To what extent can the 2002 Antarctic major stratospheric warming be explained by horizontal advection of the vortex from the pole?

• Published in: Meteorology and atmospheric physics Vol. 90; no. 3-4; pp. 165 - 177
• Main Authors: SIEGMUND, P, VAN VELTHOVEN, P
• Format: Journal Article
• Language: English
• Published: Wien Springer 01.10.2005; New York, NY Springer Nature B.V
• Subjects: Advection; Air flow; Atmosphere; Atmospheric models; Earth, ocean, space; Energy equation; Exact sciences and technology; External geophysics; Physics of the high neutral atmosphere; Stratosphere; Temperature; Tides, waves, convection, winds, turbulence; Wind; South Pole; Antarctica; Antarctic region; advection; Temperature distribution; models; Polar vortex; Wind field; Energy equation; Zonal wind; Arctic stratospheric vortex; polar regions; Stratospheric warming; thermodynamic properties; stratosphere
• ISSN: 0177-7971; 1436-5065
• DOI: 10.1007/s00703-004-0085-8

The importance of horizontal and vertical advection of temperature for the Antarctic major stratospheric warming in September 2002 has been investigated, by applying the thermodynamic energy equation to ECMWF temperature and wind data. The analysis, which is carried out for the one-week period 19-26 September, shows that the large temperature increase in this period in the polar stratosphere is mainly due to horizontal advection of temperature. In addition, it has been investigated to what extent the observed temperature increase, as well as the change in the zonal wind, can be simulated with a simple conceptual model of a moving polar vortex. The model consists of a horizontal, circular vortex whose centre moves with constant meridional velocity off from the South Pole. The temperature and zonal wind fields are prescribed, stationary and zonally symmetric (relative to the vortex centre). Despite its simplicity, the model simulates several important aspects of the observations, such as the zonal-mean temperature increase and zonal-mean zonal wind reversal poleward of 60 degrees, and the zonal-mean temperature decrease at middle latitudes. [PUBLICATION ABSTRACT]