グリーンランドの出口氷河からの氷の排出の急速な変化
Ian M Howat1, Ian Joughin, Ted A Scambos
1Polar Science Center, Applied Physics Lab, University of Washington, 1013 Northeast 40th Street, Seattle, WA 98105-6698, USA. ihowat@apl.washington.edu
まとめ
グリーンランド グリーンランド
科学分野:
- 氷河学 氷河学とは
- 気候科学 気候科学
- 地球観測 地球観測
背景:
- グリーンランドの出口氷河は,世界の海面上昇に大きく貢献しています.
- 氷の放出の短期的な変動を理解することは,正確な気候モデルにとって極めて重要です.
研究 の 目的:
- グリーンランドの2つの主要な出口氷河の最近の氷の排出と質量損失の動態を分析するために.
- 氷河の質量バランスの短期的な変動の原因を調査する.
主な方法:
- 衛星から得られた地表の高度と速度データを利用した.
- 氷の流出と氷河の幾何学における時間的な変化を分析した.
主要な成果:
- 1年未満の期間 (2004年) で,結合された質量損失率の倍増が観察されました.
- 質量損失率は2006年までに以前の水準に戻ったが,これは前方再均衡によるものである.
- 総質量損失は重力による推定値のほんの一部であり,他の損失メカニズムを示唆している.
結論:
- 短期間で,氷河の幾何学の急速な再均衡が,大量損失に大きく影響する.
- アウトレット氷河のダイナミクスの高解像度モニタリングは,海面上昇の予測を洗練するために不可欠です.
- 重力による推定値との不一致は,統合された観測アプローチの必要性を強調しています.
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