青藏高原气候系统变化及其对东亚区域的影响与机制研究进展

青藏高原地区特殊的大气圈、水圈、冰冻圈、生物圈等多圈层相互作用过程及其变化,不仅对青藏高原及其周边地区的气候格局和变化有重要影响,而且对东亚、北半球乃至全球的环流形势和异常产生深远影响。为此,全球变化研究重大科学研究计划于2010年9月启动了"青藏高原气候系统变化及其对东亚区域的影响与机制研究"项目,旨在开展青藏高原环境、地表过程、生态系统对全球变化的响应及其对周边地区人类生存环境影响的综合交叉研究,以揭示青藏高原气候系统变化及其对东亚区域的影响机制,提出前瞻性的应对气候变化与异常的策略,减少其导致的区域自然灾害的损失。项目实施近3年来,开展了青藏高原首次"星—机—地"综合立体协同观测试验和大规模地气相互作用综合观测试验。在遥感结合地面观测估算青藏高原地表特征参数和能量通量方法,高原地区上对流层和下平流层结构,高原季风与东亚季风和南亚季风之间的内在联系,中国及青藏高原地区太阳辐射和风速的年代际变化趋势,青藏高原春季感热源减弱及其对亚洲夏季风和中国东部降水的影响,以及极高海拔地区土地覆被格局等方面取得了一些突出进展。

Study Progresses of the Tibet Plateau Climate System Change and Mechanism of its Impact on East Asia

The interaction between atmosphere, hydrosphere, cryosphere and biosphere of the Tibetan Plateau (TP) significantly affects not only climate pattern and climate change in local and surrounding area, but also the Asian monsoon process and the global atmospheric circulation. The study of the “Tibet Plateau climate system change and mechanism of its impact on East Asia”, a project of the National Key Scientific Research Program of China for Global Change Study, was initiated in September of 2010. It aimed at performing integrated research on the Tibetan Plateau climate system responding to global change and its impact on surrounding areas, collaborating on major scientific issues to achieve breakthrough in scientific research on the Tibet Plateau climate system change and mechanism of its impact on East Asia, proposing prospective strategy coping with abnormal climate change to reduce regional natural disaster losses. A simultaneous and coordinated experiment of air borne remote sensing and ground based observation was carried out in TP for the first time. And a series of research results have been achieved in the past three years of project implementation. The results include determination of regional distributions and seasonal variations of land surface heat fluxes in whole TP region, behavior of the tropopause folding events over the west TP, definition of plateau monsoon and its association with general circulation anomalies, decrements of solar radiation and wind speed across China and TP area in recent decades and their possible causes, weaken trend of sensible heat source in the spring over TP and its impact on the Asian summer monsoon, and classification of land cover in high altitude region of Mount Qomolangma, etc.