極地氷床の質量バランス

Eric Rignot¹, Robert H Thomas

¹Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 300-235, Pasadena, CA 91109, USA. eric@adelie.jpl.nasa.gov

Science (New York, N.Y.)

|August 31, 2002

まとめ

グリーンランドと西南極の氷床は質量を失っているが,東南極の氷床は質量を失っている.

科学分野:

氷河学と極地科学について
気候変動に関する研究
地球システム科学地球システム科学

背景:

北極の氷床の質量バランスを理解することは,海面上昇を予測する上で極めて重要です.
以前の評価は,氷床の行動における複雑な地域的変動を示していた.

研究の目的:

主要な極の氷床の現在の質量バランスを決定する.
氷の質量の大幅な減少または増加地域を特定するために.
急速で説明がつかない変化の領域を強調する.

主な方法:

氷床質量バランスに関する最近のデータの分析.
氷床の薄くなり,厚くなりつつある状況を監視する.
重要な分野における氷の動態に関する観測研究.

主要な成果:

グリーンランドの氷床は,海岸付近で薄まり,質量が減少しています.
西南極の氷床は,地域によって異なるが,全体的に薄くなっている.
東南極の氷床の質量バランスは依然として不確実である.
急速な変化は,グリーンランドの東南,アムンセン海湾,南極半島で観察されています.

結論:

北極の氷床は,環境の変化に積極的に反応しています.
グリーンランドと西南極からの大量減量は,海面上昇に寄与している.
未確認のプロセスは,脆弱な南極とグリーンランドの地域で急速な変化を引き起こしています.

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