Recent simulations predicted that the stratospheric ozone layer will likely return to pre-1980 levels in the middle of the 21st century, as a result of the decline of ozone depleting substances under the Montreal Protocol. Since the ozone layer is an important component in determining stratospheric and tropospheric-surface energy balance, the recovery of stratospheric ozone may have significant...

Highest atmospheric ozone production rates can be found at around 30 km in the tropical stratosphere, leading to ozone mixing ratios of about 10 ppmv. Those stratospheric air masses are then transported to extra-tropical latitudes via the Brewer-Dobson circulation. This is considered the main mechanism to generate midand high latitude ozone. By applying the climate-chemistry models E39/C and MA...

The ozone radiative forcings (RFs) resulting from projected changes in climate, ozone-depleting substances (ODSs), non-methane ozone precursor emissions and methane between the years 2000 and 2100 are calculated using simulations from the UM-UKCA chemistry– climate model (UK Met Office’s Unified Model containing the United Kingdom Chemistry and Aerosols sub-model). Projected measures to improve...

This study investigates ozone changes and the individual impacts of transport and chemistry on those changes. We specifically examine (1) variation related to El Niño Southern Oscillation, which is a dominant mode of interannual variation of tropospheric ozone, and (2) long-term change between the 2000s and 2100s. During El Niño, the simulated ozone shows an increase (1 ppbv/K) over Indonesia, ...

The reliance on global mean radiative forcing as an index of climate change is questionable for highly inhomogeneous forcing agents such as tropospheric ozone or aerosols. Using a general circulation model, we have carried out a pair of equilibrium climate simulations with previously calculated present-day and preindustrial ozone distributions. We show that the radiative forcing of 0.49 W m-2 d...

The increase in civil world fleet ship emissions during the period 2000-2007 and the effects on key tropospheric oxidants are quantified using a global Chemical Transport Model (CTM). We estimate a substantial increase of 33% in global ship emissions over this period. The impact of ship emissions on tropospheric oxidants is mainly caused by the relatively large fraction of NOx in ship exhaust. ...

A global three-dimensional (i.e. latitude, longitude, altitude) climatology of tropospheric ozone is derived from the ozone sounding record by trajectory mapping. Approximately 52 000 ozonesonde profiles from more than 100 stations worldwide since 1965 are used. The small number of stations results in a sparse geographical distribution. Here, forward and backward trajectory calculations are per...

[1] 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 in the coming century as climate changes. Combining an updated linearized stratospheric ozone chemistry (Linoz v2) with parameterized polar stratospheric clouds (PSCs) chemistry, a 5-year (2001–2005) sequence of the Europ...

The chemical and dynamical processes governing the zonal variability of tropical tropospheric ozone and carbon monoxide are investigated for November 2004 using satellite observations, in-situ measurements, and chemical transport models in conjunction with inverse estimated surface emissions. Vertical ozone profile estimates from the Tropospheric Emission Spectrometer (TES) and ozone sonde meas...

We analyze tropospheric column ozone (TCO) data observed by satellite instruments over East Asia for 15 years (from 1995 to 2009), and investigate the relationship between enhanced TCO (E-TCO) and ozone intrusion from the stratosphere near the subtropical jet (STJ). A belt of E-TCO is observed at mid-latitude over East Asia throughout the year; the belt is located at latitudes approximately equ...