Quantifying the tropospheric ozone radiative effect and its temporal evolution in the satellite era

Abstract

Abstract. Using state-of-the-art satellite ozone profile products, and a chemical transport model, we provide an updated estimate of the tropospheric ozone radiative effect (TO3RE) and observational constraint on its variability over the decade 2008–2017. Previous studies have shown the short-term (i.e. a few years) globally weighted average TO3RE to be 1.17 ± 0.03 W m−2. However, from our analysis, using decadal (2008–2017) ozone profile datasets from the Infrared Atmospheric Sounding Interferometer, average TO3RE ranges between 1.21 and 1.26 W m−2. Over this decade, the modelled and observational TO3RE linear trends show a negligible change (e.g.  ± 0.1 % yr−1). Two model sensitivity experiments fixing emissions and meteorology to 1 year (i.e. start year – 2008) show that temporal changes in ozone precursor emissions (increasing contribution) and meteorological factors (decreasing contribution) have counteracting tendencies, leading to a negligible globally weighted average TO3RE trend.