@article{DongesDonnerTrauthetal.2011, author = {Donges, Jonathan and Donner, Reik Volker and Trauth, Martin H. and Marwan, Norbert and Schellnhuber, Hans Joachim and Kurths, J{\"u}rgen}, title = {Nonlinear detection of paleoclimate-variability transitions possibly related to human evolution}, series = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {108}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, number = {51}, publisher = {National Acad. of Sciences}, address = {Washington}, issn = {0027-8424}, doi = {10.1073/pnas.1117052108}, pages = {20422 -- 20427}, year = {2011}, abstract = {Potential paleoclimatic driving mechanisms acting on human evolution present an open problem of cross-disciplinary scientific interest. The analysis of paleoclimate archives encoding the environmental variability in East Africa during the past 5 Ma has triggered an ongoing debate about possible candidate processes and evolutionary mechanisms. In this work, we apply a nonlinear statistical technique, recurrence network analysis, to three distinct marine records of terrigenous dust flux. Our method enables us to identify three epochs with transitions between qualitatively different types of environmental variability in North and East Africa during the (i) Middle Pliocene (3.35-3.15 Ma B. P.), (ii) Early Pleistocene (2.25-1.6 Ma B. P.), and (iii) Middle Pleistocene (1.1-0.7 Ma B. P.). A deeper examination of these transition periods reveals potential climatic drivers, including (i) large-scale changes in ocean currents due to a spatial shift of the Indonesian throughflow in combination with an intensification of Northern Hemisphere glaciation, (ii) a global reorganization of the atmospheric Walker circulation induced in the tropical Pacific and Indian Ocean, and (iii) shifts in the dominating temporal variability pattern of glacial activity during the Middle Pleistocene, respectively. A reexamination of the available fossil record demonstrates statistically significant coincidences between the detected transition periods and major steps in hominin evolution. This result suggests that the observed shifts between more regular and more erratic environmental variability may have acted as a trigger for rapid change in the development of humankind in Africa.}, language = {en} } @misc{FrielerLevermannElliottetal.2015, author = {Frieler, Katja and Levermann, Anders and Elliott, J. and Heinke, J. and Arneth, A. and Bierkens, M. F. P. and Ciais, Philippe and Clark, D. B. and Deryng, D. and Doell, P. and Falloon, P. and Fekete, B. and Folberth, Christian and Friend, A. D. and Gellhorn, C. and Gosling, S. N. and Haddeland, I. and Khabarov, N. and Lomas, M. and Masaki, Y. and Nishina, K. and Neumann, K. and Oki, T. and Pavlick, R. and Ruane, A. C. and Schmid, E. and Schmitz, C. and Stacke, T. and Stehfest, E. and Tang, Q. and Wisser, D. and Huber, V. and Piontek, Franziska and Warszawski, L. and Schewe, Jacob and Lotze-Campen, Hermann and Schellnhuber, Hans Joachim}, title = {A framework for the cross-sectoral integration of multi-model impact projections}, series = {Earth system dynamics}, journal = {Earth system dynamics}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-407968}, pages = {14}, year = {2015}, abstract = {Climate change and its impacts already pose considerable challenges for societies that will further increase with global warming (IPCC, 2014a, b). Uncertainties of the climatic response to greenhouse gas emissions include the potential passing of large-scale tipping points (e.g. Lenton et al., 2008; Levermann et al., 2012; Schellnhuber, 2010) and changes in extreme meteorological events (Field et al., 2012) with complex impacts on societies (Hallegatte et al., 2013). Thus climate change mitigation is considered a necessary societal response for avoiding uncontrollable impacts (Conference of the Parties, 2010). On the other hand, large-scale climate change mitigation itself implies fundamental changes in, for example, the global energy system. The associated challenges come on top of others that derive from equally important ethical imperatives like the fulfilment of increasing food demand that may draw on the same resources. For example, ensuring food security for a growing population may require an expansion of cropland, thereby reducing natural carbon sinks or the area available for bio-energy production. So far, available studies addressing this problem have relied on individual impact models, ignoring uncertainty in crop model and biome model projections. Here, we propose a probabilistic decision framework that allows for an evaluation of agricultural management and mitigation options in a multi-impact-model setting. Based on simulations generated within the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), we outline how cross-sectorally consistent multi-model impact simulations could be used to generate the information required for robust decision making. Using an illustrative future land use pattern, we discuss the trade-off between potential gains in crop production and associated losses in natural carbon sinks in the new multiple crop-and biome-model setting. In addition, crop and water model simulations are combined to explore irrigation increases as one possible measure of agricultural intensification that could limit the expansion of cropland required in response to climate change and growing food demand. This example shows that current impact model uncertainties pose an important challenge to long-term mitigation planning and must not be ignored in long-term strategic decision making.}, language = {en} } @article{FrielerLevermannElliottetal.2015, author = {Frieler, Katja and Levermann, Anders and Elliott, J. and Heinke, Jens and Arneth, A. and Bierkens, M. F. P. and Ciais, Philippe and Clark, D. B. and Deryng, D. and Doell, P. and Falloon, P. and Fekete, B. and Folberth, Christian and Friend, A. D. and Gellhorn, C. and Gosling, S. N. and Haddeland, I. and Khabarov, N. and Lomas, M. and Masaki, Y. and Nishina, K. and Neumann, K. and Oki, T. and Pavlick, R. and Ruane, A. C. and Schmid, E. and Schmitz, C. and Stacke, T. and Stehfest, E. and Tang, Q. and Wisser, D. and Huber, Veronika and Piontek, Franziska and Warszawski, Lila and Schewe, Jacob and Lotze-Campen, Hermann and Schellnhuber, Hans Joachim}, title = {A framework for the cross-sectoral integration of multi-model impact projections}, series = {Earth system dynamics}, volume = {6}, journal = {Earth system dynamics}, number = {2}, publisher = {Copernicus}, address = {G{\"o}ttingen}, issn = {2190-4979}, doi = {10.5194/esd-6-447-2015}, pages = {447 -- 460}, year = {2015}, abstract = {Climate change and its impacts already pose considerable challenges for societies that will further increase with global warming (IPCC, 2014a, b). Uncertainties of the climatic response to greenhouse gas emissions include the potential passing of large-scale tipping points (e.g. Lenton et al., 2008; Levermann et al., 2012; Schellnhuber, 2010) and changes in extreme meteorological events (Field et al., 2012) with complex impacts on societies (Hallegatte et al., 2013). Thus climate change mitigation is considered a necessary societal response for avoiding uncontrollable impacts (Conference of the Parties, 2010). On the other hand, large-scale climate change mitigation itself implies fundamental changes in, for example, the global energy system. The associated challenges come on top of others that derive from equally important ethical imperatives like the fulfilment of increasing food demand that may draw on the same resources. For example, ensuring food security for a growing population may require an expansion of cropland, thereby reducing natural carbon sinks or the area available for bio-energy production. So far, available studies addressing this problem have relied on individual impact models, ignoring uncertainty in crop model and biome model projections. Here, we propose a probabilistic decision framework that allows for an evaluation of agricultural management and mitigation options in a multi-impact-model setting. Based on simulations generated within the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), we outline how cross-sectorally consistent multi-model impact simulations could be used to generate the information required for robust decision making. Using an illustrative future land use pattern, we discuss the trade-off between potential gains in crop production and associated losses in natural carbon sinks in the new multiple crop-and biome-model setting. In addition, crop and water model simulations are combined to explore irrigation increases as one possible measure of agricultural intensification that could limit the expansion of cropland required in response to climate change and growing food demand. This example shows that current impact model uncertainties pose an important challenge to long-term mitigation planning and must not be ignored in long-term strategic decision making.}, language = {en} } @article{GanopolskiWinkelmannSchellnhuber2016, author = {Ganopolski, A. and Winkelmann, Ricarda and Schellnhuber, Hans Joachim}, title = {Critical insolation-CO2 relation for diagnosing past and future glacial inception}, series = {Nature : the international weekly journal of science}, volume = {529}, journal = {Nature : the international weekly journal of science}, publisher = {Nature Publ. Group}, address = {London}, issn = {0028-0836}, doi = {10.1038/nature16494}, pages = {200 -- U159}, year = {2016}, abstract = {The past rapid growth of Northern Hemisphere continental ice sheets, which terminated warm and stable climate periods, is generally attributed to reduced summer insolation in boreal latitudes(1-3). Yet such summer insolation is near to its minimum at present(4), and there are no signs of a new ice age(5). This challenges our understanding of the mechanisms driving glacial cycles and our ability to predict the next glacial inception(6). Here we propose a critical functional relationship between boreal summer insolation and global carbon dioxide (CO2) concentration, which explains the beginning of the past eight glacial cycles and might anticipate future periods of glacial inception. Using an ensemble of simulations generated by an Earth system model of intermediate complexity constrained by palaeoclimatic data, we suggest that glacial inception was narrowly missed before the beginning of the Industrial Revolution. The missed inception can be accounted for by the combined effect of relatively high late-Holocene CO2 concentrations and the low orbital eccentricity of the Earth(7). Additionally, our analysis suggests that even in the absence of human perturbations no substantial build-up of ice sheets would occur within the next several thousand years and that the current interglacial would probably last for another 50,000 years. However, moderate anthropogenic cumulative CO2 emissions of 1,000 to 1,500 gigatonnes of carbon will postpone the next glacial inception by at least 100,000 years(8,9). Our simulations demonstrate that under natural conditions alone the Earth system would be expected to remain in the present delicately balanced interglacial climate state, steering clear of both large-scale glaciation of the Northern Hemisphere and its complete deglaciation, for an unusually long time.}, language = {en} } @misc{LentonRockstroemGaffneyetal.2019, author = {Lenton, Timothy M. and Rockstroem, Johan and Gaffney, Owen and Rahmstorf, Stefan and Richardson, Katherine and Steffen, Will and Schellnhuber, Hans Joachim}, title = {Climate tipping points - too risky to bet against : Comment}, series = {Nature : the international weekly journal of science}, volume = {575}, journal = {Nature : the international weekly journal of science}, number = {7784}, publisher = {Nature Publ. Group}, address = {London}, issn = {0028-0836}, doi = {10.1038/d41586-019-03595-0}, pages = {592 -- 595}, year = {2019}, language = {en} } @misc{LevermannPetoukhovScheweetal.2016, author = {Levermann, Anders and Petoukhov, Vladimir and Schewe, Jacob and Schellnhuber, Hans Joachim}, title = {Abrupt monsoon transitions as seen in paleorecords can be explained by moisture-advection feedback}, series = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {113}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, publisher = {National Acad. of Sciences}, address = {Washington}, issn = {0027-8424}, doi = {10.1073/pnas.1603130113}, pages = {E2348 -- E2349}, year = {2016}, language = {en} } @book{RahmstorfSchellnhuber2020, author = {Rahmstorf, Stefan and Schellnhuber, Hans Joachim}, title = {Der Klimawandel}, series = {Schriftenreihe / Bundeszentrale f{\"u}r politische Bildung ; Band 10520}, journal = {Schriftenreihe / Bundeszentrale f{\"u}r politische Bildung ; Band 10520}, publisher = {Bundeszentrale f{\"u}r politische Bildung}, address = {Bonn}, isbn = {978-3-7425-0520-0}, pages = {144}, year = {2020}, language = {de} } @book{RahmstorfSchellnhuber2006, author = {Rahmstorf, Stefan and Schellnhuber, Hans Joachim}, title = {Der Klimawandel}, series = {Becksche Reihe}, volume = {2366}, journal = {Becksche Reihe}, publisher = {Beck}, address = {M{\"u}nchen}, isbn = {3-406-50866-9}, pages = {144 S.}, year = {2006}, language = {de} } @article{SchellnhuberCrutzenClarketal.2005, author = {Schellnhuber, Hans Joachim and Crutzen, P. J. and Clark, W. C. and Hunt, J.}, title = {Earth system analysis for sustainability}, issn = {0013-9157}, year = {2005}, abstract = {Anthropogenic interference has resulted in climate change, ocean acidification, eutrophication and toxic pollution of the earth and it's ecosystems. The Earth System Analysis is an international research program on global environmental change to understand these processes in order to work towards global sustainability}, language = {en} } @misc{ShanGuanHubaceketal.2018, author = {Shan, Yuli and Guan, Dabo and Hubacek, Klaus and Zheng, Bo and Davis, Steven J. and Jia, Lichao and Liu, Jianghua and Liu, Zhu and Fromer, Neil and Mi, Zhifu and Meng, Jing and Deng, Xiangzheng and Li, Yuan and Lin, Jintai and Schroeder, Heike and Weisz, Helga and Schellnhuber, Hans Joachim}, title = {City-level climate change mitigation in China}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1096}, issn = {1866-8372}, doi = {10.25932/publishup-47154}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-471541}, pages = {18}, year = {2018}, abstract = {As national efforts to reduce CO2 emissions intensify, policy-makers need increasingly specific, subnational information about the sources of CO2 and the potential reductions and economic implications of different possible policies. This is particularly true in China, a large and economically diverse country that has rapidly industrialized and urbanized and that has pledged under the Paris Agreement that its emissions will peak by 2030. We present new, city level estimates of CO2 emissions for 182 Chinese cities, decomposed into 17 different fossil fuels, 46 socioeconomic sectors, and 7 industrial processes. We find that more affluent cities have systematically lower emissions per unit of gross domestic product (GDP), supported by imports from less affluent, industrial cities located nearby. In turn, clusters of industrial cities are supported by nearby centers of coal or oil extraction. Whereas policies directly targeting manufacturing and electric power infrastructure would drastically undermine the GDP of industrial cities, consumption based policies might allow emission reductions to be subsidized by those with greater ability to pay. In particular, sector based analysis of each city suggests that technological improvements could be a practical and effective means of reducing emissions while maintaining growth and the current economic structure and energy system. We explore city-level emission reductions under three scenarios of technological progress to show that substantial reductions (up to 31\%) are possible by updating a disproportionately small fraction of existing infrastructure.}, language = {en} }