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°–110°E) 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.