H. E. Scheel

TL;DR: The Influence of Stratosphere-Troposphere Exchange in a Changing Climate on Atmospheric Transport and Oxidation Capacity (STACCATO), recently funded by the European Union, provides a review of stratosphere-troposphere exchange (STE), with a focus on processes in the extratropics.

TL;DR: Tropospheric ozone changes are investigated using a selected network of surface and ozonesonde sites to give a broad geographic picture of long-term variations as discussed by the authors, and three time series of � 20 years in length agree in showing increases that are strongest in the austral spring (August-October). Profile measurements show this increase extending through the mid troposphere but not into the highest levels of the troposphere.

TL;DR: In this article, changes in baseline (here understood as representative of continental to hemispheric scales) tropospheric O3 concentrations that have occurred at northern midlatitudes over the past six decades are quantified from available measurement records with the goal of providing benchmarks to which retrospective model calculations of the global O3 distribution can be compared.

TL;DR: In this article, the authors analyzed long-term (20-40 years) Tropospheric ozone (O3) time series obtained from surface and ozonesonde observations to assess possible changes with time through 2010.

TL;DR: The authors presented an approach for quantitative comparisons of model results with measurements for seasonally averaged tropospheric ozone (O3) concentrations, concluding that only limited confidence can be placed on estimates of present-day radiative forcing of ozone derived from modeled historic concentration changes and on predicted future O3 concentrations.