[A-CG36] 衛星による地球環境観測

[ACG36-P19] GOSAT calibration activities and observation plans for advanced GHG measurements

*塩見 慶¹、久世 暁彦¹、須藤 洋志¹、菊地 信弘¹、片岡 文恵² (1.宇宙航空研究開発機構、2.リモート・センシング技術センター)

JAXA’s GOSAT has been operating since 2009 and GOSAT-2 since 2018 to monitor the greenhouse gases (GHGs) carbon dioxide (CO₂) and methane (CH₄) by a Fourier Transform Spectrometer. The total column-average dry air mole fractions of CO₂ (XCO₂), and CH₄ (XCH₄) are measured from space using surface-reflected sunlight at near-IR wavelengths. Additionally, the partial column fractions of CO₂ and CH₄ in troposphere are retrieved together with thermal-IR wavelengths radiated from atmosphere. The partial column fraction in tropospheric lower altitude has an advantage to take local emissions before mixing rather than the total column-average fraction. The observation pattern over urban city area would be further optimized for taking local emissions efficiently. The GOSAT and the other GHG missions, NASA OCO and ESA TROPOMI are collaborated in calibration activities to improve GHG observation accuracy. We will present updated GOSAT calibration activities and observation plans for detecting local emissions by using tropospheric partial column fraction.