Spatio-temporal changes in daily extreme precipitation for the Lancang–Mekong River Basin

The Lancang–Mekong River Basin (LMRB) is one of the river basins most prone to floods and droughts induced by extreme precipitation (EP). Therefore, it is of great significance to characterize the spatio-temporal changes of EP in the LMRB. Based on the Multi-Source Weighted-Ensemble Precipitation dataset (MSWEP) Version 2.2 (V2.2) dataset from 1979 to 2016, all improved extreme precipitation indices (EPIs) at grid and national levels were computed and their changing trends were investigated by means of the trend-free pre-whitening Mann–Kendall significance test and the Sen’s slope; the rationality of the improved EPIs was discussed. The results revealed: (1) The improved EPIs performed better than the original ones in describing the spatio-temporal variations of EP across LMRB; (2) R95p, R99p, SDII-10, SDII-25, SDII-50, Rx1day, Rx3day, and Rx7day showed a significant decreasing trend ( p