The European regional ozone distribution and its links with the global scale for the years 1992 and 2015

Because of global-scale increases in trace gas emissions, ozone concentrations in northern hemisphere may increase over the next decade, driving up ozone concentrations within Europe. Over this same period, policy actions are anticipated which will reduce the internal European regional-scale ozone production capacity. The overall success of these regional policies will be determined by the resultant of these global- and regional-scale influences. A global three-dimensional Lagrangian chemistry model STOCHEM has been used to look at the relative magnitudes of these two influences on the European regional ozone distribution under some illustrative emission scenarios up to the year 2015. Substantial reductions in European NOx emissions should bring a significant improvement in ozone air quality, but they may not be enough to keep future peak ozone levels below internationally accepted environmental criteria without action on the global scale to control emissions of tropospheric ozone precursors: methane, carbon monoxide, NOx and VOCs.