Simulating Earth’s Last Great Global Warming Event


About 14,500 years ago Greenland’s temperature increased by 15 degrees C over a period of a century or so, the last great global warming event. DOE- and NSF-funded scientists have completed the first computer simulation of this event using the state-of-art Community Climate System Model, CCSM3 climate model, and the Jaguar supercomputer at Oak-Ridge National Laboratory by modeling events from 22,000 to 14,000 years ago. The model reproduces several major features of the deglacial climate evolution, suggesting a good agreement in climate sensitivity between the model and observations. The Liu et al. study initiates a new era of paleoclimate modeling based on astronomical theory, ice-sheet reconstructions, and the history of greenhouse gas concentrations. It offers the unique possibility to study the full spatiotemporal behavior of climate change, including the mechanisms of abrupt climate change, and to directly compare the resulting temporal features with paleoclimate data, for example, from sediment cores and ice cores. Climate models, together with high performance computing resources like those provided by DOE, are tools to promote our understanding of the climate system and predict its future evolution.


Z. Liu, B. Otto-Bliesner, F. He, E. Brady, P. Clark, J. Lynch-Steiglitz, A. Carlson, W. Curry, E. Brook, R. Jacob, D. Erickson, J. Kutzbach, J. Cheng, 2009: Transient simulation of deglacial Climate Evolution with a new mechanism for Bolling-Allerod warming. Science, 325, 310(2009).