まとめ
西南極の氷床は,1万5千年の海面上昇により300メートルも薄くなっている. この氷床の撤退は,世界の海面上昇に大きく貢献しています.
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 氷河学 氷河学とは
- 海水面に関する研究.
背景:
- 西南極の氷床 (WAIS) は,過去1万5千年にわたって大きな変化を経験してきました.
- 過去の氷床の動態を理解することは,将来の海面上昇を予測する上で極めて重要です.
研究 の 目的:
- WAISの薄くなる主な要因を調査する.
- グローバル海面の変化に対するWAISの退却の寄与を定量化するために.
主な方法:
- 過去の氷床の広がりを再構築するために地質学的記録の分析.
- 氷床の動態と相関する海水位データ解釈.
主要な成果:
- WAISのマージンは,過去1万5千年にわたって大幅に縮小した.
- 約300メートルの氷床の薄れが起こった.
- WAISは,ウィスコンシン州時代後半に30%幅が広い.
- WAISの縁のホロセンの後退は,世界の海面が約6メートル上昇した.
結論:
- 海面上昇はWAISの薄くなる主な原因である.
- 過去のWAISの撤退は,世界の海面に重大な影響を及ぼしました.
- この研究は,西南極の氷床が気候や海面の変動に敏感であることを強調しています.
関連する概念動画
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