemisphere tree cover over the last 20 000 years with simulations from the Max-Planck-Institute Earth System Model (MPI-ESM). The model captures broad forest trends but misses key regional patterns and the mid-Holocene forest peak. Testing climate drivers reveals mismatches in how temperature, water, and CO2 control forests, pointing to structural limits and the need for improved vegetation processes in models.
We compare pollen-based reconstructions of Northern Hemisphere tree cover over the last 20 000...
