CO SEASONAL VARIABILITY AND TREND OVER PARIS MEGACITY USING GROUND-BASED QUALAIR FTS AND SATELLITE IASI-METOP MEASUREMEN

摘要

In a growing world with more than 7 billion inhabitants and big emerging countries such as China, Brazil andrnIndia, emissions of anthropogenic pollutants are increasing continuously. Monitoring and control of atmosphericrnpollutants in megacities have become a major challenge for scientists and public health authorities in environmentalrnresearch area. The QualAir platform at University Pierre et Marie Curie (UPMC), is an innovating experimentalrnresearch platform dedicated to survey urban atmospheric pollution and air quality. A Bruker Optics IFS 125HR Fourierrntransform spectrometer belonged to the Laboratoire de Physique Moléculaire pour l’Atmosphère et l’Astrophysiquern(LPMAA), was adapted for ground-based atmospheric measurements. As one of the major instruments of the QualAirrnplatform, this ground-based Fourier transform spectrometer (QualAir FTS) analyses the composition of the urbanrnatmosphere of Paris, which is the third largest European megacity. The continuous monitoring of atmospheric pollutantsrnis essential to improve the understanding of urban air pollution processes. Associated with a sun-tracker, the QualAirrnremote sensing FTS operates in solar infrared absorption and enables to monitor many trace gases, and to follow uprntheir variability in the Ile-de-France region. Concentrations of atmospheric pollutants are retrieved by the radiativerntransfer model PROFFIT. These ground-based remote sensing measurements are compared to ground in-siturnmeasurements and to satellite data from IASI-MetOp (Infrared Atmospheric Sounding Interferometer). The remoternsensing total column of the carbon monoxide (CO) obtained from January 2009 to June 2012, has a seasonal variabilityrnwith a maximum in April and a minimum in October. While, after 2008, the mean CO level is quite stable (nornsignificant decrease as before 2008).