Midwinter Stratospheric Warmings in the Southern Hemisphere General Remarks and a Case Study

Abstract

Anomalously high stratospheric temperatures were measured by rocket sounding techniques over McMurdo, Antarctica, in midwinter 1963. Because of the importance of these observations in determining whether the Southern Hemispheric circulation exhibits midwinter stratospheric warming events similar to those in the Northern Hemisphere, data sources independent of the rocket soundings are examined. The data from the 15-? radiometer aboard TIROS VII, capable of determining the gross features of stratospheric temperature patterns, are used to check the rocket temperatures. Winds at McMurdo measured from rocketsonde techniques are used to determine the direction and magnitude of the 28-km thermal wind, which is compared with observed (rocket and radiosonde) temperatures. The TIROS VII radiometer data and the thermal wind and temperature gradient data are shown to be inconsistent with the high temperatures measured by the rocketsonde. Some suggestions are made as to the reasons for this apparent inconsistency. Finally, a plea is made for adoption of a standard terminology for stratospheric warmings. The conclusion is made that no major stratospheric warming has yet been satisfactorily observed in the Southern Hemisphere.