Severe Arctic ozone loss in the winter 2004/2005: observations from ACE‐FTS

Abstract

The severe Arctic ozone reduction in the winter 2004/2005 is analyzed using ACE‐FTS observations and four different analysis techniques: correlations between ozone and long‐lived tracers (adjusted to account for mixing), an artificial tracer correlation method, a profile‐descent technique, and the empirical relationship between ozone loss and potential PSC volume. The average maximum ozone loss was about 2.1 ppmv at 475 K–500 K (∼18 km–20 km). Over 60% of the ozone between 425 K–475 K (∼16 km–18 km) was destroyed. The average total column ozone loss was 119 DU, ∼20–30 DU larger than the largest previously observed Arctic ozone loss in the winter 1999/2000.