Evolution of SST and XCO 2 in the summer ice free Arctic Ocean: is IASI able to contribute to climate change studies?

• Main Authors: Camy-Peyret, Claude, Bureau, Jérôme, Payan, Sébastien
• Other Authors: Institut Pierre-Simon-Laplace (IPSL), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2016
• Subjects: [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; Arctic; Arctic Ocean; Climate change; ice pack
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-01304902

International audience The Arctic Ocean is a very important region of the globe in which the effect of climate change can bedetected over short time periods. We have used the possibility provided by the two infrared soundersIASI-A and IASI-B on the MetOp platforms to retrieve the sea surface temperature (Tsurf) and thecolumn averaged mixing ratio of several trace gases including CO2. A strict filtering based on theAVHRR cloud fraction and the radiance analysis within the IASI footprints lead to a large number ofspectra for which a 1D-var inversion (Tsurf and XCO2 as the main parameters in the state vector, plusscaling factors for the profiles of H2O and O3) has been performed. For this purpose, we used duringretrieval the atmospheric window between 940 and 980 cm-1 (CO2 laser band) for which thesensitivity to the surface is maximum. The statistics of the comparison between IASI-A and IASI-Bretrievals will be presented and compared to the corresponding Eumetsat L2 products. The months ofJuly, August and September for the years 2013 to 2015 have been considered since in these Arcticsummer conditions the ice pack coverage is reduced. The monthly climatology for the consecutiveyears from 2010 (for which only IASI-A was in orbit) to 2015 is confirming that IASI can indeed be used for climate change studies.