Detection of collapsing peripheral bulge in Antarctica using satellite gravity data and GIA modeling

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K22372
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0204:Astronomy, earth and planetary science, and related fields
• Research Institution: National Institute of Polar Research
• Principal Investigator: Irie Yoshiya 国立極地研究所, 先端研究推進系, 特任研究員 (30881015)
• Project Period (FY): 2020-09-11 – 2023-03-31
• Keywords: GIA / 南極氷床 / 地球内部粘弾性構造

Outline of Final Research Achievements

Estimates of Antarctic ice mass change from the GRACE gravity signal require subtraction of the gravity rates predicted by the GIA model (GIA correction). However, Antarctica is known to have a complex viscoelastic Earth structure. To improve the accuracy of the GIA model in Antarctica, we study collapsing peripheral bulge in Antarctica using GIA modeling and GRACE data. In the course of the study, some important findings are made regarding the dependence of the Antarctic GIA correction for GRACE data on the viscoelastic Earth structure.

Free Research Field

固体地球物理学

Academic Significance and Societal Importance of the Research Achievements

近年の地球温暖化により加速する南極氷床融解は、全球的な海水準上昇を引き起こすため、人類社会への影響も大きく、南極氷床質量変動を推定することは非常に重要である。南極氷床質量変動を推定する上で、氷床変動に伴う固体地球の粘弾性応答(GIA) を評価する必要がある。本研究で得られた南極域におけるGIAの地球内部粘弾性構造依存性の理解は、南極氷床質量変動の正確な推定に貢献しうる点で、学術的・社会的意義を持つと考えられる。