将来の氷床の不安定性と,海面の急速な上昇のための古気候の証拠
Jonathan T Overpeck1, Bette L Otto-Bliesner, Gifford H Miller
1Institute for the Study of Planet Earth, Department of Geosciences, and Department of Atmospheric Sciences, University of Arizona, Tucson, AZ 85721, USA. jto@u.arizona.edu
Science (New York, N.Y.)
|March 25, 2006
まとめ
地球温暖化により,極地の氷床が溶け,海面が著しく上昇する可能性があります. 過去の融解は,将来の海面上昇が予想以上に加速する可能性があることを示唆している.
科学分野:
- 気候科学 気候科学
- 氷河学 氷河学とは
- 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,古代気候学 (paleoclimatology) とは
背景:
- 極地氷床の融解による海面上昇は,気候変動による主要な脅威である.
- 極地地域は,海面の上昇に伴う氷河期間の時期と同様の温暖化を経験する可能性があります.
研究 の 目的:
- 極地氷床の融解が将来の海面に達する可能性がある脅威を評価する.
- グリーンランドと南極の氷床の脆弱性を評価する.
主な方法:
- 氷河期間の古気候データの分析.
- 過去の氷床の行動と海面の変化の再構築.
主要な成果:
- 2100年までに極地の温暖化は13万~12万7000年前に観測されたレベルに達する可能性がある.
- 過去の氷床の融解は,将来の急速な海面上昇の可能性を示しています.
- グリーンランドと南極の氷床は,潜在的に脆弱である.
結論:
- 将来の海面上昇は過小評価されている可能性があります.
- 気候変動とその影響が極地の氷床に及ぼす影響を軽減するために,緊急の行動が必要である.
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