主讲:Gilles Ramstein
时间:2019年12月18日,周三,10:00—11:00
地点:物理楼北539
主持/联系:刘永岗
摘要:
A century ago, the pioneering book published in 1924 Die Klimate der geologischen Vorzeit explained byplate motion the evolution of vegetation revealed in sedimentary records. Nevertheless, they did not invokeclimate changes. In the second part of the 20th century, the intricate relationship between tectonics, longtermcarbon cycle, and climate was depicted by Walker (1981). Since these major steps, climate modeling ofthe Earth system kept on improving and including more and more components and processes to enable theinvestigation of deep time periods using general circulation model that can account for atmosphere and oceandynamics. Here we illustrate long but drastic climate changes clearly related with tectonics, through threedifferent examples: (1) the crucial role of paleogeography (continental distribution) to explain the drawdownof atmospheric carbon dioxide and the huge glaciation associated that occurred during the Neoproterozoicperiod; (2) the shrinkage of large epicontinental Paratethys that covered a large part of Eastern Europe andWestern Asia and its impact on both monsoonal systems (African and Asian) since 40 Ma; and (3) the largeimpact of mountain range uplifts since Eocene both in Asia (Tibetan Plateau and Himalaya) and in Africa(buildup of the rift), on atmosphere and ocean dynamics. These studies not only allow for testing the abilityof Earth system models to capture long-term changes of Earth climate, but they also pinpoint the pivotal roletectonics played in shaping the long-term evolution of atmospheric CO2 and monsoon patterns.