Inhaltszusammenfassung

Numerical simulations of Antarctic mesocyclones (MCs) have been carried out with the hydrostatic limited-area model of the Norwegian Meteorological Institute (DNMI). The governing mechanisms in meso-scale cyclogenesis and the three-dimensional structure of three Antarctic coastal MC events are investigated, representing two different types of mesocyclogenesis. Two topographically forced MCs are studied, occurring on 8 February 1990 (Case 1) and on 19 January 1990 (Case 2) over the ice-free pa...Numerical simulations of Antarctic mesocyclones (MCs) have been carried out with the hydrostatic limited-area model of the Norwegian Meteorological Institute (DNMI). The governing mechanisms in meso-scale cyclogenesis and the three-dimensional structure of three Antarctic coastal MC events are investigated, representing two different types of mesocyclogenesis. Two topographically forced MCs are studied, occurring on 8 February 1990 (Case 1) and on 19 January 1990 (Case 2) over the ice-free part of the eastern Weddell Sea with horizontal scales of 200-300 km and lifetimes of around 12 h. For these cases, the synoptic environment in combination with the katabatic wind system is found to be the dominating forcing on the MC development and structure, and the generation of cyclonic vorticity by vortex stretching is found to be of great importance. In contrast to the orographically forced cases, which are of a rather small scale, a MC occurring from 3-6 January 1986 (Case 3) represents the development of a MC with a horizontal scale of about 1000 km being forced by upper-level cyclonic vorticity advection» weiterlesen» einklappen

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DDC Sachgruppe:
Naturwissenschaften