The strengthening East Asia summer monsoon since the early 1990s

Previous studies have documented a weakening tendency of the East Asian summer monsoon (EASM) since the end of the 1970s. In this study, we report that the EASM has been recovering since the early 1990s, although its strength is still less than in previous decades (averaged over the period 1965-1980). Following the recovery of the EASM, there has been a tendency in the last decade toward northward-moving rainbands and excessive rainfall in the Huaihe River valley (110A degrees-120A degrees E, 30A degrees-35A degrees N). There is evidence suggesting that the strengthening EASM since the early 1990s is linked to interdecadal change of land-sea thermal contrast.