Seasonal variations of Asian monsoon observed from space

Water is transported between ocean and land in the annual time scale through monsoons. We have developed a method to derive the integrated moisture transport from wind measured by QuikSCAT representing surface stress, and cloud-drift winds at 850 mb representing free stream velocity, and precipitable water, based on support vector regression. Large-scale rainfall over the Asian continent is largely affected by monsoons, the seasonal change of winds caused by the reversal of land-ocean temperature gradient. Over land, the consequences of monsoon vagary are well observed, but the breeding ground over ocean has not been sufficiently monitored until recently by spacebased sensors. Ocean's role in the seasonal monsoon rainfall over the Asian continent is revealed using recent high-resolution spacebased data. The balance of continental rainfall with moisture advected from the ocean is discussed. The feedback of soil moisture changes to the onset and development of Asian monsoon is also examined.