グリーンランドのヤコブシャヴン・イスブレイ氷河の速度の大幅な変動
Ian Joughin1, Waleed Abdalati, Mark Fahnestock
1Jet Propulsion Lab, California Institute of Technology, USA. ian@apl.washington.edu
Nature
|December 4, 2004
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
- リモートセンシング (リモートセンサー)
背景:
- グリーンランドの氷床の質量バランスは,出口氷河の流れ率に影響されます.
- グリーンランドの最大の出口氷河であるJakobshavn Isbraeは,1991年以来,繰り返し調査されています.
- 氷河の速度の変化を理解することは,氷床の質量バランスの評価に不可欠です.
研究 の 目的:
- 遥感データを用いて,1992年から2003年の間,ヤコブシュヴァン・イスブレの速度を測定する.
- 氷河の流れ速度における時間的変動を分析するために.
- 氷河の速度の変化が氷の流出に与える影響を評価する.
主な方法:
- 速度測定のためのリモートセンシングデータを活用した.
- 1992年から2003年の氷河の速度データを分析した.
- 氷河の厚みや薄くなる速度の変化と相関する.
主要な成果:
- Jakobshavn Isbraeの速度における有意な時間的変動が検出されました.
- 1985年から1992年まで速度が低下し,2003年まで大幅な増加が続いた.
- 速度の変化は,観測された氷河の厚みや薄くなるパターンと一致しています.
結論:
- 急速に流れる氷河は10年未満のスケールで氷の排出を大幅に変化させることができます.
- 氷河の速度動態は,気候変動への迅速な対応の可能性を示しています.
- Jakobshavn Isbraeの速度の最近の変化は,気候の変化に対する敏感性を強調しています.
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