CONICET | Buscador de Institutos y Recursos Humanos

Abstract: from 1993 to 2000, the Institute for Environmental Studies (IEMA) depending of the University of Mendoza, carried out ground-based stratospheric ozone measurements by means of millimetre wave radiometry (project Tropwa). In this paper we present a complete theoretical study necessary to qualify the uncertainties in the retrieval process. This type of error analysis is often used to characterize any remote sensing experiment. To evaluate and validate the quality of the obtained Tropwa stratospheric ozone profiles, we also performed a comparative study using the ozone profiles measured by the Haloe experiment. This study includes a comparison of individual profiles and of seasonal averages from 1993 to 2000. Given the coarser height resolution of the retrieved ozone profiles from microwave ground based instrument, compared to those obtained from the solar occultation technique, the Haloe profiles were averaged by convolving them with the averaging kernels of the Tropwa retrieval process. This error analysis and the comparison tests allowed us to evaluate and characterize the retrieval of our instrument. It can be seen that between 20 to 40 km the Tropwa instrument is able to retrieve ozone profiles with absolute errors varying from 10 to 20 %, and relative errors less than 5%, with a height resolution (fwhm) that varies from 5 to 11 km depending on the altitude. The seasonal variations show consistent patterns but having Tropwa measurements a systematic lower peak value of about 0.5 to 0.7 ppmv. The mayor discrepancies between both set of profiles occurs in the period of may-june with values varying around +8 to ?10% (+0.4 to ?0.8 ppmv). This difference is partially due to the coarser height resolution of our instrument. Keywords: Error analysis, remote sensing, stratospheric ozone profiles, validation

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