Greenhouse gas observation by TANSO-3 onboard GOSAT-GW

Abstract

Global Observing SATellite for Greenhouse gases and Water cycle (GOSAT-GW) is a Japanese Earth observation satellite to be launched in FY2023 and jointly funded by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) and the Ministry of the Environment (MOE). One of GOSAT-GW's mission instrument is Total Anthropogenic and Natural Emissions Mapping Spectrometer-3 (TANSO-3). TANSO-3 is a 3-band grating imaging spectrometer with two different selectable spatial observation modes, Wide Mode and Focus Mode. MOE and National Institute for Environmental Studies (NIES) are responsible for global observation of greenhouse gases (GHGs) and air pollutants, carbon dioxide (CO₂), methane (CH₄), and nitrogen dioxide (NO₂), by TANSO-3. TANSO-3 instrument is being developed by Japan Aerospace Exploration Agency (JAXA) with the funding from MOE. The missions of TANSO-3 include (1) monitoring of whole-atmosphere mean concentrations of CO₂ and CH₄, (2) validation of nationwide anthropogenic emissions of GHGs, and (3) detection of GHGs emissions from large sources, such as megacities and power plants. The validation of nationwide anthropogenic emissions of GHGs is one of emerging challenges related to the Paris Agreement and contributions of TANSO-3's global data strongly expected. NO2 data from TANSO-3 will be also utilized in the identification and characterization of point sources which use fossil fuels and their plumes.