Mechanisms of Seasonal March of Precipitation over Maritime Continent

Maritime continent is the most important area in the climate study. Understanding the mechanisms work over this region can be a good information for the climate research community. Present work focuses on the relationship among maritime continent precipitation, intertropical convergence zone (ITCZ) migration and the Asian monsoon. Observational study shows assymmetric pattern of the precipitation over maritime continent in the boreal summer and winter. The ITCZ jumps from the southern hemisphere to the northern hemisphere in summer coinciding with the activity of Asian monsoon. As a result, whole parts of maritime continent experiences dry condition in summer. Through some sensitive experiments of the global circulation model (GCM), the mechanisms driving Asia monsoon is done. It is found that sea surface temperature (SST) and land-surface temperature are important to control the Asian monsoon in the different way. The SST mainly controls the jump of the ITCZ between the southern and northern hemispheres. On the other hand, the land-sea heat contrast activates the Asian summer monsoon, and shifts the ITCZ northward away from maritime continent.