Cloud filter for CO retrieval from IMG infrared spectra using ECMWF temperatures and POLDER cloud data

Juliette Hadji-Lazaro (1) , Cathy Clerbaux (1) , Pierre Couvert (2, 3) , Patrick Chazette (2, 3) , Cathy Boonne (4)

1 SA - Service d'aéronomie
2 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
3 CAE - Chimie Atmosphérique Expérimentale
4 IPSL - Institut Pierre-Simon-Laplace

Infrared atmospheric measurements provided by space nadir looking remote sensors are affected by the presence of clouds. To obtain cloud-free CO global distributions from the radiance spectra measured by the IMG instrument, we have developed a simple method of spectra selection using skin temperatures provided by the ECMWF model. Information on the cloud cover was provided by the cloud data of the POLDER instrument which flew aboard the same platform as IMG. We show that a filter based on skin temperature, with thresholds of 8 K over sea and 15.3 K over land, allows to remove most of the cloudy cases.

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

Juliette Hadji-Lazaro, Cathy Clerbaux, Pierre Couvert, Patrick Chazette, Cathy Boonne. Cloud filter for CO retrieval from IMG infrared spectra using ECMWF temperatures and POLDER cloud data. Geophysical Research Letters, 2001, 28 (12), pp.2397-2400. ⟨10.1029/2000GL012342⟩. ⟨insu-01266815⟩