北極気候の温暖化と最後の氷期間の氷床の退却をシミュレートする
Bette L Otto-Bliesner1, Shawn J Marshall, Jonathan T Overpeck
1Climate and Global Dynamics Division, National Center for Atmospheric Research (NCAR), Boulder, CO 80305, USA. ottobli@ucar.edu
Science (New York, N.Y.)
|March 25, 2006
まとめ
北極の温暖化と氷河の融解は,将来のリスクをもたらします. この研究では,気候と氷床のモデルを用いて,グリーンランドと北極の氷床が,最後の氷期間に2.2〜3.4メートルの海面上昇を引き起こしたことを示しました.
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 氷河学 氷河学とは
- 気候モデリング
背景:
- 北極の温暖化と極地氷河の融解は著しく増加すると予測されていますが,その正確な規模は不明です.
- 過去の氷河期間の理解は,将来の気候と海面の変化を予測するために不可欠です.
研究 の 目的:
- 北半球の高緯度の温暖化と,最後の氷期間の北極の氷床への影響を評価する.
- グリーンランドの氷床やその他の北極の氷床が,この期間に海面上昇に与える影響を定量化する.
主な方法:
- 過去の気候条件をシミュレートするために,グローバルな気候モデルを使用しました.
- アイスフィールドの振る舞いを評価するために,ダイナミックな氷床モデルを使用しました.
- モデル検証のための統合された古気候データと氷芯の制約.
主要な成果:
- シミュレートされた気候は,過去の温暖化に関する古気候観測と正確に一致しました.
- グリーンランドの氷床と周辺の北極の氷床は,海面上昇に大きく貢献していることが判明しました.
- これらの氷床による海面上昇への寄与は2.2メートルから3.4メートルと推定されている.
結論:
- 最後の間氷期は,将来の北極の気候変化に貴重な類似点を提供します.
- 北極の氷床,特にグリーンランドの氷床は,世界の海面に影響を与える大きな力を持っています.
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