Articles | Volume 10, issue 6
https://doi.org/10.5194/bg-10-3593-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-10-3593-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
03 Jun 2013
Research article |
| 03 Jun 2013
Impact of CO2 and climate on Last Glacial maximum vegetation – a factor separation
M. Claussen
Max Planck Institute for Meteorology, Hamburg, Germany
K. Selent
Max Planck Institute for Meteorology, Hamburg, Germany
Meteorological Institute, University of Hamburg, Germany
now at: Deutsches Klimarechenzentrum DKRZ, Hamburg, Germany
V. Brovkin
Max Planck Institute for Meteorology, Hamburg, Germany
T. Raddatz
Max Planck Institute for Meteorology, Hamburg, Germany
V. Gayler
Max Planck Institute for Meteorology, Hamburg, Germany
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We simulate the last glacial cycle with a comprehensive Earth system model and investigate vegetation change in North Africa during the last four African humid periods (AHPs). We find a common AHP pattern of vegetation change and relate it to climatic factors to discuss how vegetation might have evolved in much older AHPs. The relationship we found for past AHPs does not hold for projected changes in North Africa under strong greenhouse gas warming.
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Biogeosciences, 15, 1947–1968, https://doi.org/10.5194/bg-15-1947-2018, https://doi.org/10.5194/bg-15-1947-2018, 2018
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T. Brücher, M. Claussen, and T. Raddatz
Earth Syst. Dynam., 6, 769–780, https://doi.org/10.5194/esd-6-769-2015, https://doi.org/10.5194/esd-6-769-2015, 2015
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V. P. Groner, M. Claussen, and C. Reick
Clim. Past, 11, 1361–1374, https://doi.org/10.5194/cp-11-1361-2015, https://doi.org/10.5194/cp-11-1361-2015, 2015
U. Port, M. Claussen, and V. Brovkin
Clim. Past Discuss., https://doi.org/10.5194/cpd-11-997-2015, https://doi.org/10.5194/cpd-11-997-2015, 2015
Revised manuscript not accepted
A. Dallmeyer, M. Claussen, N. Fischer, K. Haberkorn, S. Wagner, M. Pfeiffer, L. Jin, V. Khon, Y. Wang, and U. Herzschuh
Clim. Past, 11, 305–326, https://doi.org/10.5194/cp-11-305-2015, https://doi.org/10.5194/cp-11-305-2015, 2015
F. S. E. Vamborg, V. Brovkin, and M. Claussen
Earth Syst. Dynam., 5, 89–101, https://doi.org/10.5194/esd-5-89-2014, https://doi.org/10.5194/esd-5-89-2014, 2014
Yona Silvy, Thomas L. Frölicher, Jens Terhaar, Fortunat Joos, Friedrich A. Burger, Fabrice Lacroix, Myles Allen, Raffaele Bernardello, Laurent Bopp, Victor Brovkin, Jonathan R. Buzan, Patricia Cadule, Martin Dix, John Dunne, Pierre Friedlingstein, Goran Georgievski, Tomohiro Hajima, Stuart Jenkins, Michio Kawamiya, Nancy Y. Kiang, Vladimir Lapin, Donghyun Lee, Paul Lerner, Nadine Mengis, Estela A. Monteiro, David Paynter, Glen P. Peters, Anastasia Romanou, Jörg Schwinger, Sarah Sparrow, Eric Stofferahn, Jerry Tjiputra, Etienne Tourigny, and Tilo Ziehn
Earth Syst. Dynam., 15, 1591–1628, https://doi.org/10.5194/esd-15-1591-2024, https://doi.org/10.5194/esd-15-1591-2024, 2024
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The adaptive emission reduction approach is applied with Earth system models to generate temperature stabilization simulations. These simulations provide compatible emission pathways and budgets for a given warming level, uncovering uncertainty ranges previously missing in the Coupled Model Intercomparison Project scenarios. These target-based emission-driven simulations offer a more coherent assessment across models for studying both the carbon cycle and its impacts under climate stabilization.
Nathaelle Bouttes, Lester Kwiatkowski, Elodie Bougeot, Manon Berger, Victor Brovkin, and Guy Munhoven
EGUsphere, https://doi.org/10.5194/egusphere-2024-3738, https://doi.org/10.5194/egusphere-2024-3738, 2024
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Coral reefs are under threat due to warming and ocean acidification. It is difficult to project future coral reef production due to uncertainties in climate models, socio-economic scenarios and coral adaptation to warming. Here we have included a coral reef module within a climate model for the first time to evaluate the range of possible futures. We show that coral reef production decreases in most future scenarios, but in some cases coral reef carbonate production can persist.
Benjamin Mark Sanderson, Victor Brovkin, Rosie Fisher, David Hohn, Tatiana Ilyina, Chris Jones, Torben Koenigk, Charles Koven, Hongmei Li, David Lawrence, Peter Lawrence, Spencer Liddicoat, Andrew Macdougall, Nadine Mengis, Zebedee Nicholls, Eleanor O'Rourke, Anastasia Romanou, Marit Sandstad, Jörg Schwinger, Roland Seferian, Lori Sentman, Isla Simpson, Chris Smith, Norman Steinert, Abigail Swann, Jerry Tjiputra, and Tilo Ziehn
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Colin G. Jones, Fanny Adloff, Ben B. B. Booth, Peter M. Cox, Veronika Eyring, Pierre Friedlingstein, Katja Frieler, Helene T. Hewitt, Hazel A. Jeffery, Sylvie Joussaume, Torben Koenigk, Bryan N. Lawrence, Eleanor O'Rourke, Malcolm J. Roberts, Benjamin M. Sanderson, Roland Séférian, Samuel Somot, Pier Luigi Vidale, Detlef van Vuuren, Mario Acosta, Mats Bentsen, Raffaele Bernardello, Richard Betts, Ed Blockley, Julien Boé, Tom Bracegirdle, Pascale Braconnot, Victor Brovkin, Carlo Buontempo, Francisco Doblas-Reyes, Markus Donat, Italo Epicoco, Pete Falloon, Sandro Fiore, Thomas Frölicher, Neven S. Fučkar, Matthew J. Gidden, Helge F. Goessling, Rune Grand Graversen, Silvio Gualdi, José M. Gutiérrez, Tatiana Ilyina, Daniela Jacob, Chris D. Jones, Martin Juckes, Elizabeth Kendon, Erik Kjellström, Reto Knutti, Jason Lowe, Matthew Mizielinski, Paola Nassisi, Michael Obersteiner, Pierre Regnier, Romain Roehrig, David Salas y Mélia, Carl-Friedrich Schleussner, Michael Schulz, Enrico Scoccimarro, Laurent Terray, Hannes Thiemann, Richard A. Wood, Shuting Yang, and Sönke Zaehle
Earth Syst. Dynam., 15, 1319–1351, https://doi.org/10.5194/esd-15-1319-2024, https://doi.org/10.5194/esd-15-1319-2024, 2024
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Mateo Duque-Villegas, Martin Claussen, Thomas Kleinen, Jürgen Bader, and Christian H. Reick
Clim. Past Discuss., https://doi.org/10.5194/cp-2024-61, https://doi.org/10.5194/cp-2024-61, 2024
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Amali A. Amali, Clemens Schwingshackl, Akihiko Ito, Alina Barbu, Christine Delire, Daniele Peano, David M. Lawrence, David Wårlind, Eddy Robertson, Edouard L. Davin, Elena Shevliakova, Ian N. Harman, Nicolas Vuichard, Paul A. Miller, Peter J. Lawrence, Tilo Ziehn, Tomohiro Hajima, Victor Brovkin, Yanwu Zhang, Vivek K. Arora, and Julia Pongratz
EGUsphere, https://doi.org/10.5194/egusphere-2024-2460, https://doi.org/10.5194/egusphere-2024-2460, 2024
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Our study explored the impact of anthropogenic land-use change (LUC) on climate dynamics, focusing on biogeophysical (BGP) and biogeochemical (BGC) effects using data from the CMIP6-LUMIP project. We found that LUC-induced carbon emissions contribute to a BGC warming of 0.20 °C, with BGC effects dominating globally over BGP effects, which show regional variability. Our findings highlight discrepancies in model simulations and emphasise the need for improved representations of LUC processes.
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
Short summary
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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.
Tomohiro Hajima, Michio Kawamiya, Akihiko Ito, Kaoru Tachiiri, Chris Jones, Vivek Arora, Victor Brovkin, Roland Séférian, Spencer Liddicoat, Pierre Friedlingstein, and Elena Shevliakova
EGUsphere, https://doi.org/10.5194/egusphere-2024-188, https://doi.org/10.5194/egusphere-2024-188, 2024
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This study analyzes atmospheric CO2 concentrations and global carbon budgets simulated by multiple Earth system models, using several types of simulations. We successfully identified problems of global carbon budget in each model. We also found urgent issues that should be solved in the latest generation of models, land use change CO2 emissions.
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.
István Dunkl, Nicole Lovenduski, Alessio Collalti, Vivek K. Arora, Tatiana Ilyina, and Victor Brovkin
Biogeosciences, 20, 3523–3538, https://doi.org/10.5194/bg-20-3523-2023, https://doi.org/10.5194/bg-20-3523-2023, 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.
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In this paper we present the carbon cycle component of the newly developed fast Earth system model CLIMBER-X. The model can be run with interactive atmospheric CO2 to investigate the feedbacks between climate and the carbon cycle on temporal scales ranging from decades to > 100 000 years. CLIMBER-X is expected to be a useful tool for studying past climate–carbon cycle changes and for the investigation of the long-term future evolution of the Earth system.
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.
Philipp de Vrese, Goran Georgievski, Jesus Fidel Gonzalez Rouco, Dirk Notz, Tobias Stacke, Norman Julius Steinert, Stiig Wilkenskjeld, and Victor Brovkin
The Cryosphere, 17, 2095–2118, https://doi.org/10.5194/tc-17-2095-2023, https://doi.org/10.5194/tc-17-2095-2023, 2023
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The current generation of Earth system models exhibits large inter-model differences in the simulated climate of the Arctic and subarctic zone. We used an adapted version of the Max Planck Institute (MPI) Earth System Model to show that differences in the representation of the soil hydrology in permafrost-affected regions could help explain a large part of this inter-model spread and have pronounced impacts on important elements of Earth systems as far to the south as the tropics.
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.
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.
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.
Stiig Wilkenskjeld, Frederieke Miesner, Paul P. Overduin, Matteo Puglini, and Victor Brovkin
The Cryosphere, 16, 1057–1069, https://doi.org/10.5194/tc-16-1057-2022, https://doi.org/10.5194/tc-16-1057-2022, 2022
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Thawing permafrost releases carbon to the atmosphere, enhancing global warming. Part of the permafrost soils have been flooded by rising sea levels since the last ice age, becoming subsea permafrost (SSPF). The SSPF is less studied than the part on land. In this study we use a global model to obtain rates of thawing of SSPF under different future climate scenarios until the year 3000. After the year 2100 the scenarios strongly diverge, closely connected to the eventual disappearance of sea ice.
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.
István Dunkl, Aaron Spring, Pierre Friedlingstein, and Victor Brovkin
Earth Syst. Dynam., 12, 1413–1426, https://doi.org/10.5194/esd-12-1413-2021, https://doi.org/10.5194/esd-12-1413-2021, 2021
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The variability in atmospheric CO2 is largely controlled by terrestrial carbon fluxes. These land–atmosphere fluxes are predictable for around 2 years, but the mechanisms providing the predictability are not well understood. By decomposing the predictability of carbon fluxes into individual contributors we were able to explain the spatial and seasonal patterns and the interannual variability of CO2 flux predictability.
Aaron Spring, István Dunkl, Hongmei Li, Victor Brovkin, and Tatiana Ilyina
Earth Syst. Dynam., 12, 1139–1167, https://doi.org/10.5194/esd-12-1139-2021, https://doi.org/10.5194/esd-12-1139-2021, 2021
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Numerical carbon cycle prediction models usually do not start from observed carbon states due to sparse observations. Instead, only physical climate is reconstructed, assuming that the carbon cycle follows indirectly. Here, we test in an idealized framework how well this indirect and direct reconstruction with perfect observations works. We find that indirect reconstruction works quite well and that improvements from the direct method are limited, strengthening the current indirect use.
Alexander J. Winkler, Ranga B. Myneni, Alexis Hannart, Stephen Sitch, Vanessa Haverd, Danica Lombardozzi, Vivek K. Arora, Julia Pongratz, Julia E. M. S. Nabel, Daniel S. Goll, Etsushi Kato, Hanqin Tian, Almut Arneth, Pierre Friedlingstein, Atul K. Jain, Sönke Zaehle, and Victor Brovkin
Biogeosciences, 18, 4985–5010, https://doi.org/10.5194/bg-18-4985-2021, https://doi.org/10.5194/bg-18-4985-2021, 2021
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Satellite observations since the early 1980s show that Earth's greening trend is slowing down and that browning clusters have been emerging, especially in the last 2 decades. A collection of model simulations in conjunction with causal theory points at climatic changes as a key driver of vegetation changes in natural ecosystems. Most models underestimate the observed vegetation browning, especially in tropical rainforests, which could be due to an excessive CO2 fertilization effect in models.
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.
Philipp de Vrese, Tobias Stacke, Thomas Kleinen, and Victor Brovkin
The Cryosphere, 15, 1097–1130, https://doi.org/10.5194/tc-15-1097-2021, https://doi.org/10.5194/tc-15-1097-2021, 2021
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With large amounts of carbon stored in frozen soils and a highly energy-limited vegetation the Arctic is very sensitive to changes in climate. Here our simulations with the land surface model JSBACH reveal a number of offsetting factors moderating the Arctic's net response to global warming. More importantly we find that the effects of climate change may not be fully reversible on decadal timescales, leading to substantially different CH4 emissions depending on whether the Arctic warms or cools.
Claudia Tebaldi, Kevin Debeire, Veronika Eyring, Erich Fischer, John Fyfe, Pierre Friedlingstein, Reto Knutti, Jason Lowe, Brian O'Neill, Benjamin Sanderson, Detlef van Vuuren, Keywan Riahi, Malte Meinshausen, Zebedee Nicholls, Katarzyna B. Tokarska, George Hurtt, Elmar Kriegler, Jean-Francois Lamarque, Gerald Meehl, Richard Moss, Susanne E. Bauer, Olivier Boucher, Victor Brovkin, Young-Hwa Byun, Martin Dix, Silvio Gualdi, Huan Guo, Jasmin G. John, Slava Kharin, YoungHo Kim, Tsuyoshi Koshiro, Libin Ma, Dirk Olivié, Swapna Panickal, Fangli Qiao, Xinyao Rong, Nan Rosenbloom, Martin Schupfner, Roland Séférian, Alistair Sellar, Tido Semmler, Xiaoying Shi, Zhenya Song, Christian Steger, Ronald Stouffer, Neil Swart, Kaoru Tachiiri, Qi Tang, Hiroaki Tatebe, Aurore Voldoire, Evgeny Volodin, Klaus Wyser, Xiaoge Xin, Shuting Yang, Yongqiang Yu, and Tilo Ziehn
Earth Syst. Dynam., 12, 253–293, https://doi.org/10.5194/esd-12-253-2021, https://doi.org/10.5194/esd-12-253-2021, 2021
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We present an overview of CMIP6 ScenarioMIP outcomes from up to 38 participating ESMs according to the new SSP-based scenarios. Average temperature and precipitation projections according to a wide range of forcings, spanning a wider range than the CMIP5 projections, are documented as global averages and geographic patterns. Times of crossing various warming levels are computed, together with benefits of mitigation for selected pairs of scenarios. Comparisons with CMIP5 are also discussed.
Lena R. Boysen, Victor Brovkin, Julia Pongratz, David M. Lawrence, Peter Lawrence, Nicolas Vuichard, Philippe Peylin, Spencer Liddicoat, Tomohiro Hajima, Yanwu Zhang, Matthias Rocher, Christine Delire, Roland Séférian, Vivek K. Arora, Lars Nieradzik, Peter Anthoni, Wim Thiery, Marysa M. Laguë, Deborah Lawrence, and Min-Hui Lo
Biogeosciences, 17, 5615–5638, https://doi.org/10.5194/bg-17-5615-2020, https://doi.org/10.5194/bg-17-5615-2020, 2020
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We find a biogeophysically induced global cooling with strong carbon losses in a 20 million square kilometre idealized deforestation experiment performed by nine CMIP6 Earth system models. It takes many decades for the temperature signal to emerge, with non-local effects playing an important role. Despite a consistent experimental setup, models diverge substantially in their climate responses. This study offers unprecedented insights for understanding land use change effects in CMIP6 models.
Taraka Davies-Barnard, Johannes Meyerholt, Sönke Zaehle, Pierre Friedlingstein, Victor Brovkin, Yuanchao Fan, Rosie A. Fisher, Chris D. Jones, Hanna Lee, Daniele Peano, Benjamin Smith, David Wårlind, and Andy J. Wiltshire
Biogeosciences, 17, 5129–5148, https://doi.org/10.5194/bg-17-5129-2020, https://doi.org/10.5194/bg-17-5129-2020, 2020
Vivek K. Arora, Anna Katavouta, Richard G. Williams, Chris D. Jones, Victor Brovkin, Pierre Friedlingstein, Jörg Schwinger, Laurent Bopp, Olivier Boucher, Patricia Cadule, Matthew A. Chamberlain, James R. Christian, Christine Delire, Rosie A. Fisher, Tomohiro Hajima, Tatiana Ilyina, Emilie Joetzjer, Michio Kawamiya, Charles D. Koven, John P. Krasting, Rachel M. Law, David M. Lawrence, Andrew Lenton, Keith Lindsay, Julia Pongratz, Thomas Raddatz, Roland Séférian, Kaoru Tachiiri, Jerry F. Tjiputra, Andy Wiltshire, Tongwen Wu, and Tilo Ziehn
Biogeosciences, 17, 4173–4222, https://doi.org/10.5194/bg-17-4173-2020, https://doi.org/10.5194/bg-17-4173-2020, 2020
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Since the preindustrial period, land and ocean have taken up about half of the carbon emitted into the atmosphere by humans. Comparison of different earth system models with the carbon cycle allows us to assess how carbon uptake by land and ocean differs among models. This yields an estimate of uncertainty in our understanding of how land and ocean respond to increasing atmospheric CO2. This paper summarizes results from two such model intercomparison projects that use an idealized scenario.
Matteo Puglini, Victor Brovkin, Pierre Regnier, and Sandra Arndt
Biogeosciences, 17, 3247–3275, https://doi.org/10.5194/bg-17-3247-2020, https://doi.org/10.5194/bg-17-3247-2020, 2020
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A reaction-transport model to assess the potential non-turbulent methane flux from the East Siberian Arctic sediments to water columns is applied here. We show that anaerobic oxidation of methane (AOM) is an efficient filter except for high values of sedimentation rate and advective flow, which enable considerable non-turbulent steady-state methane fluxes. Significant transient methane fluxes can also occur during the building-up phase of the AOM-performing biomass microbial community.
Andrew H. MacDougall, Thomas L. Frölicher, Chris D. Jones, Joeri Rogelj, H. Damon Matthews, Kirsten Zickfeld, Vivek K. Arora, Noah J. Barrett, Victor Brovkin, Friedrich A. Burger, Micheal Eby, Alexey V. Eliseev, Tomohiro Hajima, Philip B. Holden, Aurich Jeltsch-Thömmes, Charles Koven, Nadine Mengis, Laurie Menviel, Martine Michou, Igor I. Mokhov, Akira Oka, Jörg Schwinger, Roland Séférian, Gary Shaffer, Andrei Sokolov, Kaoru Tachiiri, Jerry Tjiputra, Andrew Wiltshire, and Tilo Ziehn
Biogeosciences, 17, 2987–3016, https://doi.org/10.5194/bg-17-2987-2020, https://doi.org/10.5194/bg-17-2987-2020, 2020
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The Zero Emissions Commitment (ZEC) is the change in global temperature expected to occur following the complete cessation of CO2 emissions. Here we use 18 climate models to assess the value of ZEC. For our experiment we find that ZEC 50 years after emissions cease is between −0.36 to +0.29 °C. The most likely value of ZEC is assessed to be close to zero. However, substantial continued warming for decades or centuries following cessation of CO2 emission cannot be ruled out.
Thomas Kleinen, Uwe Mikolajewicz, and Victor Brovkin
Clim. Past, 16, 575–595, https://doi.org/10.5194/cp-16-575-2020, https://doi.org/10.5194/cp-16-575-2020, 2020
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We investigate the changes in natural methane emissions between the Last Glacial Maximum and preindustrial periods with a methane-enabled version of MPI-ESM. We consider all natural sources of methane except for emissions from wild animals and geological sources. Changes are dominated by changes in tropical wetland emissions, high-latitude wetlands play a secondary role, and all other natural sources are of minor importance. We explain the changes in ice core methane by methane emissions only.
Anne Dallmeyer, Martin Claussen, Stephan J. Lorenz, and Timothy Shanahan
Clim. Past, 16, 117–140, https://doi.org/10.5194/cp-16-117-2020, https://doi.org/10.5194/cp-16-117-2020, 2020
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We analyse the end of the African humid period (AHP) in a transient Holocene simulation performed with the comprehensive Earth system model MPI-ESM1.2. The model reproduces the time-transgressive end of the AHP evident in proxy data and indicates that changes in moisture can be attributed to the retreat of the summer monsoon and to changes in the extratropical troughs. The spatially varying impact of these systems imposes regionally different responses to the Holocene insolation change.
Georgii A. Alexandrov, Victor A. Brovkin, Thomas Kleinen, and Zicheng Yu
Biogeosciences, 17, 47–54, https://doi.org/10.5194/bg-17-47-2020, https://doi.org/10.5194/bg-17-47-2020, 2020
Alexander J. Winkler, Ranga B. Myneni, and Victor Brovkin
Earth Syst. Dynam., 10, 501–523, https://doi.org/10.5194/esd-10-501-2019, https://doi.org/10.5194/esd-10-501-2019, 2019
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The concept of
emergent constraintsis a key method to reduce uncertainty in multi-model climate projections using historical simulations and observations. Here, we present an in-depth analysis of the applicability of the method and uncover possible limitations. Key limitations are a lack of comparability (temporal, spatial, and conceptual) between models and observations and the disagreement between models on system dynamics throughout different levels of atmospheric CO2 concentration.
Victor Brovkin, Stephan Lorenz, Thomas Raddatz, Tatiana Ilyina, Irene Stemmler, Matthew Toohey, and Martin Claussen
Biogeosciences, 16, 2543–2555, https://doi.org/10.5194/bg-16-2543-2019, https://doi.org/10.5194/bg-16-2543-2019, 2019
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Mechanisms of atmospheric CO2 growth by 20 ppm from 6000 BCE to the pre-industrial period are still uncertain. We apply the Earth system model MPI-ESM-LR for two transient simulations of the climate–carbon cycle. An additional process, e.g. carbonate accumulation on shelves, is required for consistency with ice-core CO2 data. Our simulations support the hypothesis that the ocean was a source of CO2 until the late Holocene when anthropogenic CO2 sources started to affect atmospheric CO2.
Anne Dallmeyer, Martin Claussen, and Victor Brovkin
Clim. Past, 15, 335–366, https://doi.org/10.5194/cp-15-335-2019, https://doi.org/10.5194/cp-15-335-2019, 2019
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A simple but powerful method for the biomisation of plant functional type distributions is introduced and tested for six different dynamic global vegetation models based on pre-industrial and palaeo-simulations. The method facilitates the direct comparison between vegetation distributions simulated by different Earth system models and between model results and the pollen-based biome reconstructions. It is therefore a powerful tool for the evaluation of Earth system models.
Thomas Schneider von Deimling, Thomas Kleinen, Gustaf Hugelius, Christian Knoblauch, Christian Beer, and Victor Brovkin
Clim. Past, 14, 2011–2036, https://doi.org/10.5194/cp-14-2011-2018, https://doi.org/10.5194/cp-14-2011-2018, 2018
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Past cold ice age temperatures and the subsequent warming towards the Holocene had large consequences for soil organic carbon (SOC) stored in perennially frozen grounds. Using an Earth system model we show how the spread in areas affected by permafrost have changed under deglacial warming, along with changes in SOC accumulation. Our model simulations suggest phases of circum-Arctic permafrost SOC gain and losses, with a net increase in SOC between the last glacial maximum and the pre-industrial.
Thomas Riddick, Victor Brovkin, Stefan Hagemann, and Uwe Mikolajewicz
Geosci. Model Dev., 11, 4291–4316, https://doi.org/10.5194/gmd-11-4291-2018, https://doi.org/10.5194/gmd-11-4291-2018, 2018
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During the Last Glacial Maximum, many rivers were blocked by the presence of large ice sheets and thus found new routes to the sea. This resulted in changes in the pattern of freshwater discharge into the oceans and thus would have significantly affected ocean circulation. Also, rivers found routes across the vast exposed continental shelves to the lower coastlines of that time. We propose a model for such changes in river routing suitable for use in wider models of the last glacial cycle.
Uwe Mikolajewicz, Florian Ziemen, Guido Cioni, Martin Claussen, Klaus Fraedrich, Marvin Heidkamp, Cathy Hohenegger, Diego Jimenez de la Cuesta, Marie-Luise Kapsch, Alexander Lemburg, Thorsten Mauritsen, Katharina Meraner, Niklas Röber, Hauke Schmidt, Katharina D. Six, Irene Stemmler, Talia Tamarin-Brodsky, Alexander Winkler, Xiuhua Zhu, and Bjorn Stevens
Earth Syst. Dynam., 9, 1191–1215, https://doi.org/10.5194/esd-9-1191-2018, https://doi.org/10.5194/esd-9-1191-2018, 2018
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Model experiments show that changing the sense of Earth's rotation has relatively little impact on the globally and zonally averaged energy budgets but leads to large shifts in continental climates and patterns of precipitation. The retrograde world is greener as the desert area shrinks. Deep water formation shifts from the North Atlantic to the North Pacific with subsequent changes in ocean overturning. Over large areas of the Indian Ocean, cyanobacteria dominate over bulk phytoplankton.
Sabine Egerer, Martin Claussen, and Christian Reick
Clim. Past, 14, 1051–1066, https://doi.org/10.5194/cp-14-1051-2018, https://doi.org/10.5194/cp-14-1051-2018, 2018
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We find a rapid increase in simulated dust deposition between 6 and
4 ka BP that is fairly consistent with an abrupt change in dust deposition that was observed in marine sediment records at around 5 ka BP. This rapid change is caused by a rapid increase in simulated dust emissions in the western Sahara due to a fast decline in vegetation cover and a locally strong reduction of lake area. Our study identifies spatial and temporal heterogeneity in the transition of the North African landscape.
Sirisha Kalidindi, Christian H. Reick, Thomas Raddatz, and Martin Claussen
Earth Syst. Dynam., 9, 739–756, https://doi.org/10.5194/esd-9-739-2018, https://doi.org/10.5194/esd-9-739-2018, 2018
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Using climate simulations, we investigate the role of water recycling in shaping the climate of low-obliquity Earth-like terra-planets. By such a mechanism feeding water back from the extra-tropics to the tropics, the planet can assume two drastically different climate states differing by more than 35 K in global temperature. We describe the bifurcation between the two states occurring upon changes in surface albedo and argue that the bistability hints at a wider habitable zone for such planets.
Sandy P. Harrison, Patrick J. Bartlein, Victor Brovkin, Sander Houweling, Silvia Kloster, and I. Colin Prentice
Earth Syst. Dynam., 9, 663–677, https://doi.org/10.5194/esd-9-663-2018, https://doi.org/10.5194/esd-9-663-2018, 2018
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Temperature affects fire occurrence and severity. Warming will increase fire-related carbon emissions and thus atmospheric CO2. The size of this feedback is not known. We use charcoal records to estimate pre-industrial fire emissions and a simple land–biosphere model to quantify the feedback. We infer a feedback strength of 5.6 3.2 ppm CO2 per degree of warming and a gain of 0.09 ± 0.05 for a climate sensitivity of 2.8 K. Thus, fire feedback is a large part of the climate–carbon-cycle feedback.
Markus Adloff, Christian H. Reick, and Martin Claussen
Earth Syst. Dynam., 9, 413–425, https://doi.org/10.5194/esd-9-413-2018, https://doi.org/10.5194/esd-9-413-2018, 2018
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Computer simulations show that during an ice age a strong atmospheric CO2 increase would have resulted in stronger carbon uptake of the continents than today. Causes are the larger potential of glacial vegetation to increase its photosynthetic efficiency under increasing CO2 and the smaller amount of carbon in extratropical soils during an ice age that can be released under greenhouse warming. Hence, for different climates the Earth system is differently sensitive to carbon cycle perturbations.
Vivienne P. Groner, Thomas Raddatz, Christian H. Reick, and Martin Claussen
Biogeosciences, 15, 1947–1968, https://doi.org/10.5194/bg-15-1947-2018, https://doi.org/10.5194/bg-15-1947-2018, 2018
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We show that plant functional diversity significantly affects climate–vegetation interaction and the climate–vegetation system stability in response to external forcing using a series of coupled land–atmosphere simulation. Our findings raise the question of how realistically Earth system models can actually represent climate–vegetation interaction, considering the incomplete representation of plant functional diversity in the current generation of land surface models.
Maarit Raivonen, Sampo Smolander, Leif Backman, Jouni Susiluoto, Tuula Aalto, Tiina Markkanen, Jarmo Mäkelä, Janne Rinne, Olli Peltola, Mika Aurela, Annalea Lohila, Marin Tomasic, Xuefei Li, Tuula Larmola, Sari Juutinen, Eeva-Stiina Tuittila, Martin Heimann, Sanna Sevanto, Thomas Kleinen, Victor Brovkin, and Timo Vesala
Geosci. Model Dev., 10, 4665–4691, https://doi.org/10.5194/gmd-10-4665-2017, https://doi.org/10.5194/gmd-10-4665-2017, 2017
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Wetlands are one of the most significant natural sources of the strong greenhouse gas methane. We developed a model that can be used within a larger wetland carbon model to simulate the methane emissions. In this study, we present the model and results of its testing. We found that the model works well with different settings and that the results depend primarily on the rate of input anoxic soil respiration and also on factors that affect the simulated oxygen concentrations in the wetland soil.
Andrey Ganopolski and Victor Brovkin
Clim. Past, 13, 1695–1716, https://doi.org/10.5194/cp-13-1695-2017, https://doi.org/10.5194/cp-13-1695-2017, 2017
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Ice cores reveal that atmospheric CO2 concentration varied synchronously with the global ice volume. Explaining the mechanism of glacial–interglacial variations of atmospheric CO2 concentrations and the link between CO2 and ice sheets evolution still remains a challenge. Here using the Earth system model of intermediate complexity we performed for the first time simulations of co-evolution of climate, ice sheets and carbon cycle using the astronomical forcing as the only external forcing.
Daniel S. Goll, Alexander J. Winkler, Thomas Raddatz, Ning Dong, Ian Colin Prentice, Philippe Ciais, and Victor Brovkin
Geosci. Model Dev., 10, 2009–2030, https://doi.org/10.5194/gmd-10-2009-2017, https://doi.org/10.5194/gmd-10-2009-2017, 2017
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The response of soil organic carbon decomposition to warming and the interactions between nitrogen and carbon cycling affect the feedbacks between the land carbon cycle and the climate. In the model JSBACH carbon–nitrogen interactions have only a small effect on the feedbacks, whereas modifications of soil organic carbon decomposition have a large effect. The carbon cycle in the improved model is more resilient to climatic changes than in previous version of the model.
Anne Dallmeyer, Martin Claussen, Jian Ni, Xianyong Cao, Yongbo Wang, Nils Fischer, Madlene Pfeiffer, Liya Jin, Vyacheslav Khon, Sebastian Wagner, Kerstin Haberkorn, and Ulrike Herzschuh
Clim. Past, 13, 107–134, https://doi.org/10.5194/cp-13-107-2017, https://doi.org/10.5194/cp-13-107-2017, 2017
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The vegetation distribution in eastern Asia is supposed to be very sensitive to climate change. Since proxy records are scarce, hitherto a mechanistic understanding of the past spatio-temporal climate–vegetation relationship is lacking. To assess the Holocene vegetation change, we forced the diagnostic biome model BIOME4 with climate anomalies of different transient climate simulations.
Beniamino Abis and Victor Brovkin
Biogeosciences, 14, 511–527, https://doi.org/10.5194/bg-14-511-2017, https://doi.org/10.5194/bg-14-511-2017, 2017
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We study the link between the boreal tree-cover fraction distribution and eight globally observed environmental factors. We find that they exert a strong control over the tree-cover distribution, generally uniquely determining its state. Furthermore, we show the location of areas with potentially alternative tree-cover states under the same environmental conditions. These areas represent transition zones with reduced resilience, where the forest can shift between different vegetation states.
Marielle Saunois, Philippe Bousquet, Ben Poulter, Anna Peregon, Philippe Ciais, Josep G. Canadell, Edward J. Dlugokencky, Giuseppe Etiope, David Bastviken, Sander Houweling, Greet Janssens-Maenhout, Francesco N. Tubiello, Simona Castaldi, Robert B. Jackson, Mihai Alexe, Vivek K. Arora, David J. Beerling, Peter Bergamaschi, Donald R. Blake, Gordon Brailsford, Victor Brovkin, Lori Bruhwiler, Cyril Crevoisier, Patrick Crill, Kristofer Covey, Charles Curry, Christian Frankenberg, Nicola Gedney, Lena Höglund-Isaksson, Misa Ishizawa, Akihiko Ito, Fortunat Joos, Heon-Sook Kim, Thomas Kleinen, Paul Krummel, Jean-François Lamarque, Ray Langenfelds, Robin Locatelli, Toshinobu Machida, Shamil Maksyutov, Kyle C. McDonald, Julia Marshall, Joe R. Melton, Isamu Morino, Vaishali Naik, Simon O'Doherty, Frans-Jan W. Parmentier, Prabir K. Patra, Changhui Peng, Shushi Peng, Glen P. Peters, Isabelle Pison, Catherine Prigent, Ronald Prinn, Michel Ramonet, William J. Riley, Makoto Saito, Monia Santini, Ronny Schroeder, Isobel J. Simpson, Renato Spahni, Paul Steele, Atsushi Takizawa, Brett F. Thornton, Hanqin Tian, Yasunori Tohjima, Nicolas Viovy, Apostolos Voulgarakis, Michiel van Weele, Guido R. van der Werf, Ray Weiss, Christine Wiedinmyer, David J. Wilton, Andy Wiltshire, Doug Worthy, Debra Wunch, Xiyan Xu, Yukio Yoshida, Bowen Zhang, Zhen Zhang, and Qiuan Zhu
Earth Syst. Sci. Data, 8, 697–751, https://doi.org/10.5194/essd-8-697-2016, https://doi.org/10.5194/essd-8-697-2016, 2016
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An accurate assessment of the methane budget is important to understand the atmospheric methane concentrations and trends and to provide realistic pathways for climate change mitigation. The various and diffuse sources of methane as well and its oxidation by a very short lifetime radical challenge this assessment. We quantify the methane sources and sinks as well as their uncertainties based on both bottom-up and top-down approaches provided by a broad international scientific community.
Thomas Kleinen, Victor Brovkin, and Guy Munhoven
Clim. Past, 12, 2145–2160, https://doi.org/10.5194/cp-12-2145-2016, https://doi.org/10.5194/cp-12-2145-2016, 2016
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We investigate trends in atmospheric CO2 during three recent interglacials – the Holocene, the Eemian and MIS 11 – using an earth system model of intermediate complexity. Our model experiments show a considerable improvement in the modelled CO2 trends for all three interglacials if peat accumulation and shallow water CaCO3 sedimentation are included, forcing the model only with orbital and sea level changes. The Holocene CO2 trend requires anthropogenic emissions of CO2 only after 3 ka BP.
Sylvia S. Nyawira, Julia E. M. S. Nabel, Axel Don, Victor Brovkin, and Julia Pongratz
Biogeosciences, 13, 5661–5675, https://doi.org/10.5194/bg-13-5661-2016, https://doi.org/10.5194/bg-13-5661-2016, 2016
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We introduce an approach applicable to dynamic global vegetation models for evaluating simulated soil carbon changes from land-use changes against meta-analyses. The approach makes use of the large spatial coverage of the observations, and accounts for different ages of the sampled land-use transitions. The evaluation offers an opportunity for identifying causes of model–data discrepancies. Applied to the model JSBACH, we find that introducing crop harvest substantially improves the results.
Ana Bastos, Philippe Ciais, Jonathan Barichivich, Laurent Bopp, Victor Brovkin, Thomas Gasser, Shushi Peng, Julia Pongratz, Nicolas Viovy, and Cathy M. Trudinger
Biogeosciences, 13, 4877–4897, https://doi.org/10.5194/bg-13-4877-2016, https://doi.org/10.5194/bg-13-4877-2016, 2016
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The ice-core record shows a stabilisation of atmospheric CO2 in the 1940s, despite continued emissions from fossil fuel burning and land-use change (LUC). We use up-to-date reconstructions of the CO2 sources and sinks over the 20th century to evaluate whether these capture the CO2 plateau and to test the previously proposed hypothesis. Both strong terrestrial sink, possibly due to LUC not fully accounted for in the records, and enhanced oceanic uptake are necessary to explain this stall.
David M. Lawrence, George C. Hurtt, Almut Arneth, Victor Brovkin, Kate V. Calvin, Andrew D. Jones, Chris D. Jones, Peter J. Lawrence, Nathalie de Noblet-Ducoudré, Julia Pongratz, Sonia I. Seneviratne, and Elena Shevliakova
Geosci. Model Dev., 9, 2973–2998, https://doi.org/10.5194/gmd-9-2973-2016, https://doi.org/10.5194/gmd-9-2973-2016, 2016
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Human land-use activities have resulted in large changes to the Earth's surface, with resulting implications for climate. In the future, land-use activities are likely to expand and intensify further to meet growing demands for food, fiber, and energy. The goal of LUMIP is to take the next steps in land-use change science, and enable, coordinate, and ultimately address the most important land-use science questions in more depth and sophistication than possible in a multi-model context to date.
Chris D. Jones, Vivek Arora, Pierre Friedlingstein, Laurent Bopp, Victor Brovkin, John Dunne, Heather Graven, Forrest Hoffman, Tatiana Ilyina, Jasmin G. John, Martin Jung, Michio Kawamiya, Charlie Koven, Julia Pongratz, Thomas Raddatz, James T. Randerson, and Sönke Zaehle
Geosci. Model Dev., 9, 2853–2880, https://doi.org/10.5194/gmd-9-2853-2016, https://doi.org/10.5194/gmd-9-2853-2016, 2016
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How the carbon cycle interacts with climate will affect future climate change and how society plans emissions reductions to achieve climate targets. The Coupled Climate Carbon Cycle Model Intercomparison Project (C4MIP) is an endorsed activity of CMIP6 and aims to quantify these interactions and feedbacks in state-of-the-art climate models. This paper lays out the experimental protocol for modelling groups to follow to contribute to C4MIP. It is a contribution to the CMIP6 GMD Special Issue.
Alexander Lemburg, Martin Claussen, and Felix Ament
Clim. Past Discuss., https://doi.org/10.5194/cp-2016-68, https://doi.org/10.5194/cp-2016-68, 2016
Manuscript not accepted for further review
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The deforestation of Easter Island several hundred years ago might have influenced its local near-surface climate. With a series of numerical model experiments we investigate the impact of deforestation on precipitation and near-surface climate. We find that a deforested Easter Island appears to be significantly less resistant to drought than a forested island and thus, deforestation has probably exacerbated the effects of past climate drought spells on Easter Island's socio-ecological systems.
Ulrike Port, Martin Claussen, and Victor Brovkin
Earth Syst. Dynam., 7, 535–547, https://doi.org/10.5194/esd-7-535-2016, https://doi.org/10.5194/esd-7-535-2016, 2016
Sabine Egerer, Martin Claussen, Christian Reick, and Tanja Stanelle
Clim. Past, 12, 1009–1027, https://doi.org/10.5194/cp-12-1009-2016, https://doi.org/10.5194/cp-12-1009-2016, 2016
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We demonstrate for the first time the direct link between dust accumulation in marine sediment cores and Saharan land surface by simulating the mid-Holocene and pre-industrial dust cycle as a function of Saharan land surface cover and atmosphere-ocean conditions using the coupled atmosphere-aerosol model ECHAM6-HAM2.1. Mid-Holocene surface characteristics, including vegetation cover and lake surface area, are derived from proxy data and simulations.
Fabio Cresto Aleina, Benjamin R. K. Runkle, Tim Brücher, Thomas Kleinen, and Victor Brovkin
Geosci. Model Dev., 9, 915–926, https://doi.org/10.5194/gmd-9-915-2016, https://doi.org/10.5194/gmd-9-915-2016, 2016
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This study presents the hotspot parameterization, a novel approach to upscaling methane emissions in a boreal peatland from the micro-topographic scale to the landscape scale. We based this new parameterization on the analysis of water table patterns generated by the Hummock–Hollow (HH) model. We show how the hotspot parameterization successfully upscales the micro-topographic controls on methane emissions for both present-day conditions and for the next century under three different scenarios.
T. Brücher, M. Claussen, and T. Raddatz
Earth Syst. Dynam., 6, 769–780, https://doi.org/10.5194/esd-6-769-2015, https://doi.org/10.5194/esd-6-769-2015, 2015
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A major link between climate and humans in northern Africa, and the Sahel in particular, is land use. We assess possible feedbacks between the type of land use and harvest intensity and climate by analysing a series of idealized GCM experiments using the MPI-ESM. Our study suggests marginal feedback between land use changes and climate changes triggered by strong greenhouse gas emissions.
U. Port and M. Claussen
Clim. Past, 11, 1563–1574, https://doi.org/10.5194/cp-11-1563-2015, https://doi.org/10.5194/cp-11-1563-2015, 2015
V. P. Groner, M. Claussen, and C. Reick
Clim. Past, 11, 1361–1374, https://doi.org/10.5194/cp-11-1361-2015, https://doi.org/10.5194/cp-11-1361-2015, 2015
F. Cresto Aleina, B. R. K. Runkle, T. Kleinen, L. Kutzbach, J. Schneider, and V. Brovkin
Biogeosciences, 12, 5689–5704, https://doi.org/10.5194/bg-12-5689-2015, https://doi.org/10.5194/bg-12-5689-2015, 2015
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We developed a process-based model for peatland micro-topography and hydrology, the Hummock-Hollow (HH) model, which explicitly represents small-scale surface elevation changes. By coupling the HH model with a model for soil methane processes, we are able to model the effects of micro-topography on hydrology and methane emissions in a typical boreal peatland. We also identify potential biases that models without a micro-topographic representation can introduce in large-scale models.
C. D. Koven, J. Q. Chambers, K. Georgiou, R. Knox, R. Negron-Juarez, W. J. Riley, V. K. Arora, V. Brovkin, P. Friedlingstein, and C. D. Jones
Biogeosciences, 12, 5211–5228, https://doi.org/10.5194/bg-12-5211-2015, https://doi.org/10.5194/bg-12-5211-2015, 2015
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Terrestrial carbon feedbacks are a large uncertainty in climate change. We separate modeled feedback responses into those governed by changed carbon inputs (productivity) and changed outputs (turnover). The disaggregated responses show that both are important in controlling inter-model uncertainty. Interactions between productivity and turnover are also important, and research must focus on these interactions for more accurate projections of carbon cycle feedbacks.
T. J. Bohn, J. R. Melton, A. Ito, T. Kleinen, R. Spahni, B. D. Stocker, B. Zhang, X. Zhu, R. Schroeder, M. V. Glagolev, S. Maksyutov, V. Brovkin, G. Chen, S. N. Denisov, A. V. Eliseev, A. Gallego-Sala, K. C. McDonald, M.A. Rawlins, W. J. Riley, Z. M. Subin, H. Tian, Q. Zhuang, and J. O. Kaplan
Biogeosciences, 12, 3321–3349, https://doi.org/10.5194/bg-12-3321-2015, https://doi.org/10.5194/bg-12-3321-2015, 2015
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We evaluated 21 forward models and 5 inversions over western Siberia in terms of CH4 emissions and simulated wetland areas and compared these results to an intensive in situ CH4 flux data set, several wetland maps, and two satellite inundation products. In addition to assembling a definitive collection of methane emissions estimates for the region, we were able to identify the types of wetland maps and model features necessary for accurate simulations of high-latitude wetlands.
S. Kloster, T. Brücher, V. Brovkin, and S. Wilkenskjeld
Clim. Past, 11, 781–788, https://doi.org/10.5194/cp-11-781-2015, https://doi.org/10.5194/cp-11-781-2015, 2015
U. Port, M. Claussen, and V. Brovkin
Clim. Past Discuss., https://doi.org/10.5194/cpd-11-997-2015, https://doi.org/10.5194/cpd-11-997-2015, 2015
Revised manuscript not accepted
A. Dallmeyer, M. Claussen, N. Fischer, K. Haberkorn, S. Wagner, M. Pfeiffer, L. Jin, V. Khon, Y. Wang, and U. Herzschuh
Clim. Past, 11, 305–326, https://doi.org/10.5194/cp-11-305-2015, https://doi.org/10.5194/cp-11-305-2015, 2015
F. S. E. Vamborg, V. Brovkin, and M. Claussen
Earth Syst. Dynam., 5, 89–101, https://doi.org/10.5194/esd-5-89-2014, https://doi.org/10.5194/esd-5-89-2014, 2014
P. Dass, C. Müller, V. Brovkin, and W. Cramer
Earth Syst. Dynam., 4, 409–424, https://doi.org/10.5194/esd-4-409-2013, https://doi.org/10.5194/esd-4-409-2013, 2013
L. M. Verheijen, V. Brovkin, R. Aerts, G. Bönisch, J. H. C. Cornelissen, J. Kattge, P. B. Reich, I. J. Wright, and P. M. van Bodegom
Biogeosciences, 10, 5497–5515, https://doi.org/10.5194/bg-10-5497-2013, https://doi.org/10.5194/bg-10-5497-2013, 2013
R. Wania, J. R. Melton, E. L. Hodson, B. Poulter, B. Ringeval, R. Spahni, T. Bohn, C. A. Avis, G. Chen, A. V. Eliseev, P. O. Hopcroft, W. J. Riley, Z. M. Subin, H. Tian, P. M. van Bodegom, T. Kleinen, Z. C. Yu, J. S. Singarayer, S. Zürcher, D. P. Lettenmaier, D. J. Beerling, S. N. Denisov, C. Prigent, F. Papa, and J. O. Kaplan
Geosci. Model Dev., 6, 617–641, https://doi.org/10.5194/gmd-6-617-2013, https://doi.org/10.5194/gmd-6-617-2013, 2013
F. Joos, R. Roth, J. S. Fuglestvedt, G. P. Peters, I. G. Enting, W. von Bloh, V. Brovkin, E. J. Burke, M. Eby, N. R. Edwards, T. Friedrich, T. L. Frölicher, P. R. Halloran, P. B. Holden, C. Jones, T. Kleinen, F. T. Mackenzie, K. Matsumoto, M. Meinshausen, G.-K. Plattner, A. Reisinger, J. Segschneider, G. Shaffer, M. Steinacher, K. Strassmann, K. Tanaka, A. Timmermann, and A. J. Weaver
Atmos. Chem. Phys., 13, 2793–2825, https://doi.org/10.5194/acp-13-2793-2013, https://doi.org/10.5194/acp-13-2793-2013, 2013
J. R. Melton, R. Wania, E. L. Hodson, B. Poulter, B. Ringeval, R. Spahni, T. Bohn, C. A. Avis, D. J. Beerling, G. Chen, A. V. Eliseev, S. N. Denisov, P. O. Hopcroft, D. P. Lettenmaier, W. J. Riley, J. S. Singarayer, Z. M. Subin, H. Tian, S. Zürcher, V. Brovkin, P. M. van Bodegom, T. Kleinen, Z. C. Yu, and J. O. Kaplan
Biogeosciences, 10, 753–788, https://doi.org/10.5194/bg-10-753-2013, https://doi.org/10.5194/bg-10-753-2013, 2013
J. Segschneider, A. Beitsch, C. Timmreck, V. Brovkin, T. Ilyina, J. Jungclaus, S. J. Lorenz, K. D. Six, and D. Zanchettin
Biogeosciences, 10, 669–687, https://doi.org/10.5194/bg-10-669-2013, https://doi.org/10.5194/bg-10-669-2013, 2013
Related subject area
Paleobiogeoscience: Climate Connection
The fossil bivalve Angulus benedeni benedeni: a potential seasonally resolved stable-isotope-based climate archive to investigate Pliocene temperatures in the southern North Sea basin
Relationship between extinction magnitude and climate change during major marine and terrestrial animal crises
Investigating controls of shell growth features in a foundation bivalve species: seasonal trends and decadal changes in the California mussel
Monsoonal forcing of cold-water coral growth off southeastern Brazil during the past 160 kyr
What was the source of the atmospheric CO2 increase during the Holocene?
Climate and marine biogeochemistry during the Holocene from transient model simulations
Plant functional diversity affects climate–vegetation interaction
High-resolution regional modelling of natural and anthropogenic radiocarbon in the Mediterranean Sea
Low Florida coral calcification rates in the Plio-Pleistocene
Reconstructions of biomass burning from sediment-charcoal records to improve data–model comparisons
Aligning and synchronization of MIS5 proxy records from Lake Ohrid (FYROM) with independently dated Mediterranean archives: implications for DEEP core chronology
Environmental control on the occurrence of high-coercivity magnetic minerals and formation of iron sulfides in a 640 ka sediment sequence from Lake Ohrid (Balkans)
An inverse modeling approach for tree-ring-based climate reconstructions under changing atmospheric CO2 concentrations
Evidence from "Köppen signatures" of fossil plant assemblages for effective heat transport of Gulf Stream to subarctic North Atlantic during Miocene cooling
Simulating the vegetation response in western Europe to abrupt climate changes under glacial background conditions
An analysis of the contrasting fates of locust swarms on the plains of North America and East Asia
Process based model sheds light on climate sensitivity of Mediterranean tree-ring width
A dynamic climate and ecosystem state during the Paleocene-Eocene Thermal Maximum: inferences from dinoflagellate cyst assemblages on the New Jersey Shelf
Nina M. A. Wichern, Niels J. de Winter, Andrew L. A. Johnson, Stijn Goolaerts, Frank Wesselingh, Maartje F. Hamers, Pim Kaskes, Philippe Claeys, and Martin Ziegler
Biogeosciences, 20, 2317–2345, https://doi.org/10.5194/bg-20-2317-2023, https://doi.org/10.5194/bg-20-2317-2023, 2023
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Fossil bivalves are an excellent climate archive due to their rapidly forming growth increments and long lifespan. Here, we show that the extinct bivalve species Angulus benedeni benedeni can be used to reconstruct past temperatures using oxygen and clumped isotopes. This species has the potential to provide seasonally resolved temperature data for the Pliocene to Oligocene sediments of the North Sea basin. In turn, these past climates can improve our understanding of future climate change.
Kunio Kaiho
Biogeosciences, 19, 3369–3380, https://doi.org/10.5194/bg-19-3369-2022, https://doi.org/10.5194/bg-19-3369-2022, 2022
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I found a good correlation between the mass extinction magnitudes of animals and surface temperature anomalies. The relation is good regardless of the difference between warming and cooling. Marine animals are more likely than tetrapods to become extinct under a habitat temperature anomaly. The extinction magnitudes are marked by abrupt global surface temperature anomalies and coincidental environmental changes associated with abrupt high-energy input by volcanism and impact.
Veronica Padilla Vriesman, Sandra J. Carlson, and Tessa M. Hill
Biogeosciences, 19, 329–346, https://doi.org/10.5194/bg-19-329-2022, https://doi.org/10.5194/bg-19-329-2022, 2022
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The shell of the California mussel contains alternating dark and light calcium carbonate increments that record whether the shell was growing normally under optimal conditions (light) or slowly under sub-optimal conditions (dark). However, the timing and specific environmental controls of growth band formation have not been tested. We investigated these controls and found links between stable seawater temperatures and light bands and highly variable or extreme temperatures and dark bands.
André Bahr, Monika Doubrawa, Jürgen Titschack, Gregor Austermann, Andreas Koutsodendris, Dirk Nürnberg, Ana Luiza Albuquerque, Oliver Friedrich, and Jacek Raddatz
Biogeosciences, 17, 5883–5908, https://doi.org/10.5194/bg-17-5883-2020, https://doi.org/10.5194/bg-17-5883-2020, 2020
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We explore the sensitivity of cold-water corals (CWCs) to environmental changes utilizing a multiproxy approach on a coral-bearing sediment core from off southeastern Brazil. Our results reveal that over the past 160 kyr, CWCs flourished during glacial high-northern-latitude cold events (Heinrich stadials). These periods were associated with anomalous wet phases on the continent enhancing terrigenous nutrient and organic-matter supply to the continental margin, boosting food supply to the CWCs.
Victor Brovkin, Stephan Lorenz, Thomas Raddatz, Tatiana Ilyina, Irene Stemmler, Matthew Toohey, and Martin Claussen
Biogeosciences, 16, 2543–2555, https://doi.org/10.5194/bg-16-2543-2019, https://doi.org/10.5194/bg-16-2543-2019, 2019
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Mechanisms of atmospheric CO2 growth by 20 ppm from 6000 BCE to the pre-industrial period are still uncertain. We apply the Earth system model MPI-ESM-LR for two transient simulations of the climate–carbon cycle. An additional process, e.g. carbonate accumulation on shelves, is required for consistency with ice-core CO2 data. Our simulations support the hypothesis that the ocean was a source of CO2 until the late Holocene when anthropogenic CO2 sources started to affect atmospheric CO2.
Joachim Segschneider, Birgit Schneider, and Vyacheslav Khon
Biogeosciences, 15, 3243–3266, https://doi.org/10.5194/bg-15-3243-2018, https://doi.org/10.5194/bg-15-3243-2018, 2018
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To gain a better understanding of climate and marine biogeochemistry variations over the last 9500 years (the Holocene), we performed non-accelerated model simulations with a global coupled climate and biogeochemistry model forced by orbital parameters and atmospheric greenhouse gases. One main outcome is an increase in the volume of the eastern equatorial Pacific oxygen minimum zone, driven by a slowdown of the large-scale circulation.
Vivienne P. Groner, Thomas Raddatz, Christian H. Reick, and Martin Claussen
Biogeosciences, 15, 1947–1968, https://doi.org/10.5194/bg-15-1947-2018, https://doi.org/10.5194/bg-15-1947-2018, 2018
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We show that plant functional diversity significantly affects climate–vegetation interaction and the climate–vegetation system stability in response to external forcing using a series of coupled land–atmosphere simulation. Our findings raise the question of how realistically Earth system models can actually represent climate–vegetation interaction, considering the incomplete representation of plant functional diversity in the current generation of land surface models.
Mohamed Ayache, Jean-Claude Dutay, Anne Mouchet, Nadine Tisnérat-Laborde, Paolo Montagna, Toste Tanhua, Giuseppe Siani, and Philippe Jean-Baptiste
Biogeosciences, 14, 1197–1213, https://doi.org/10.5194/bg-14-1197-2017, https://doi.org/10.5194/bg-14-1197-2017, 2017
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A high-resolution dynamical model was used to give the first simulation of the distribution of natural and anthropogenic radiocarbon (14C) across the whole Mediterranean Sea. The model correctly simulates the main features of 14C distribution during and after the bomb perturbation. The results demonstrate the major influence of the flux of Atlantic water through the Strait of Gibraltar, and a significant increase in 14C in the Aegean deep water during the Eastern Mediterranean Transient event.
Thomas C. Brachert, Markus Reuter, Stefan Krüger, James S. Klaus, Kevin Helmle, and Janice M. Lough
Biogeosciences, 13, 4513–4532, https://doi.org/10.5194/bg-13-4513-2016, https://doi.org/10.5194/bg-13-4513-2016, 2016
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We have analysed the rate of calcification of fossil reef corals. These measurements are important, because the rate of formation of the skeleton depends on the physical environment in which the corals lived. The rates of skeletal calcification of the fossils were approximately 50 % lower than they are in extant reef corals. This is a likely effect of high water temperatures and/or low carbonate saturation of the water – factors that will also affect coral growth by future global warming.
Jennifer R. Marlon, Ryan Kelly, Anne-Laure Daniau, Boris Vannière, Mitchell J. Power, Patrick Bartlein, Philip Higuera, Olivier Blarquez, Simon Brewer, Tim Brücher, Angelica Feurdean, Graciela Gil Romera, Virginia Iglesias, S. Yoshi Maezumi, Brian Magi, Colin J. Courtney Mustaphi, and Tonishtan Zhihai
Biogeosciences, 13, 3225–3244, https://doi.org/10.5194/bg-13-3225-2016, https://doi.org/10.5194/bg-13-3225-2016, 2016
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We reconstruct spatiotemporal variations in biomass burning since the Last Glacial Maximum (LGM) using the Global Charcoal Database version 3 (including 736 records) and a method to grid the data. LGM to late Holocene burning broadly tracks global and regional climate changes over that interval. Human activities increase fire in the 1800s and then reduce it for most of the 20th century. Burning is now rapidly increasing, particularly in western North America and southeastern Australia.
Giovanni Zanchetta, Eleonora Regattieri, Biagio Giaccio, Bernd Wagner, Roberto Sulpizio, Alex Francke, Hendrik Vogel, Laura Sadori, Alessia Masi, Gaia Sinopoli, Jack H. Lacey, Melanie J. Leng, and Niklas Leicher
Biogeosciences, 13, 2757–2768, https://doi.org/10.5194/bg-13-2757-2016, https://doi.org/10.5194/bg-13-2757-2016, 2016
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Chronology is fundamental in paleoclimatology for understanding timing of events and their origin. In this paper we try to obtain a more detailed chronology for the interval comprised between ca. 140 and 70 ka for the DEEP core in Lake Ohrid using regional independently-dated archives (i.e. speleothems and/or lacustrine succession with well-dated volcanic layers). This allows to insert the DEEP chronology within a common chronological frame between different continental and marine proxy records.
Janna Just, Norbert R. Nowaczyk, Leonardo Sagnotti, Alexander Francke, Hendrik Vogel, Jack H. Lacey, and Bernd Wagner
Biogeosciences, 13, 2093–2109, https://doi.org/10.5194/bg-13-2093-2016, https://doi.org/10.5194/bg-13-2093-2016, 2016
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The magnetic record from Lake Ohrid reflects a strong change in geochemical conditions in the lake. Before 320 ka glacial sediments contain iron sulfides, while later glacials are dominated by siderite. Superimposed on this large-scale pattern are climatic induced changes in the magnetic mineralogy. Glacial and stadial sediments are characterized by relative increases of high- vs. low-coercivity minerals which relate to enhanced erosion in the catchment, possibly due to a sparse vegetation.
É. Boucher, J. Guiot, C. Hatté, V. Daux, P.-A. Danis, and P. Dussouillez
Biogeosciences, 11, 3245–3258, https://doi.org/10.5194/bg-11-3245-2014, https://doi.org/10.5194/bg-11-3245-2014, 2014
T. Denk, G. W. Grimm, F. Grímsson, and R. Zetter
Biogeosciences, 10, 7927–7942, https://doi.org/10.5194/bg-10-7927-2013, https://doi.org/10.5194/bg-10-7927-2013, 2013
M.-N. Woillez, M. Kageyama, N. Combourieu-Nebout, and G. Krinner
Biogeosciences, 10, 1561–1582, https://doi.org/10.5194/bg-10-1561-2013, https://doi.org/10.5194/bg-10-1561-2013, 2013
G. Yu, X. Ke, H. D. Shen, and Y. F. Li
Biogeosciences, 10, 1441–1449, https://doi.org/10.5194/bg-10-1441-2013, https://doi.org/10.5194/bg-10-1441-2013, 2013
R. Touchan, V. V. Shishov, D. M. Meko, I. Nouiri, and A. Grachev
Biogeosciences, 9, 965–972, https://doi.org/10.5194/bg-9-965-2012, https://doi.org/10.5194/bg-9-965-2012, 2012
A. Sluijs and H. Brinkhuis
Biogeosciences, 6, 1755–1781, https://doi.org/10.5194/bg-6-1755-2009, https://doi.org/10.5194/bg-6-1755-2009, 2009
Cited articles
Berger, A.: Long-term variations of daily insolation and Quaternary climatic change, J. Atmos. Sci., 35, 2362–2367, 1978.
Bigelow, N. H., Brubaker, L. B., Edwards, M. E., Harrison, S. P. Prentice, I. C., Anderson, M., Andreev, A. A., Bartlein, P. J., Christensen, T. R., Cramer, W. , Kaplan, J. O. , Lozhkin, A. V., Matveyava, N. V., Murray, D. F., McGuire, A. D., Razzhivin, V. Y., Ritchie, J. C., Smith, B., Walker, D. A., Gajewski, K., Wolf, V., Holmquist, B. H., Igarashi, Y., Kremenetskii, K., Paus, A., Pisaric, 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., 108, 8170, https://doi.org/10.1029/2002JD002558, 2003.
Braconnot, P., Otto-Bliesner, B., Harrison, S., Joussaume, S., Peterchmitt, J.-Y., Abe-Ouchi, A., Crucifix, M., Driesschaert, E., Fichefet, Th., Hewitt, C. D., Kageyama, M., Kitoh, A., Laîné, A., Loutre, M.-F., Marti, O., Merkel, U., Ramstein, G., Valdes, P., Weber, S. L., Yu, Y., and Zhao, Y.: Results of PMIP2 coupled simulations of the Mid-Holocene and Last Glacial Maximum – Part 1: experiments and large-scale features, Clim. Past, 3, 261–277, https://doi.org/10.5194/cp-3-261-2007, 2007.
Brovkin, V., Raddatz, T., Reick, C., Claussen, M., and Gayler, V.: Global biogeophysical interaction between forest and climate, Geophys. Res. Lett., 36, L07405, https://doi.org/10.1029/2009GL037543, 2009.
Brovkin, V., Boysen, L., Raddatz, T., Gayler, V., Loew, A., and Claussen, M.: Evaluation of vegetation cover and land-surface albedo in MPI-ESM CMIP5 simulations, J. Adv. Model. Earth Syst., 5, 48–57, https://doi.org/10.1029/2012MS000169, 2013.
Claussen, M. and Esch, M.,: Biomes computed from simulated climatologies, Clim. Dynam., 9, 235–243, 1994.
Collatz, G. J., Ribas-Crabo, M., and Berry, J. A.: Coupled photosynthesis-stomatal conductance model for C4 plants, Aust. J. Plant Physiol., 19, 519–538, 1992.
Crowley, T. J.: Ice age terrestrial carbon changes revisited, Global Biogeochem. Cy., 9, 377–389, 1995.
Crucifix, M., Betts, R. A., and Hewitt, C. D.: Pre-industrial-potential and Last Glacial Maximum global vegetation simulated with a coupled climate-biosphere model: Diagnosis of bioclimatic relationships, Glob. Planet. Change, 45, 295–312, 2005.
Dallmeyer, A., Claussen, M., and Otto, J.: Contribution of oceanic and vegetation feedbacks to Holocene climate change in monsoonal Asia, Clim. Past, 6, 195–218, https://doi.org/10.5194/cp-6-195-2010, 2010.
Elenga, H., Peyron, O., Bonnefille, R., Jolly, D., Cheddadi, R., Guiot, J., Andrieu, V., Bottema, S., Buchet, G., De Beaulieu, J.-L., Hamilton, A. C., Maley, J., Marchant, R., Perez-Obiol, R., Reille, M., Riollet, G., Scott, L., Straka, H., Taylor, D., Van Campo, E., Vincens, A., Laarif, F., and Jonson, H.: Pollen-based biome reconstruction for southern Europe and Africa 18,000 yr bp, J. Biogeogr., 27, 621–634, 2000.
Farquhar, G. D., Caemmerer, S. V., and Berry, J. A.: A biochemical-model of photosynthetic CO2 assimilation in leaves of C3 species, Planta, 149, 78–90, 1980.
Hansen, M., DeFries, R., Townshend, J. R., Carroll, M., Dimiceli, C., and Sohlberg, R.: 2001 Percent Tree Cover, Collection 4, Vegetation Continuous Fields MOD44B,, available at: http://glcf.umiacs.umd.edu/data/vcf/, (last access: 13 July 2007), Univ. of Md., College Park, 2007.
Hantel, M. (Ed.): Observed Global Climate, Landolt-Börnstein, Group V, Geophysics, Vol. 6., Springer, Berlin Heidelberg, 2005.
Harrison, S. P. and Prentice, I. C.: Climate and CO2 controls on global vegetation distribution at the last glacial maximum: analysis based on palaeovegetation data, biome modelling and palaeoclimate simulations, Glob. Change Biol., 9, 983–1004, 2003.
Jahn, A., Claussen, M., Ganopolski, A., and Brovkin, V.: Quantifying the effect of vegetation dynamics on the climate of the Last Glacial Maximum, Clim. Past, 1, 1–7, https://doi.org/10.5194/cp-1-1-2005, 2005.
Jungclaus, J. H., Keenlyside, N., Botzet, M., Haak, H., Luo, J. J., Latif, M., Marotzke, J., Mikolajewicz, U., and Roeckner, E.: Ocean circulation and tropical variability in the coupled model ECHAM5/MPI-OM, J. Climate, 19, 3952–3972, 2006.
Kattge, J., Knorr, W., Raddatz, T., and Wirth, C.: Quantifying photosynthetic capacity and its relationship to leaf nitrogen content for global-scale terrestrial biosphere models, Glob. Change Biol., 15, 976–991, https://doi.org/10.1111/j.1365-2486.2008.01744.x, 2009.
Kubatzki, C. and Claussen, M.: Simulation of the global biogeophysical interactions during the last glacial maximum, Clim. Dynam., 14, 461–471, 1998.
Kutzbach, J. E., Gallimore, R., Harrison, S., Behling, P., Selin, R., and Laarif, F.: Climate and biome simulations for the past 21,000 years, Quarternary Sci. Rev., 17, 473–506, 1998.
Levis, S. and Foley, J. A.: CO2, climate-vegetation feedbacks at the Last Glacial Maximum, J. Geophys. Res., 104, 31191–31198, 1999
Marchant, R., Cleef, A., Harrison, S. P., Hooghiemstra, H., Markgraf, V., van Boxel, J., Ager, T., Almeida, L., Anderson, R., Baied, C., Behling, H., Berrio, J. C., Burbridge, R., Björck, S., Byrne, R., Bush, M., Duivenvoorden, J., Flenley, J., De Oliveira, P., van Geel, B., Graf, K., Gosling, W. D., Harbele, S., van der Hammen, T., Hansen, B., Horn, S., Kuhry, P., Ledru, M.-P., Mayle, F., Leyden, B., Lozano-García, S., Melief, A. M., Moreno, P., Moar, N. T., Prieto, A., van Reenen, G., Salgado-Labouriau, M., Schäbitz, F., Schreve-Brinkman, E. J., and Wille, M.: Pollen-based biome reconstructions for Latin America at 0, 6000 and 18 000 radiocarbon years ago, Clim. Past, 5, 725–767, https://doi.org/10.5194/cp-5-725-2009, 2009.
Mikolajewicz, U., Vizcaino, M., Jungclaus, J., and Schurgers G.: Effect of ice sheet interactions in anthropogenic climate change simulations, Geophys. Res. Lett., 34, L18706, https://doi.org/10.1029/2007GL031173, 2007.
Otto, J., Raddatz, T., and Claussen, M.: Climate variability-induced uncertainty in mid-Holocene atmosphere-ocean-vegetation feedbacks. Geophys. Rev. Lett., 36, L23710, https://doi.org/10.1029/2009GL041457, 2009.
Otto, J., Raddatz, T., and Claussen, M.: Strength of forest-albedo feedback in mid-Holocene climate simulations, Clim. Past, 7, 1027–1039, https://doi.org/10.5194/cp-7-1027-2011, 2011.
Peltier, W.: Global glacial isostasy and the surface of the ice-age Earth: the ICE-5G (VM2) Model and GRACE, Annu. Rev. Earth Pl. Sci., 32, 111–149, 2004.
Pongratz, J., Reick, C., Raddatz, T., and Claussen, M.: A reconstruction of global agricultural areas and land cover for the last millennium, Global Biogeochem. Cy., 22, GB3018, https://doi.org/10.1029/2007GB003153, 2008.
Prentice, I. C., Jolly, D., and BIOME 6000 members: Mid-Holocene and glacial-maximum vegetation geography of the northern continents and Africa, J. Biogeogr., 27, 507–519, 2000.
Prentice, I. C., Harrison, S. P., and Bartlein, P. J.: Global vegetation and terrestrial carbon cycle changes after the last ice age, New Phytol., 189, 988–998, 2011.
Raddatz, T. J., Reick, C. H., Knorr, W., Kattge, J., Roeckner, E., Schnur, R., Schnitzler, K.-G., Wetzel, P., and Jungclaus, J.: Will the tropical land biosphere dominate the climate-carbon cycle feedback during the twenty-first century?, Clim. Dynam., 29, 565–574, 2007.
Reick, C. H., Raddatz, T., Brovkin, V., and Gayler, V.: The representation of natural and anthropogenic landcover change in MPI-ESM, J. Adv. Model. Earth Syst., https://doi.org/10.1002/jame.20022, 2013.
Roche, D. M., Dokken, T. M., Goosse, H., Renssen, H., and Weber, S. L.: Climate of the Last Glacial Maximum: sensitivity studies and model-data comparison with the LOVECLIM coupled model, Clim. Past, 3, 205–224, https://doi.org/10.5194/cp-3-205-2007, 2007.
Rohde, R., Muller, R., Jacobsen, R., Perlmutter, S., Rosenfeld, A., Wurtele, J., Curry, J., Wickhams, C., and Mosher, S.: Berkeley Earth Temperature Averaging Process, Geoinfor. Geostat.: An Overview $1:2$, https://doi.org/10.4172/gigs.1000103, 2013
Selent, K.: Last Glacial Maximum vegetation: results from simulations with the MPI Earth System Model (MPI-ESM), Master Thesis, University Hamburg, Hamburg, 2012.
Stein, U. and Alpert, P.: Factor separation in numerical simulations, J. Atmos. Sci., 50, 2107–2115, 1993.
Stevens B., Crueger, T., Esch, M., Giorgetta, M., Mauritsen, T., Rast, S., Schmidt, H., Bader, J., Block, K., Brokopf, R., Fast, I., Kinne, S., Kornblueh, L., Lohmann, U., Pincus, R., Reichler, T., Salzmann, M., and Roeckner, E.: The Atmospheric Component of the MPI-M Earth System Model: ECHAM6, J. Adv. Model. Earth Syst., 5, 1–27, https://doi.org/10.1002/jame.20015, 2013.
Tarasov, P. E., Webb III, T., Andreev, A. A., Afanaseva, N. B., Berezina, N. A., Bezusko, L. G., Blyakharchuk, T. A., Bolikhovskaya, N. S., Cheddadi, R., Chernavskaya, M. M., Chernova, G. M., Dorofeyuk, N.I., Dirksen, V. G., Elina, G. A., Filimonova, L. V., Glebov, F. Z., Guiot, J., Gunova, V. S., Harrison, S. P., Jolly, D., Khomutova, V. I., Kvavadze, E. V., Osipova, I. M., Panova, N. K., Prentice, I. C., Saarse, L., Sevastyanov, D. V., Volkova, V. S., and Zernitskaya, V. P.: Present-day and mid-Holocene biomes reconstructed from pollen and plant macrofossil data from the former Soviet Union and Mongolia, J. Biogeogr., 25, 1029–1053, 2000.
Woillez, M.-N., Kageyama, M., Krinner, G., de Noblet-Ducoudré, N., Viovy, N., and Mancip, M.: Impact of CO2 and climate on the Last Glacial Maximum vegetation: results from the ORCHIDEE/IPSL models, Clim. Past, 7, 557–577, https://doi.org/10.5194/cp-7-557-2011, 2011.
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