The extratropical upper troposphere and lower stratosphere (Ex‐UTLS) is a transition region
between the stratosphere and the troposphere. The Ex‐UTLS includes the tropopause, a …

We discuss and evaluate the representation of atmospheric chemistry in the global
Community Atmosphere Model (CAM) version 4, the atmospheric component of the …

In this study we use the ERA-Interim reanalysis data set from the European Centre for
Medium-Range Weather Forecasts (ECMWF) and a refined version of a previously …

The published literature debates the extent to which naturally occurring stratospheric ozone
intrusions reach the surface and contribute to exceedances of the US National Ambient Air …

Now that stratospheric ozone depletion has been controlled by the Montreal Protocol,
interest has turned to the effects of climate change on the ozone layer,. Climate models …

Methane and ethane are the most abundant hydrocarbons in the atmosphere and they affect
both atmospheric chemistry and climate. Both gases are emitted from fossil fuels and …

We use ozone observations from sondes, regular aircraft, and alpine surface sites in a self‐
consistent analysis to determine robust changes in the time evolution of ozone over Europe …

This study investigates changes in stratosphere‐troposphere exchange (STE) of air masses
and ozone concentrations from 1960 to 2099 using multiple model simulations from …

To estimate the impact of emissions by road, aircraft and ship traffic on ozone and OH in the
present-day atmosphere six different atmospheric chemistry models have been used. Based …

Changes in the stratosphere‐troposphere exchange (STE) of ozone over the last few
decades have altered the tropospheric ozone abundance and are likely to continue doing so …