Climate modulation of summer rainstorm activity in eastern China based on the Tibetan Plateau spring heating

Abstract

Rainstorm intensity and frequency in eastern China are closely associated with the Asian summer monsoon, one of the largest and most pronounced circulation systems on Earth. Changes in monsoon strength are linked to mechanical and thermal forcing by the Tibetan Plateau (TP), which, as an extensive elevated landmass, forms a vast heat source that protrudes into the free atmosphere. However, the impact of TP heating variability on rainstorm behavior in eastern China remains unclear. By analyzing 50 years of climate data, significant interannual variability was identified in the occurrence of rainstorms (precipitation amounts of > 50 mm), with decreased trend in northern China and increased variability in southern China. Results show that these changes are closely related with the springtime TP heating, indicating that recent changes in rainstorm distributions in eastern China are consistent with interdecadal variability in TP thermal forcing.