Chemical ozone loss and chlorine activation in the Antarctic winters of 2013–2020

oleh: R. Roy, R. Roy, P. Kumar, J. Kuttippurath, F. Lefevre

Format: Article
Diterbitkan: Copernicus Publications 2024-02-01

Deskripsi

<p>The annual formation of an ozone hole in the austral spring has regional and global climate implications. The Antarctic ozone hole has already changed the precipitation, temperature and atmospheric circulation patterns, and thus the surface climate of many regions in the Southern Hemisphere (SH). Therefore, the study of ozone loss variability is important to assess its consequential effects on the climate and public health. Our study uses satellite observations from the Microwave Limb Sounder on Aura and the passive-tracer method to quantify the ozone loss for the past 8 years (2013–2020) in the Antarctic. We observe the highest ozone loss (about 3.5 ppmv) in 2020, owing to the high chlorine activation (about 2.2 ppbv), steady polar vortex, and huge expanses of polar stratospheric clouds (PSCs) (<span class="inline-formula">12.6×10<sup>6</sup></span> km<span class="inline-formula"><sup>2</sup></span>) in the winter. The spring of 2019 also showed a high ozone loss, although the year had a rare minor warming in mid-September. The chlorine activation in 2015 (1.9 ppbv) was the weakest, and the wave forcing from the lower latitudes was very high in 2017 (up to <span class="inline-formula">−</span>60 km s<span class="inline-formula"><sup>−1</sup></span>). The analysis shows significant interannual variability in the Antarctic ozone as compared to the immediate previous decade (2000–2010). The study helps to understand the role of dynamics and chemistry in the interannual variability of ozone depletion over the years.</p>