Estimation of seasonal precipitation memory curves for major rivers in the Tibetan Plateau based on GRACE satellites data

Abstract

Study region: River basins in the Tibetan Plateau, including the Yarlung Zangbo River (YZR) basin, the Salween River (SWR) basin, the Lancang River (LCR) basin, the Yangtze River (YTR) basin, the Yellow River (YLR) basin, and the Tarim River (TRM) basin. Study focus: In recent years, the concept of seasonal catchment memory has emerged as a pivotal element in the field of hydrological science. Precipitation memory curve (PMC) is a good method to describe seasonal precipitation memory process, which is the key function connecting precipitation and terrestrial water storage change (TWSC). The model simulated TWSC with precipitation is proposed based on PMC. According to the performance of the model, this study investigates optimal curve functions to describe seasonal catchment memory in the Tibetan Plateau. New hydrological insights for the region: It is found that in most basins, the shape of PMC is consistent with the Boussinesq function or Maillet function. In the SWR basin, PMC varies between warm season and cold season. However, due to relatively less precipitation in the cold season compared to the warm season, the segmented-representation PMC has only a slight improvement on the TWSC simulation. In the TRM basin, the temperature-index method can improve the performance of the model. The PMC of the TRM basin during the warm season exhibits a short duration of precipitation memory of approximately three months.

Keywords

• Seasonal catchment memory
• Terrestrial water storage
• Tibetan Plateau
• Precipitation memory curve