Effect of East－Asian Monsoon on Drought Climate of Northwest China

Wavelet technique is used to analyses the variability of East－Asian monsoon in recent 50 years. Correlationanalysis method is used to investigate the impact of the East－Asian winter monsoon and summer monsoon impact on the temperature and precipitation of Northwest China. The results show that the influence of East－Asian monsoon on the drought formation of Northwest China is significant. The surface temperature of East－Asian continent and Pacific SSTpreceding the East－Asian winter and summer monsoonare studied, the result suggests that the East－Asian monsoon intensity is closely related to the precedingthermal status of East－Asian continent and Pacific SST, the bigger the temperature gradient between continent and ocean, the stronger the East－Asian monsoon, and vice versa. On the contrary, monsoon intensity can also influence the thermal status of the continent and ocean.