衛星による重力測定は,グリーンランドの氷床が急速に溶けていることを確認しています

J L Chen¹, C R Wilson, B D Tapley

¹Center for Space Research, University of Texas at Austin, Austin, TX 78712, USA. chen@csr.utexas.edu

Science (New York, N.Y.)

|August 12, 2006

まとめ

グリーンランドグリーンランド

科学分野:

地球科学地球科学地球科学
気候科学気候科学
氷河学氷河学とは

背景:

グリーンランドの氷の質量の変化は,世界の海面上昇を理解する上で極めて重要です.
衛星観測は,大規模な冷凍圏の変化を監視するために不可欠です.

研究の目的:

2002年4月から2005年11月までのグリーンランドの氷の質量の変化を推定する.
GRACE (Gravity Recovery and Climate Experiment) のデータを他の遠隔感知方法と比較して検証するために.

主な方法:

GRACE衛星ミッションからの時間変数重力測定を用いて.
GRACEデータに固有の空間フィルタリングと限られた解像度の修正を適用する.

主要な成果:

グリーンランドの氷の融解の推定総速度: -239 +/- 23立方キロメートル/年.
主に東グリーンランドで顕著な氷の減少が観察されました.
GRACEのデータは,2004年夏以降,グリーンランド南東部の融解が加速していることを示している.

結論:

GRACEの衛星データは,グリーンランドの氷の質量損失の信頼性の高い見積もりを提供します.
この結果は,衛星レーダー干渉測定を用いた独立した評価と一致しています.
グリーンランドの加速した融解傾向は,継続的な監視の必要性を強調しています.

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