Fig. 5

The linear trend of a FMA-accumulated precipitation (unit: mm day−1 decade−1) and b FMA-accumulated PET (unit: decade−1). Significant values exceeding the 0.1 and 0.05 significance levels are marked by gray and black dots, respectively. The contributions of c P and d PET to the linear trend of April SPEI-3 (unit: %) are also calculated, but only the regions with the linear trend of April SPEI-3 exceeding the 0.1 significance level are shown