| Summary: | Increasing abrupt and extreme climate events that can cause catastrophic impact on society have been observed with the global warming and these abrupt, extreme and widespread climate changes with major impacts have also occurred repeatedly over the past, when the Earth system was forced across thresholds. The most-known are the Dansgaard–Oeschger (DO) events and the Heinrich (H) events that occurred during the last glacial period. However, what’s their causes (Insolation, CO2, Fresh water and Ice sheet) and impacts (Hemispheric consistency or regional discrepancy) are still in debate. In my Ph.D thesis, we plan use an innovative approach combining global (HadCM3) and regional (RegCM4) climate models as well as vegetation model (BIOME4) to understand the temporal and spatial climate diversity of six Heinrich events during the last glacial over East Asia and the work strategy of this method is the following: Step 1: In order to provide global atmospheric boundary conditions to RegCM4, HadCM3 will be used for global climate simulations for each H event. Step 2: RegCM4 will be driven by the outputs of the HadCM3 simulations to simulate the regional climate over East Asia. Step 3: The climate outputs of RegCM4 will then be used to drive BIOME4 to simulate the vegetation and land surface characteristics. Step 4: The RegCM4 simulations will be repeated with the updated vegetation provided in step 3 as boundary condition. The results obtained will allow to explore the impact of different external forcings and internal feedbacks. In particular, comparing the outputs of step 1 and 2 allows to investigate what’s the “added value†of regional climate modelling. Comparing step 2 and step 4 allows to investigate the impact of vegetation. Finally, a comprehensive analysis of all the results will help to understand what has caused the spatiotemporal discrepancies of the H events climate in East Asia.
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