Vertical ozone and temperature distributions above Santa Maria, Brazil (1996–1998)

Abstract

Atmospheric soundings (troposphere and lower stratosphere) to measure ozone and meteorological profiles have been made at the Southern Space Observatory in Santa Maria, Brazil (29° S, 53° W) since 1996. In this paper a first analysis of the ozone profiles is presented from 1996 to 1998. Average ozone and temperature profiles are presented, and a comparison of total ozone obtained by integration of ozonesonde profiles with TOMS total ozone observations is performed. It is observed that ozone partial pressure has an average peak of about 128 μhPa, around 25 km. The minimum average temperature is about −70 °C around 16–17 km (tropopause). Total ozone integrated by soundings differs by about −6.63 ± 6.32% and −6.44 ± 4.73% in comparison with the total ozone measured by TOMS, using constant mixing ratio and McPeters climatology integration methods, respectively. Integrated tropospheric ozone represents about 12% (31 DU) of the total ozone, with minimum of 9% in March and maximum of 15% on October, while stratospheric ozone has a minimum in May and maximum in September. Around 50% of the soundings show a secondary ozone peak in the troposphere, mainly in November and January.