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Regional Dust Modelling on Geological Time Scales: the Evolution of the Chinese Loess Plateau

Yaping Shao
Institute for Geophysics and Meteorology, University of Cologne, Cologne, Germany

 

Simple budget calculations for the Chinese Loess Plateau suggest that aeolian transport and deposition must have been very significant over Late Cenozoic time scales. But our quantitative understanding of the processes is so far very limited,  based mostly on geological proxies. In recent years, aeolian models have been integrated into global and regional climate models to allow quantitative assessment and prediction of the dust cycle. Simulations show that under present climate conditions, the Chinese Loess Plateau remains a significant dust sink region. Paleodust modeling has not been possible until recently. With the improved skills of Global Climate Models (GCMs), paleoclimate simulations have been performed with credible results. For example, in PMIP3 (Project for Model Intercomparison Paleo Phase 3), more than 20 GCMs (among which several are Earth-System Models) have been used to simulate the climate during the Last Glacial Maximum (LGM). Here, we use the PMIP3 data as the background input and simulate dust processes using a regional climate model, coupled with an aeolian model. Simulations are run for both the present-day and paleo-climatic conditions. Comparison of the model simulations for the two different climates are presented, with emphases on loess sources/sinks and the quantification of the dust cycle for the Present and at the LGM.