Spatial and temporal variability of droughts in the Lancang River basin

Drought is one of the outstanding natural disasters of the Lancang River basin, studying on the variation characteristic of drought in the basin under the context of climate change is of great importance for scientific research and society. Using 46-year (1960-2005) daily precipitation records from 35 meteorological stations in and around the Langcang River basin, Southwest China, the Standardized Precipitation Index (SPI) was used to analyze the drought characteristics in the basin. By means of Principal Component Analysis (PCA) and K-means clustering (KMC) methods the study area was divided into 4 sub-regions, each sub-region had its own distinctive temporal evolution patterns of droughts. The wavelet analysis further revealed that there was a 3-6 year period of drought events for the entire basin. The results can be referenced by the decision-makers of government in future.