Data Assimilation Research Team Events / Media

Under the warmer climate projection, several models simulate that the annual number of the  tropical cyclone formation will decrease, but the intense tropical cyclone number will increase globally. The former may be related with the stabler condition of the atmosphere, and the latter may be related with the possible rapid intensification under the more humid condition near the surface.

To understand the former hypothesis, Arakawa and Schubert's cumulus parameterization method has been utilized to estimate all possible cloud types at each grid, using the ECMWF reanalysis dataset (ERA20C) from 1900 to 2010. The result shows that the tropical atmosphere is getting stabler and the cloud top hight of the deepest cloud type is getting lower. This may explain why the annual number of the tropical cyclone formation will decrease in future.