Variation In SST Over The Marginal Seas Of China In Recent 50 Years And Its Relationship With Precipitation In China

In terms of HadISST, OAflux datasets and monthly precipitation at 160 stations of China during 1962～2011 and using statistical methods, variations in sea surface temperature (SST) over the marginal seas of China (Bohai, Yellow, East China and South China Seas) and their possible causes are first investigated, then the relationship between SST over the marginal seas and precipitation over mainland of China is analyzed, finally a global general circulation model (CAM5.1) is also employed to simulate the effect of the warming over the marginal seas of China on precipitation in China. The main results are as follows:(1) Results show that the SST over the marginal seas has exhibited significant warming trends in the past 50 years. The warming trends are different in each season, with the max warming trends in winter. Changes in sea surface heat fluxes play a restrictive role in warming the SST over the marginal seas, which act to damp the long-term warming of the winter SST in marginal seas.Changes in sea surface temperature horizontal advection act to promote the long-term warming of the SST in marginal seas, indicating that ocean dynamical processes are the main causes of the SST warming.(2)The warming changes in sea surface temperature (SST) over the marginal seas of China not only have long-term changes but also have a significant interannual variability. A pronounced increase in winter precipitation over the middle and lower reaches of the Yangtze River is closely related to the long-term changes of SST over the marginal seas of China in winter. A global general circulation model (CAM5.1)is also employed to simulate the effect of the long-term warming over the marginal seas of China on precipitation in China. It is found that simulated results are consistent with observations, which further confirms the impact of this long-term change in SST over the marginal seas of China on precipitation in East China in winter.(3)Long-term changes in SST over the marginal seas of China in spring is in good correlation with the spring precipitation in China. A pronounced increase in spring precipitation over the southeast coast of China is closely related to the long-term trends of this spring SST warming over the marginal seas. Long-term changes in summer SST over the marginal seas of China is also in good correlation with the summer precipitation in China. A pronounced increase in summer precipitation over the middle and lower reaches of the Yangtze River is closely related to the long-term trends of SST warming in summer over the marginal seas.(4) The relationship between interannual changes in SST(winter, spring and summer) over the marginal seas with the precipitation in China and lower troposphere circulation is almost consistent with the results of long-term changes, indicating that in different time scales(long-term changes or interannual changes),the relationship between changes in SST over the marginal seas with the precipitation is almost the same.