Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 4 9/10 2004 10.5194/acp-4-2345-2004 http://www.atmos-chem-phys.net/4/2345/2004/ http://www.atmos-chem-phys.net/4/2345/2004/acp-4-2345-2004.html http://www.atmos-chem-phys.net/4/2345/2004/acp-4-2345-2004.pdf 2345 2352 2004-11-30 Non-coincident inter-instrument comparisons of ozone measurements using quasi-conservative coordinates L. R. Lait P. A. Newman M. R. Schoeberl T. McGee L. Twigg E. V. Browell M. A. Fenn W. B. Grant C. F. Butler R. Bevilacqua J. Davies H. DeBacker S. B. Andersen E. Kyrö E. Kivi P. von der Gathen H. Claude A. Benesova P. Skrivankova V. Dorokhov I. Zaitcev G. Braathen M. Gil Z. Litynska D. Moore M. Gerding Science Systems and Applications, Inc., Lanham, Maryland, USA NASA Goddard Space Flight Center, Greenbelt, Maryland, USA NASA Langley Research Center, Langley, Virginia, USA SUNARC, San Francisco, California, USA U. S. Naval Research Laboratory Meteorological Service of Canada, Ontario, Canada Danish Meteorological Institute, Copenhagen, Denmark Finnish Meteorological Institute, Sodankylä, Finland Alfred Wegener Institute, Potsdam, Germany Deutscher Wetterdienst Meteorologisches Observatorium, Hohenpeissenberg, Germany Czech Hydrometeorological Institute, Prague, Czech Republic Central Aerological Observatory, Dolgoprudny, Russia Norsk Institutt for Luftforskning, Kjeller, Norway Instituto Nacional de Técnica Aeroespacial, Madrid, Spain Institute of Meteorology and Water Management, Legionowo, Poland U. K. Meteorological Office, Wokingham, Berks, United Kingdom Leibniz-Institute of Atmospheric Physics, Kühlungsborn, Germany Ozone measurements from ozonesondes, AROTAL, DIAL, and POAM III instruments during the SOLVE-2/VINTERSOL period are composited in a time-varying, flow-following quasi-conservative (PV-θ) coordinate space; the resulting composites from each instrument are mapped onto the other instruments' locations and times. The mapped data are then used to intercompare data from the different instruments. Overall, the four ozone data sets are found to be in good agreement. AROTAL shows somewhat lower values below 16 km, and DIAL has a positive bias at the upper limits of its altitude range. These intercomparisons are consistent with those obtained from more conventional near-coincident profiles, where available. Although the PV-θ mapping technique entails larger uncertainties of individual profile differences compared to direct near-coincident comparisons, the ability to include much larger numbers of comparisons can make this technique advantageous.