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Louisnard, N.

Publications and source records attributed to Louisnard, N..

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 35 km, where measurements overlapped, agreement between NO profiles was within + or - 30 percent, which is better than the accuracies claimed by the experimenters. Between 35 and 40 km, there was similarly good agreement between NO2 profiles, but below 30 km, differences of greater than a factor of 3 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; the first campaign and the column measurements show a more uniform spread of results.

Roscoe, H. K.↗

Nitrogen species

Total odd nitrogen, NO(y), may be defined as the sum of all active nitrogen species that interchange photochemically with one another on a time scale of the order of weeks or less. As noted, NO + NO2 reactions dominate the processes controlling the ozone balance in the contemporary stratosphere. The observational data from non-satellite platforms are reviewed. The growth in available satellite data in the past four years is considered. Some of the most important scientific issues are discussed, taking into account new results from atmospheric models (mainly 2-D). The model results are compared with the observational data.

Harries, J. E.↗

Ozone intercomparisons from the Balloon Intercomparison Campaign

Intercomparisons of remote and in-situ techniques used to measure stratospheric ozone are made using results obtained on the Balloon Intercomparison Campaign of 1982 and 1983. Two in-situ and four remote instruments participated. These included ECC ozonesondes, a UV absorption photometer, and microwave emission, IR emission, and absorption spectrometers. Differences are generally less than 15 percent, and are within the quoted error bars. Flights which involved different sets of instruments were made on four separate days, and results are intercompared in plots of ozone density versus altitude. A careful assessment of errors was made for each instrument, and a plot of absolute errors versus altitude is given.

Robbins, D.↗