Chemical ozone loss in the Arctic winter 1991–1992

S Tilmes,J M Russell,R J Salawitch,C R Webster,C C Camy-Peyret,R Müller,U Schmidt,H Oelhaf

doi:10.5194/acp-8-1897-2008

Abstract

Abstract. Chemical ozone loss in winter 1991–1992 is recalculated based on observations of the HALOE satellite instrument, Version 19, ER-2 aircraft measurements and balloon data. HALOE satellite observations are shown to be reliable in the lower stratosphere below 400 K, at altitudes where the measurements are most likely disturbed by the enhanced sulfate aerosol loading, as a result of the Mt.~Pinatubo eruption in June 1991. Significant chemical ozone loss (13–17 DU) is observed below 380 K from Kiruna balloon observations and HALOE satellite data between December 1991 and March 1992. For the two winters after the Mt. Pinatubo eruption, HALOE satellite observations show a stronger extent of chemical ozone loss towards lower altitudes compared to other Arctic winters between 1991 and 2003. In spite of already occurring deactivation of chlorine in March 1992, MIPAS-B and LPMA balloon observations indicate that chlorine was still activated at lower altitudes, consistent with observed chemical ozone loss occurring between February and March and April. Large chemical ozone loss of more than 70 DU in the Arctic winter 1991–1992 as calculated in earlier studies is corroborated here.

Highlights

The Arctic winter 1991–1992 was a climatological moderately warm winter
The amount of chemical ozone loss was quantified in several previous studies (e.g., Proffitt et al, 1993; Rex et al, 1998; Muller et al, 2001). These studies were based on different data sets: ER-2 aircraft measurements from the Airborne Arctic Stratospheric Expedition II (AASE-II) (Anderson et al, 1991; Toohey et al, 1993), data from the European Arctic Stratospheric Ozone Experiment (EASOE) (Pyle et al, 1994), namely observations from balloon-borne whole air samplers and ozone sondes
Profiles located within the polar vortex core show largest chemical ozone loss values, as observed by ER-2 during January and February and by Halogen Occultation Experiment (HALOE) between February and April

Summary

Introduction

The Arctic winter 1991–1992 was a climatological moderately warm winter. For this winter, chemical processes in the polar vortex were strongly influenced by the enhanced burden of sulfate aerosols after the eruption of Mt. The amount of chemical ozone loss was quantified in several previous studies (e.g., Proffitt et al, 1993; Rex et al, 1998; Muller et al, 2001). These studies were based on different data sets: ER-2 aircraft measurements from the Airborne Arctic Stratospheric Expedition II (AASE-II) (Anderson et al, 1991; Toohey et al, 1993), data from the European Arctic Stratospheric Ozone Experiment (EASOE) (Pyle et al, 1994), namely observations from balloon-borne whole air samplers and ozone sondes. Ozone loss was derived using satellite observations from the Halogen Occultation Experiment (HALOE) (Russell et al, 1993) and from the microwave limb sounder (MLS) measurements (Tilmes et al, 2004; Manney et al, 2003), both aboard the UARS satellite

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