Lake dynamics in Tibetan Plateau during 1990-2020 and exploratory factor analyses using Google Earth Engine.

Abstract

Tibetan Plateau (TP) lakes are crucial water resources for many countries, and the region is sensitive to climate change, so the TP lakes' dynamics have always been the focus of TP research. Given the vastness of the TP, the diversity of topography, geomorphology, and meteorological features, and the significant disparities in precipitation between river basins, it is vital to examine lake dynamics and influencing variables from the basin's perspective. Based on Landsat imageries and supported by Google Earth Engine, lakes were mapped from 1990 to 2020. Results show that the TP lake's number and area have increased significantly in recent 30years except for a noticeable shrinkage from 1990 to 1995 and a slight decrease from 2013 to 2015. The lake area in the endorheic region basin area has grown obviously, with the most significant dynamics in the Qiangtang Basin, where the lake's number and total area have increased by about 30% over the 30years. In contrast, the lake areas in the outflow region basins were relatively stable. The dynamics were obviously affected by temperature, but the influencing factors and degree of influence on different river basins vary. The lake area in the Amu Dayra Basin and the Yellow Basin was more closely related to precipitation, and the lake area in the Hexi Basin was more related to temperature. The results provide a comprehensive understanding of lake spatial-temporal dynamics in the Tibetan Plateau and its river basins and a reference for studying lake long time series.