GOSAT

GOSAT

The initiative is a Japanese satellite mission focused on greenhouse gas monitoring, developed to measure atmospheric concentrations of carbon dioxide and methane globally. It was designed through collaboration among Ministry of the Environment (Japan), National Institute for Environmental Studies, and Japan Aerospace Exploration Agency, with scientific ties to institutions such as NASA, European Space Agency, Japan Meteorological Agency, and research centers including National Oceanic and Atmospheric Administration, University of Tokyo, Caltech, and Massachusetts Institute of Technology. The program connects to international frameworks like the United Nations Framework Convention on Climate Change, Intergovernmental Panel on Climate Change, and networks such as Total Carbon Column Observing Network.

Overview

The satellite project was conceived within programs at Ministry of the Environment (Japan) and Japan Aerospace Exploration Agency to provide systematic measurements supporting climate assessments by organizations like Intergovernmental Panel on Climate Change and policy processes under United Nations Framework Convention on Climate Change. Engineering contributions came from industrial partners including Mitsubishi Electric Corporation, NEC Corporation, and IHI Corporation, while scientific instrument teams involved researchers from National Institute for Environmental Studies, University of Tokyo, Kyoto University, Osaka University, and Tohoku University. The mission complements other observatories such as Orbiting Carbon Observatory, SCIAMACHY, TES (instrument), and GOME.

Mission Objectives

Primary objectives targeted global mapping of column-averaged dry-air mole fractions to inform assessments by Intergovernmental Panel on Climate Change and emissions reporting under United Nations Framework Convention on Climate Change. The mission supported process studies linked to terrestrial biosphere research at institutions like Carnegie Institution for Science and Woods Hole Research Center and ocean biogeochemistry studies by groups such as Scripps Institution of Oceanography and Lamont–Doherty Earth Observatory. Objectives included providing validation datasets for models run at European Centre for Medium-Range Weather Forecasts, NASA Goddard Institute for Space Studies, and Max Planck Institute for Meteorology.

Spacecraft and Instruments

The spacecraft bus integrated subsystems produced by Mitsubishi Electric Corporation and avionics from NEC Corporation, with payload engineering led by teams from National Institute for Environmental Studies and Osaka University. The primary instrument was a Fourier-transform spectrometer analogous in concept to instruments developed at NASA Goddard Space Flight Center and Jet Propulsion Laboratory, complemented by a cloud and aerosol imager with heritage to sensors from MODIS and engineering links to projects at European Space Agency facilities. Calibration and validation efforts engaged metrology groups at National Metrology Institute of Japan and planetary science laboratories such as Institute of Space and Astronautical Science. Ground segment operations involved facilities at Tsukuba Space Center, data centers at National Institute for Environmental Studies, and outreach collaborations with World Meteorological Organization.

Launch and Orbit

The payload was launched on a H-IIA vehicle from Tanegashima Space Center into a sun-synchronous orbit used by missions like Landsat, Terra (satellite), and Sentinel-3. The orbital parameters provided global coverage similar to observational strategies employed by Envisat and NOAA polar platforms, enabling repeat coverage patterns employed in missions such as SMAP and GRACE. Launch campaigns coordinated with agencies including Japan Aerospace Exploration Agency and commercial partners analogous to those working with Arianespace.

Data Products and Processing

Data products included column-averaged CO2 and CH4 retrievals comparable to datasets from Orbiting Carbon Observatory-2 and reanalysis systems at European Centre for Medium-Range Weather Forecasts. Processing chains adapted algorithms from spectroscopy groups at University of Leicester, University of Bremen, and California Institute of Technology, and used radiative transfer models developed at Laboratoire de Météorologie Dynamique and Aerospace Corporation. Validation used surface flask networks coordinated by World Meteorological Organization and in situ programs run by NOAA and Scripps Institution of Oceanography. Data dissemination leveraged archives similar to NASA Earthdata and Copernicus Open Access Hub practices and supported assimilation into Earth system models at Met Office and NASA Goddard.

Scientific Results and Applications

Scientific outputs demonstrated regional enhancements of carbon dioxide and methane linked to anthropogenic sources and natural fluxes, informing inventories used by United Nations Framework Convention on Climate Change processes and studies at International Energy Agency. Papers produced with collaborators from University of California, Berkeley, ETH Zurich, Potsdam Institute for Climate Impact Research, and Max Planck Institute for Biogeochemistry improved understanding of sink dynamics in regions studied by the Amazon Cooperation Treaty Organization and boreal ecosystems monitored by Russian Academy of Sciences. Applications included urban emissions monitoring in cities such as Tokyo and Los Angeles, validation of terrestrial biosphere models used at Carnegie Institution for Science, and constraints on wetland methane emissions relevant to research at National Wetlands Research Center.

International Collaboration and Operations

Operational and scientific collaborations extended across agencies including NASA, European Space Agency, NOAA, World Meteorological Organization, Intergovernmental Panel on Climate Change, and research institutions like University of Tokyo, Massachusetts Institute of Technology, Imperial College London, and Potsdam Institute for Climate Impact Research. Calibration and validation campaigns partnered with national measurement programs from United States Geological Survey, Chinese Academy of Sciences, Indian Space Research Organisation, Korean Aerospace Research Institute, and regional observing networks such as Total Carbon Column Observing Network and ICOS ERIC. The mission fostered data sharing aligned with principles advocated by Group on Earth Observations and supported decision-making under international frameworks like the Paris Agreement.

Category:Earth observation satellites