Longitudinal variations of temperature and ozone profiles observed by MIPAS during the Antarctic stratosphere sudden warming of 2002

Authors


Abstract

[1] The temperature and ozone volume mixing ratio (VMR) profiles measured by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on ENVISAT are used to study the unusual Antarctic major stratospheric warming of 2002. The observed zonal mean temperatures show rapid poleward increase and remarkable reversal of the latitudinal gradients at 35 km or below in several days. The highest temperature increase is of 50 K or more. The zonal mean ozone VMRs also increase poleward and have maximum values of 7 ppmv in a wide region between 20 and 40 km at latitudes south of 40°S. Temperature amplitudes of zonal wave number 1 to 3 exhibit a double-peaked structure with peaks near 25 km and 35 km. The ozone waves in the lower stratosphere are generally in phase with the corresponding temperature waves. At the onset of the warming, the wave 1 amplitudes drastically increase at 60°S–80°S, reaching maxima of ∼20 K for the temperature and ∼2 ppmv for the ozone VMR. Significant wave 3 amplitudes are also observed with maximum of 14–18 K and 1–1.5 ppmv for temperature and ozone VMR, respectively. The wave 3 amplitudes are larger than those of wave 2 by nearly a factor of 2 immediately before and after the polar vortex split. The large-amplitude wave 1 and 3 disturbances break down in 1 or 2 days, and the wave 2 variations are enhanced and attain amplitudes comparable to those of wave 1 and 3, resulting in an apparent wave 2 warming event. These results are consistent with other observations and suggest the importance of wave 3 forcing in the major warming.