A quasitropical cyclone over the Black Sea: Observations and numerical simulation

摘要

A long-living mesoscale cyclone observed over the Black Sea in September 2005 was characterized by a high wind velocity (25 m/sec) and induced an abnormal lowering of the sea-surface temperature (by more than 10°C). We performed the numerical simulation of this cyclone by using the MM5 model and the data of global operative analysis. The evolution of the cyclone and its structure similar to the structure of a tropical cyclone are reproduced. The primary azimuthal and secondary radial circulations, the clear-sky eye with warm core at medium levels, and the eyewall with strong air updraft and intense convection and precipitation are well visible. The fluxes of sensible and latent heat on the sea surface played the key role in the initiation and development of this cyclone.