A madden-julian oscillation-triggered record ozone minimum over the tibetan plateau in december 2003 and its association with stratospheric "low-ozone pockets"

Abstract

A record minimum in total column ozone over the Tibetan Plateau in December 2003 is analyzed using both satellite observations and a chemical transport model (MOZART-3). Ozone profiles observed by the MIPAS and GOMOS over the ozone minimum region (25°-35°N, 85°-HO0E) show pronounced ozone reduction in both the upper troposphere and lower stratosphere (UTLS) and the middle stratosphere regions. MOZART-3 simulation indicates that ozone reduction in the UTLS region is generally caused by uplift of the local tropopause and northward transport of tropical ozone-poor air associated with an anomalous anticyclone in the upper troposphere. MIPAS observation suggests that the displacement of "low-ozone pockets" is responsible for ozone decline in the middle-stratospheric region and contributes to 29-46% of the total column ozone reduction. Further analysis shows that the upper-tropospheric anticyclonic anomaly is closely associated with the Rossby-wave triggered by the eastward propagating Madden-Julian Oscillation convective heating. Copyright 2009 by the American Geophysical Union.