Fig. 6: Relationship of sea surface temperature (SST) and tropical cyclone (TC) passage frequency in East Asia during the mature boreal autumn.

a Global composite difference map of SST between Period 2 (1998−2019) and Period 1 (1981−1997), respectively. b Spatial correlation map of TC passage frequency and SST. The black solid (dotted) boxes indicate the locations of indicated climate index (Interdecadal Pacific Oscillation regions). In a, b, the black dots indicate significant difference and correlation at p < 0.05, respectively. Significance is tested using student’s t-test statistic with two-tailed distribution.