The decadal global atmospheric greenhouse gas concentration trends observed by Japan’s Greenhouse gases Observing SATellite (GOSAT)

（Japanese title: GOSAT・10年スケールでの世界の温室効果ガス濃度の観測）

This submission provides our input to the first Global Stocktake under the Paris Agreement. Our input focuses on the trends of the concentration of GHGs in the atmosphere observed by the Greenhouse gas Observing SATellite (GOSAT). 

Summary of the submission:

• A decadal global JAXA/GOSAT GHG product shows continued increases in global CO₂ and CH₄, which increased by 29 ppm and 97 ppb from June 2009 to June 2021, respectively. The product also presents the seasonal cycles of concentrations that are primarily attributable to natural GHG removals and the resulting carbon budget. 
• The Greenhouse gas Observing SATellite (GOSAT) is the world’s first GHG-dedicated space-based observatory launched in 2009 by Japan. GOSAT simultaneously monitors global changes in CO₂ and CH₄ atmospheric concentrations.
• GOSAT observations have collected CO₂ and CH₄ data over areas where ground-based observations are unavailable or sparse. GOSAT can monitor CO₂ and CH₄ at 100 times the number of locations than ground-based observation, filling in the observational gaps and collecting data on areas where climate mitigation impacts are expected, such as megacities.
• The JAXA/GOSAT GHG product is publicly available to assess CO₂ and CH₄ concentration changes. The product directly contributes to elucidating the global and local carbon cycle and monitoring the nation’s climate mitigation efforts toward the Paris Climate goal.