喀喇昆仑-喜马拉雅冰川的物质平衡在冰川学和全球变化研究中占有重要地位,但迄今整个区 域的冰川物质平衡特征仍知之甚少。本项目提出利用SAR干涉测量、卫星测高和卫星重力联合 监测物质平衡的研究方案,优势是:1)采用多源数据,将增加监测的空间覆盖、提高分辨率; 2)采用包括最新的卫星任务、观测模式数据(例,双站SAR、CryoSat-2 SAR干涉模式、GRACE Follow-On),将增加监测时间长度、同时提高监测结果精度;3)采用精细的数据处理和物 质平衡估计方法(例,多种测高方法联合分析、GRACE改进的质点法),确保结果的可靠性。主 要目标是,提供研究区10~20年典型冰川高分辨率和整个区域~200km分辨率物质平衡时间序列 结果,揭示物质平衡随区域、时间变化特征及其与西风带、印度季风的关系。研究结果有助于 评估冰川变化对东亚气候和比邻河流水资源的影响,对全球变化和海平面变化研究也具有重要 科学意义。
Mass balance of the glaciers in Karakoram and Himalaya Mountain Ranges plays an important role in glaciology and global change study. However, the characteristics of the glacier mass balance are still poorly known for the entire area. In the project, a synthetic methodology is proposed for estimating the mass balance by a joint application of Interferometric Synthetic Aperture Radar (InSAR), satellite altimetry and space-borne gravimetry, characterized by three advantages, 1)Data utilization from multiple sources will broaden the data coverage and improve the data resolution; 2)Data used will include those from some new satellite missions and the innovative modes (e.g., the bistatic SAR, CryoSat-2 SAR interferometric mode, GRACE Follow-On) extending the surveying time span and improving the accuracy of the mass balance estimate; 3)The refined data processing and the improved method of mass balance estimate will ensure the reliability of the results (e.g., the four approaches are applied together for satellite altimetry, an improved mascon method will be used for the inversion of mass balance based on GRACE gravity data). There are two primary objectives for this project. The first is to provide 10~20 years of time series of glacier mass balance with higher resolution for the typical glacier regions, and meso-scale resolution (~200km) for the entire area. The second is to uncover the spatio-temporal characteristics of the glacier mass balance, and the correlation to the magnitude of Indian monsoon and westerlies. The results from this project will be of great help to better understand the effects of glacier mass balance on the climate of East Asia, and the water resource of the adjacent rivers. In addition, they are also of scientific significance for the study of global change and sea level change.