青藏高原及周边大气水循环过程多尺度变化特征及其天气气候效应

Tibetan Plateau plays an essential role to the Asia and even global weather and climate system for both energy balance and hydrological cycle. However, our knowledge regarding the characteristics, causes and impacts of changes of multi-scale atmospheric hydrological cycle over TP is very limited and highly demanded. Using multiple data sources from satellite-, aircraft-, and ground-based observations along with the reanalysis data, such as Himawari-8, MODIS, CloudSat cloud observations, TRMM and GPM precipitation observations, CERES radiation observations, ECMWF weather variable data, and site observations, this study investigates the following subjects. (1) We analyze the characteristics and spatial-temporal variation of atmospheric hydrological variables such as clouds, precipitation and water vapor over Tibetan Plateau and nearby regions. (2) Using clustering method and model simulations, we investigate the responses of clouds, precipitation, and atmospheric circulation to transported aerosols from Asia, particularly from India, along with the response to the aerosol radiative effects. (3) With both observations and model simulations, this study examines the impacts of hydrological circulation changes over Tibetan Plateau to the weather and climate around this region. This study will improve our understanding of the characteristics and mechanisms of atmospheric hydrological changes over Tibetan Plateau and nearby regions, along with their impacts to regional weather and climate, which is very important for future improvement of cloud-related model schemes, helping enhance the performance of both weather and climate models.

青藏高原在东亚乃至全球能量平衡和水循环中均扮演着至关重要的作用，然而对于这一地区多尺度大气水循环时空变化特征、成因及其影响的理解相对缺乏，亟待提高。本项目拟利用卫星、飞机和地面多源探测和再分析资料，包括葵花8、MODIS、CloudSat卫星云资料，TRMM和GPM卫星降水观测资料，CERES卫星辐射观测，ECMWF再分析资料，站点观测资料等，（1）分析高原及其周边多尺度云、降水、水汽等大气水循环要素的物理特征及其时空变化；（2）利用聚类分析和模式实验，理解东亚（主要印度）污染对该区域水循环特征（云、降水和环流）及其辐射效应的影响；（3）利用观测统计和模式模拟，研究区域水循环变化对东亚区域天气和气候的影响。本项目将促进对青藏高原水循环时空变化特征、机理及其天气和气候影响的认识，有助于进一步完善青藏高原区域水循环关键要素的参数化方案，提高区域天气和气候模式模拟能力。

青藏高原在东亚乃至全球能量平衡和水循环中均扮演着至关重要的作用，然而对于这一地区多尺度大气水循环时空变化特征、成因及其影响的理解相对缺乏，亟待提高。本项目利用卫星、飞机和地面多源探测和再分析资料，包括葵花8、MODIS、CloudSat和Calipso卫星云资料，TRMM和GPM卫星降水观测资料，CERES卫星辐射观测，ECMWF再分析资料，地面站点观测资料等，研发了基于静止卫星、适合青藏高原复杂下垫面地形的昼夜连续云宏观特征遥感反演方法；构建了基于静止卫星、更为精确的青藏高原云微观特征遥感反演方法，形成了冰云遥感反演产品数据集；构建了适合复杂下垫面的气溶胶光学厚度机器学习反演模型；构建了地面下行短波辐射计算模型；揭示了高原及其周边多尺度云、降水、水汽等大气水循环要素的物理特征、热动力特征及其时空变化；利用聚类分析和模式实验，揭示了青藏高原气溶胶特征和来源，尤其是沙尘来源问题；揭示了青藏高原云和辐射对周边输送气溶胶的响应及其机理，厘清了气溶胶对云微观特征、云发展演变和辐射强迫的影响；揭示了青藏高原气溶胶影响下云和辐射改变所引起的天气和气候效应，尤其是云降水和辐射能量平衡的变化。本项目促进了对青藏高原水循环时空变化特征、机理及其天气和气候影响的认识，有助于进一步完善青藏高原区域水循环关键要素的参数化方案，提高区域天气和气候模式模拟能力。项目形成了青藏高原及周边 Himawara-8 冰云遥感反演产品 1 份，产品包含1年冰云遥感特征，时间分辨率为1小时；项目已发表学术论⽂ 57篇，其中 SCI 论⽂ 53 篇，包括第一和第二标注论文28篇；培养了毕业博士生10 ⼈，硕⼠生 15 ⼈；项目骨干成员2位获得国家杰青，2位由中级职称晋升高级职称。