Intercomparison of remote measurements of stratospheric NO and NO2

During the 1982 and 1983 Balloon Intercomparison Campaigns, the vertical profile of stratospheric NO₂ was measured remotely by nine instruments and that of NO by two. Total overhead columns were measured by two more instruments. Between 30 and 35km, where measurements overlapped, agreement between NO profiles was within ±30%, which is better than the accuracies claimed by the experimenters. Between 35 and 40km there was similarly good agreement between NO₂ profiles, but below 30km, differences of greater than a factor three were found. In the second Campaign, NO₂ values from most instruments agreed within their quoted errors, except that the Oxford radiometer gave much lower values; but the first Campaign and the column measurements show a more uniform spread of results.These differences below 30km could not be resolved, but new laboratory measurements are planned which should do so.     

The Balloon Intercomparison Campaigns an introduction and overview

The Balloon Intercomparison Campaigns of 1982 and 1983 compared balloon-borne sensors of HCl, HNO3, NO2, NO and O3, and measured many other stratospheric constituents. Most sensors were remote rather than in-situ. In the 1982 campaign, three large gondolas were successfully launched from Palestine, Texas on the same day; in the 1983 campaign, four gondolas were launched within 3 days. Accompanying papers describe the results of these successful intercomparisons.