Recent climate models consistently project a decreasing trend of global tropical cyclone (TC) frequency in the future due to global warming. In our recent 228 year long simulations from 1872 to 2099, a decreasing trend of global TC frequency is found not only in the future but also in the past during the twentieth century. The decreasing trend of TC frequency is closely related to a decreasing trend of upward mass flux in the tropics, and it is in turn closely related to an increasing trend of dry static stability. Both decreasing trend of upward mass flux and increasing trend of dry static stability are simulated in all climate models. However, some observational studies indicated that the dry static stability was increasing at much smaller rate than the climate models or even decreasing during the last 30 years. In this paper, we explore possible causes of this apparent discrepancy between the observations and models by comparing the 228 year simulations with several reanalysis data. It is found that the difference between the model and reanalysis is within the uncertainties among the different reanalysis data.

Date Published: 8 November 2012
PDF: 6 pages
Proc. SPIE 8529, Remote Sensing and Modeling of the Atmosphere, Oceans, and Interactions IV, 852904 (8 November 2012); doi: 10.1117/12.977948

Published in SPIE Proceedings Vol. 8529:
Remote Sensing and Modeling of the Atmosphere, Oceans, and Interactions IV
Michio Kawamiya; Tiruvalam N. Krishnamurti; Shamil Maksyutov, Editor(s)