Global and zonal tropospheric ozone variations from 2003-2011 as seen by SCIAMACHY

Abstract

An analysis of the tropospheric ozone (O3) columns (TOCs) derived from SCIAMACHY limb-nadir-matching (LNM) observations during 2003-2011, focusing on the zonal and global variations in TOC is described. The changes are derived using a multivariate linear regression model. TOC shows a change of -0.2 ± 0.4 % yr-1, 0.3 ± 0.4 % yr-1, 0.1 ± 0.5 % yr-1 and 0.1 ± 0.2 % yr-1, which are not statistically significant at the 2 σ level in the latitude bands 30-50°N, 20°S-0, 0-20°N and 50-30°S, respectively. Tropospheric O3 shows statistically significant increases over some regions of South Asia (1-3 % yr-1), the South American continent (up to 2 % yr-1), Alaska (up to 2 % yr-1) and around Congo in Africa (up to 2 % yr-1). Significant increase in TOC is derived from the continental outflows including those of Australia (up to 2 % yr-1), Eurasia (1-3 % yr-1) and the South America (up to 3 % yr-1). Significant decrease in TOC (up to -3 % yr-1) is observed over some regions of the continents of North America, Europe and South America. Over the Oceanic regions, significant decrease in TOC of about -2 % yr-1 is observed over the outflows of Europe and North America.