グリーンランドの氷床の速度構造の変化
Eric Rignot1, Pannir Kanagaratnam
1Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 300-319, Pasadena, CA 91109-8099, USA. eric.rignot@jpl.nasa.gov
Science (New York, N.Y.)
|February 18, 2006
まとめ
グリーンランドの氷河は加速し,氷の排出量が増加しており,世界の海面上昇に大きく貢献しています. この傾向は北へ拡大しており,グリーンランドからの海面への貢献の将来の増加を示しています.
科学分野:
- 地球科学 地球科学 地球科学
- 氷河学 氷河学とは
- 気候科学 気候科学
背景:
- グリーンランドの氷床の動態は,世界の海面の変化を理解するために不可欠です.
- 以前の研究では,地域の氷の減少が示されましたが,広範な加速パターンについては,さらなる調査が必要でした.
研究 の 目的:
- グリーンランドの氷河加速の範囲とタイミングを定量化するために.
- グリーンランドの氷床の質量バランスに加速された氷の放出の影響を評価する.
主な方法:
- 衛星レーダーによるインターフェロメトリー観測を数年にわたって利用した.
- 氷河の速度の変化を分析し,加速現象を検出しました.
主要な成果:
- 1996年から2000年にかけて観測された広範囲の氷河加速は,北緯66度以下で,2005年までに北緯70度まで拡大した.
- 特にグリーンランド西部と東部の氷の急激な排出は,過去10年間で氷床の質量赤字を90から220km3/年に2倍にしました.
- 氷の消失の速度は増加しています.
結論:
- 氷河の北への加速が継続していることは,グリーンランドからの海面上昇への継続的かつ増大する貢献を示唆しています.
- グリーンランドの氷床の質量赤字は,広範囲にわたるダイナミックな氷の損失のために悪化しています.
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