Articles | Volume 16, issue 1
https://doi.org/10.5194/cp-16-117-2020
© Author(s) 2020. 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-16-117-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Jan 2020
Research article |
| 15 Jan 2020
| 15 Jan 2020
The end of the African humid period as seen by a transient comprehensive Earth system model simulation of the last 8000 years
Anne Dallmeyer
CORRESPONDING AUTHOR
The Land in the Earth System, Max Planck Institute for Meteorology, Bundesstrasse 53, 20146 Hamburg, Germany
Martin Claussen
The Land in the Earth System, Max Planck Institute for Meteorology, Bundesstrasse 53, 20146 Hamburg, Germany
Meteorological Institute, Centrum für Erdsystemforschung und
Nachhaltigkeit (CEN), Universität Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany
Stephan J. Lorenz
The Ocean in the Earth System, Max Planck Institute for Meteorology, Bundesstrasse 53, 20146 Hamburg, Germany
Timothy Shanahan
The University of Texas at Austin, Department of Geological Sciences, 1 University Station C9000, Austin, Texas 78712, USA
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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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Anne Dallmeyer, Martin Claussen, Stephan J. Lorenz, Michael Sigl, Matthew Toohey, and Ulrike Herzschuh
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Victor Brovkin, Stephan Lorenz, Thomas Raddatz, Tatiana Ilyina, Irene Stemmler, Matthew Toohey, and Martin Claussen
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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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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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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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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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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.
Johann H. Jungclaus, Edouard Bard, Mélanie Baroni, Pascale Braconnot, Jian Cao, Louise P. Chini, Tania Egorova, Michael Evans, J. Fidel González-Rouco, Hugues Goosse, George C. Hurtt, Fortunat Joos, Jed O. Kaplan, Myriam Khodri, Kees Klein Goldewijk, Natalie Krivova, Allegra N. LeGrande, Stephan J. Lorenz, Jürg Luterbacher, Wenmin Man, Amanda C. Maycock, Malte Meinshausen, Anders Moberg, Raimund Muscheler, Christoph Nehrbass-Ahles, Bette I. Otto-Bliesner, Steven J. Phipps, Julia Pongratz, Eugene Rozanov, Gavin A. Schmidt, Hauke Schmidt, Werner Schmutz, Andrew Schurer, Alexander I. Shapiro, Michael Sigl, Jason E. Smerdon, Sami K. Solanki, Claudia Timmreck, Matthew Toohey, Ilya G. Usoskin, Sebastian Wagner, Chi-Ju Wu, Kok Leng Yeo, Davide Zanchettin, Qiong Zhang, and Eduardo Zorita
Geosci. Model Dev., 10, 4005–4033, https://doi.org/10.5194/gmd-10-4005-2017, https://doi.org/10.5194/gmd-10-4005-2017, 2017
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Climate model simulations covering the last millennium provide context for the evolution of the modern climate and for the expected changes during the coming centuries. They can help identify plausible mechanisms underlying palaeoclimatic reconstructions. Here, we describe the forcing boundary conditions and the experimental protocol for simulations covering the pre-industrial millennium. We describe the PMIP4 past1000 simulations as contributions to CMIP6 and additional sensitivity experiments.
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.
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.
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
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
K. Lohmann, J. H. Jungclaus, D. Matei, J. Mignot, M. Menary, H. R. Langehaug, J. Ba, Y. Gao, O. H. Otterå, W. Park, and S. Lorenz
Ocean Sci., 10, 227–241, https://doi.org/10.5194/os-10-227-2014, https://doi.org/10.5194/os-10-227-2014, 2014
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
M. Claussen, K. Selent, V. Brovkin, T. Raddatz, and V. Gayler
Biogeosciences, 10, 3593–3604, https://doi.org/10.5194/bg-10-3593-2013, https://doi.org/10.5194/bg-10-3593-2013, 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
Subject: Vegetation Dynamics | Archive: Modelling only | Timescale: Holocene
The challenge of comparing pollen-based quantitative vegetation reconstructions with outputs from vegetation models – a European perspective
How does the explicit treatment of convection alter the precipitation–soil hydrology interaction in the mid-Holocene African humid period?
Effect of nitrogen limitation and soil biophysics on Holocene greening of the Sahara
Holocene vegetation transitions and their climatic drivers in MPI-ESM1.2
Harmonising plant functional type distributions for evaluating Earth system models
Controls on fire activity over the Holocene
North African vegetation–precipitation feedback in early and mid-Holocene climate simulations with CCSM3-DGVM
Comparing modelled fire dynamics with charcoal records for the Holocene
Climate and CO2 modulate the C3/C4 balance and δ13C signal in simulated vegetation
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
Short summary
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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.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
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
R. Rachmayani, M. Prange, and M. Schulz
Clim. Past, 11, 175–185, https://doi.org/10.5194/cp-11-175-2015, https://doi.org/10.5194/cp-11-175-2015, 2015
Short summary
Short summary
The role of vegetation-precipitation feedbacks in modifying the North African rainfall response to enhanced early to mid-Holocene summer insolation is analysed using the climate-vegetation model CCSM3-DGVM. Dynamic vegetation amplifies the positive early to mid-Holocene summer precipitation anomaly by ca. 20% in the Sahara-Sahel region. The primary vegetation feedback operates through surface latent heat flux anomalies by canopy evapotranspiration and their effect on the African easterly jet.
T. Brücher, V. Brovkin, S. Kloster, J. R. Marlon, and M. J. Power
Clim. Past, 10, 811–824, https://doi.org/10.5194/cp-10-811-2014, https://doi.org/10.5194/cp-10-811-2014, 2014
O. Flores, E. S. Gritti, and D. Jolly
Clim. Past, 5, 431–440, https://doi.org/10.5194/cp-5-431-2009, https://doi.org/10.5194/cp-5-431-2009, 2009
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Short summary
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.
We analyse the end of the African humid period (AHP) in a transient Holocene simulation...
