Global rainstorm multi-attribute variation and its multiscale correlation with ENSO

Abstract

This research uses a variety of statistical methods to diagnose the multi-attribute time series characteristics of global rainstorms and its response to ENSO from the perspective of land-ocean differentiation. The results showed that: (1) The global, global land and global ocean rainstorm and their contribution rates showed an increasing trend from 1979 to 2016. While, the global, global land and global ocean total rainfall showed an decreasing trend. The global land total rainfall showed a distinct sectional change pattern, which first increased from 1979 to 2006 and then decreased from 2007 to 2016. The comparison between the rainstorm and the total rainfall in global land and ocean showed that the rainstorm tended to increase in both ocean and land regions from 1979 to 2016, while the weak intensity rainfall tends to decrease in the globe. (2) The global land and ocean rainstorm and total rainfall did not change consistently on multiple time scales from 1979 to 2016, but showed inverse phase or forward and lag phase correlation. Fourthly, compared with ENSO, global land (ocean) rainstorm changed earlier (lag) in high energy spectral region. Compared with ENSO changes in low energy spectral region, global land rainstorm changes were consistent or ahead of time, while global ocean rainstorm changes were mainly ahead of time compared with ENSO changes.