Trends in the Stratosphere – a Re-Assessment

Abstract

A re-examination of the data of Labitzke &. van Loon (Adv. Space Res. I I ,(3)21' (3)30, 1991) indicates that the geopotential heights and temperatures in the stfatosphere forthe last 25 years show distinct trends when 4-point running averages and 1 ¡-yearty running averages are examined. Trends are somewhat different at different altitudes and for different seasons and latitudes. In general, geopotential heights show downtrends up to 1975 and an upward trend from 1975,onwards up to date. Temperatures show'a negligible or downward trend up to 1975 and upward trend during 1975-79, and a downward trend from 1979 up to date air reverse to that of surface air temperature.