急速な底の融解は,南極の近くに広く広がっています アイスシートの接地ライン
Eric Rignot1, Stanley S Jacobs
1Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 300-235, Pasadena, CA 91109-8099, USA. eric@adelie.jpl.nasa.gov
まとめ
南極の氷河は,下から溶け,これまで考えられていたよりも高いペースで溶けています. 海洋温度の上昇は,この基礎層の融解を著しく加速させ,氷棚や氷河を深水へのアクセスで脅かす.
科学分野:
- 氷河学 氷河学とは
- 海洋学 海洋学とは
- 気候科学 気候科学
背景:
- 南極の氷の減少は,世界の海面上昇に寄与しています.
- 接地線における氷と海洋の相互作用を理解することは,将来の氷の放出を予測するために極めて重要です.
研究 の 目的:
- 南極の出口氷河の基礎融解速度を定量化するために.
- 海洋温度と氷河の融解の関係について調査する.
主な方法:
- 融解速度を測定するために,衛星レーダー干渉計が使用されました.
- 分析は,接地線付近の大きな出口氷河に焦点を当てた.
主要な成果:
- 観測された底層の融解率は,以前に想定されたより著しく高い.
- 融解率は,海洋温度の0.1°C上昇ごとに1年に1メートル増加する.
- 接地線への直接的な深水アクセスを持つ氷河は,より高い脆弱性を示しています.
結論:
- 基礎層の融解は,南極の氷の安定性に影響を及ぼす重要なプロセスです.
- 海洋温度の上昇は,南極の氷河と氷棚に重大な脅威をもたらしています.
- 融解速度の正確なデータは,気候モデルと海面上昇予測に不可欠です.
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