基于卫星遥感的青藏高原湖泊水系统要素动态监测及其对气候变化的响应

The Tibetan Plateau plays a critical role in the global climate change research for its geographical speciality. The changing lake water system in the Tibetan Plateau, which includes changes in water balance, heat balance and bio-chemical processes, is regarded as a sensitive indicator of climate change. However, owing to limited ground observation records, the response of lake water system to climate change in the plateau is largely unknown, especially on the aspect of water environment. To improve the monitoring and assessment capacity for both lake system water cycle and water environment in the Tibetan Plateau, this project intends to (1) develop novel inversion algorithm for critical water system factors like (chlorophyll a、turbidity、water color) using the remote sensed data, especially the most recent available high resolution data. The remote sensed data like lake water level will help to calibrate and validate water-heat balance model of the lake system; (2) to investigate the relationship between water environment factors and water cycle components, which reflects the environmental consequence of hydrological change; (3) to assess the impacts of climate change on the lake system in terms of water balance, heat balance and the corresponding water environment by combining hydrological simulation and the statistical model established between water environment and the driving factors. The project is expected to fill the research gaps on spatial-temporal water environment change in the Tibetan Plateau, as well provides scientific reference and technical support of regional water protection and exploitation.

青藏高原是全球变化研究的重点区域之一。青藏高原湖泊水系统的变化，包括水量平衡、能量平衡以及生物化学过程，对气候变化都有敏感的响应。为加强青藏高原区域水循环与水环境的监控，把握高原水系统变化的总体态势，探索其相应的驱动机制与主要的驱动因子，本项目拟利用多源多时空尺度遥感数据及产品，围绕水资源与水环境保护，通过改进、发展遥感反演算法，实现区域水循环与水环境关键要素的动态监测，并与水文分析模拟手段相结合，揭示青藏高原主要湖泊水循环与水环境的变化规律，寻找湖泊水循环与水环境变化的主要驱动因子，定量评估湖泊水系统对气候变化的响应，填补青藏高原大范围湖泊水环境时空变化研究的空白，为区域水体的保护与开发提供科学参考与技术支撑。

青藏高原是全球变化研究的重点区域之一。青藏高原的水热平衡也是全球变化研究的热点和难点。受地面观测资料缺乏的限制，青藏高原湖泊水系统（特别是水环境）的变化与及其对气候变化的响应机制等方面研究还较为薄弱。项目紧密围绕青藏高原湖泊的水量平衡、能量平衡及生物化学过程，将遥感监测与水文模拟相结合，在青藏高原湖泊关键水系统要素动态遥感监测、模式模拟及其对气候变化的响应研究等方面取得了主要进展。首先，构建了长时序湖泊水系统要素（湖面温度、湖泊水量变化和湖冰物候等）时间序列数据及产品；然后，定量评价了遥感在水系统要素监测中的不确定性和对水文模拟的影响，基于水量平衡及能量平衡模拟，揭示了青藏高原湖泊水系统要素的时空变化规律及主要驱动因子；最后，分析了湖泊流域水系统对气候变化的响应特征。这将为气候变化背景下青藏高原水资源的合理评价、开发、利用和规划提供可靠的科学数据和理论依据。