1National Center for Atmospheric Research, Boulder, Colorado, USA
2Research Center Jülich, Jülich, Germany
3Laboratoire d'Aérologie, UMR 5560, Université Paul Sabatier, Toulouse, France
4NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
5NOAA Climate Monitoring and Diagnostics Laboratory, Boulder, Colorado, USA
6Experimental Studies (ARQX), Air Quality Research Division, Environment Canada, 4905 Dufferin Street, Downsview, Ontario, Canada
*now at: Laboratoire des Sciences du Climat et de l'Environnement, CEA-CNRS-UVSQ, Gif-Sur-Yvette, France
Abstract. An ozone climatology based on ozone soundings for the last 15 years has been constructed for model evaluation and comparisons to other observations. Vertical ozone profiles for 41 stations around the globe have been compiled and averaged for the years 1980–1994 and 1995–2009. The climatology provides information about the median and the width of the ozone probability distribution function, as well as interannual variability of ozone between 1995 and 2009, in pressure and tropopause-referenced altitudes. In addition to single stations, regional aggregates are presented, combining stations with similar ozone characteristics. The Hellinger distance is introduced as a new diagnostic to compare the variability of ozone distributions within each region and used for model evaluation purposes. This measure compares not only the mean, but also the shape of distributions. The representativeness of regional aggregates is discussed using independent observations from surface stations and MOZAIC aircraft data. Ozone from all of these data sets show an excellent agreement within the range of the interannual variability, especially if a sufficient number of measurements are available, as is the case for West Europe. Within the climatology, a significant longitudinal variability of ozone in the troposphere and lower stratosphere in the northern mid- and high latitudes is found. The climatology is used to evaluate results from two model intercomparison activities, HTAP for the troposphere and CCMVal2 for the tropopause region and the stratosphere. HTAP ozone is in good agreement with observations in the troposphere within their range of uncertainty, but ozone peaks too early in the Northern Hemisphere spring. The strong gradients of ozone around the tropopause are less well captured by many models. Lower stratospheric ozone is overestimated for all regions by the multi-model mean of CCMVal2 models. Individual models also show major shortcomings in reproducing the shape of ozone probability distribution functions in various regions and different altitudes, which might have significant implications for the radiative budgets in those models.