Spatio-temporal variation of annual precipitation in China and its response to ENSO

The results showed that the precipitation in the study area was mainly in a downward trend before the mid-1930s, and then turned upward. In the 1950s, the precipitation generally showed a distribution of rising in the west and falling in the east, and this trend continued until the early 21st century. By 2007, except for the central part of the Continental Basin, the overall trend was mainly upward. In this study, 65 El Nino/La Nina Southern Oscillation (ENSO) events were identified, including 24 El Nino events and 41 La Nina events. The precipitation was generally less when ENSO occurred. However, there were differences in the type and intensity of the event. For example, El Nino had a greater impact on precipitation than La Nina did, and extremely strong or strong El Nino/La Nina events had a more significant impact than moderate, weak, or extremely weak ones. The correlation between precipitation and El Nino or La Nina events had some similarities and differences. For example, precipitation was mainly negatively correlated with El Nino and La Nina at the same time, and both correlations were proportional to intensity, but the correlation between precipitation and El Nino was significantly stronger than that of La Nina.