Tittle:Seasonal Cycles of High Mountain Asia Glacier Surface Elevation Detected by ICESat-2
Abstract:High Mountain Asia (HMA) glaciers are a key component of mountain hydrology and their seasonal ablation contributes significantly to the annual runoff of several large river systems that protect large populations from water stress. However, the seasonal cycle of glacial change remains unclear. Recent NASA's Ice, Cloud, and Land Elevation Satellite (ICESat-2) provides an opportunity to survey changes in the glacier surface elevation in unprecedented detail. Here, we used a new approach—which is based on a developed elevation bin cluster with a sliding filter and an iterative recovery method—to obtain the complete seasonal cycle of glacier thickness changes in HMA. We generally identified three types of glaciers: (a) glaciers in the westerly dominant area (WDA) (b) glaciers in the Indian monsoon area (IMA), and (c) glaciers in the transition area (TA). The peak thickness values for the IMA, WDA, and TA glaciers occur in February, May, and June, respectively. Most glaciers in WDA and IMA show a strong seasonal cycle with variations of more than 2 m, while the TA glaciers are mainly characterized by weak changes of up to 1 m. Overall, our results show that the glaciers can provide 67–138 Gt of meltwater per year to downstream. These results provide crucial information for the calibration of models that project glacier response to climate change and simulate the downstream water availability. Our methodology facilitates the application of ICESat-2 to seasonal tracking of glacier variability in global alpine areas.
Citation:Wang, Q., & Sun, W. (2022). Seasonal cycles of High Mountain Asia glacier surface elevation detected by ICESat-2. Journal of Geophysical Research: Atmospheres, 127, e2022JD037501.
