日本地球惑星科学連合2025年大会

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セッション記号 M (領域外・複数領域) » M-IS ジョイント

[M-IS15] グローバル南極学

2025年5月27日(火) 10:45 〜 12:15 101 (幕張メッセ国際会議場)

コンビーナ:石輪 健樹(国立極地研究所)、草原 和弥(海洋研究開発機構)、箕輪 昌紘(北海道大学・低温科学研究所)、飯塚 睦(産業技術総合研究所)、座長:箕輪 昌紘(北海道大学・低温科学研究所)


12:00 〜 12:15

[MIS15-12] An 11-Year Common Periodic Mass Changes in Dronning Maud Land and Amundsen Sea Embayment Driven by Solar Cycle

*施 天焔1奥野 淳一2入江 芳矢1 (1.京都大学大学院理学研究科附属地球熱学研究施設、2.国立極地研究所 )

キーワード:南極氷床、衛星重力

Since the early 1990s, satellite observations have consistently shown Antarctica experiencing long-term mass loss. However, our understanding of the climate drivers behind these changes remains insufficient. This study explores the relationship between Antarctica Ice Sheet (AIS) mass changes and large-scale climate indices through statistical analysis.
Using Independent Component Analysis (ICA), we separated AIS mass changes observed by GRACE/GRACE-FO into statistically independent modes, which were then compared with climate indices to investigate primary driving factors. Our analysis reveals a previously undocumented coupling mechanism between the rapidly losing Amundsen Sea Embayment (AMS) in West Antarctica and the mass-gaining Dronning Maud Land (DML) in East Antarctica.
Detrended satellite altimetry data from both regions exhibit a coherent ~11-year oscillation pattern (r > 0.7, p < 0.01) strongly synchronized with solar flux variations. Comparative analysis with Surface Mass Balance (SMB) model suggests that most of these decadal fluctuations can be attributed to meteorological processes modulated by solar forcing.
In addition to southern mid-latitude climate modes such as El Niño-Southern Oscillation (ENSO) and Southern Annular Mode (SAM), Solar cycle-driven tropical sea surface temperature (SST) anomalies changes appear to regulate meridional mass transport through atmospheric teleconnections. To verify this hypothesis, we further examined SST anomalies and their relationship with the observed mass changes. Our study reveals the direct driving force of solar activity on AIS changes, providing a new perspective on why DML and AMS are the most significant regions of mass change across Antarctica.