Quantification of strong emissions of methane in the Arctic using spectral measurements from TANSO-FTS and IASI

• Main Authors: Bourakkadi, Zakia, Payan, Sébastien, Bureau, Jérôme
• Other Authors: 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 2015
• Subjects: [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; Arctic; permafrost
• Online Access: https://hal.science/hal-01142226; https://hal.science/hal-01142226/document; https://hal.science/hal-01142226/file/EGU2015-finall.pdf

International audience Methane is the second most important greenhouse gas after the carbon dioxide but it is 25 times more effective incontributing to the radiative forcing than the carbon dioxide.Since the pre-industrial times global methane concentration have more than doubled in the atmosphere. Thisincrease is generally caused by anthropogenic activities like the massif use and extraction of fossil fuel, rice paddyagriculture, emissions from landfills.In recent years, several studies show that climate warming and thawing of permafrost act on the mobiliza-tion of old stored carbon in Arctic causing a sustained release of methane to the atmosphere(2),(3),(4).The methane emissions from thawing permafrost and methane hydrates in the northern circumpolar region willbecome potentially important in the end of the 21st centry because they could increase dramatically due to therapid climate warming of the Artic and the large carbon pools stored there.The objective of this study is to evaluate and quantify methane strong emissions in this region of the globeusing spectral measurements from the Thermal And Near Infrared Sensor for carbon Observations-FourierTransform Spectrometer (TANSO-FTS) and the Infrared Atmospheric Sounding Interferometer (IASI). We usealso the LMDZ-PYVAR model to simulate methane fluxes and to estimate how they could be observed by InfraredSounders from space.To select spectra with high values of methane we developed a statistical approach based on the singularvalue decomposition. Using this approach we can identify spectra over the important emission sources of methaneand we can by this way reduce the number of spectra to retrieve by an line-by-line radiative transfer model inorder to focus on those which contain high amount of methane.In order to estimate the capacity of TANSO-FTS and IASI to detect peaks of methane emission with shortduration at quasi-real time, we used data from MACC (Monitoring Atmospheric Composition and Climate)simulations to compute spectra which we are compared to ...