西南極の海面指紋は崩壊している
Jerry X Mitrovica1, Natalya Gomez, Peter U Clark
1Department of Physics, University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7, Canada.
Science (New York, N.Y.)
|February 7, 2009
まとめ
西南極の氷床の崩壊による海面上昇は,予想以上に高くなることがあります. 新しい研究によると,米国の沿岸地域は,これまで予想されたことより2〜3倍もの海面上昇を経験する可能性がある.
科学分野:
- 気候科学 気候科学
- 氷河学 氷河学とは
- 海洋学 海洋学とは
背景:
- 西南極の氷床の崩壊後の現在の海面上昇予測は,均一な溶融水の分布を想定しています.
- 1977年の研究では,北太平洋と米国の海岸線で局所的なより高い海面上昇が示唆されましたが,これはほとんど見過ごされています.
- 既存のモデルでは,氷床の融水が地域の海面に与える影響を過小評価している可能性がある.
研究 の 目的:
- 西南極の氷床が崩壊した後の海面上昇予測を,高度な理論モデルを使用して再評価する.
- 均一 (ユースタティック) の分布を超えた米国の海岸線に沿った海面上昇の可能性を定量化するために.
- 1977年の研究を含む以前の推定値と新しい予測を比較する.
主な方法:
- 海面変化に関する最先端の理論的枠組みの適用.
- 崩壊した西南極の氷床から溶けた水の空間的分布をモデル化.
- ユースタティック上昇に相対した予測された海面異常の分析.
主要な成果:
- ユースタティック値を超える海面上昇は,以前に推定されたものより大幅に高くなると予測されています.
- 米国沿岸地域の海面上昇は,以前の予測の2~3倍になると予測されています.
- これらの発見は,氷床の融解に対する海平面の反応における実質的な地域的変動を強調しています.
結論:
- 海面上昇予測では,融水分布の不均一性,特に脆弱な海岸線を考慮する必要がある.
- 西南極の氷床の崩壊が米国の海面に及ぼす影響は,現在のモデルによってかなり過小評価されている可能性があります.
- 地域の海平面の動態に関するさらなる研究は,正確な気候変動適応計画に不可欠です.
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