グリーンランドの氷床が最後の氷期間の海面上昇に大きく貢献した
1Department of Geography, University of California, Berkeley 94720-4740, USA. kcuffey@socrates.berkeley.edu
Nature
|April 15, 2000
まとめ
グリーンランドの氷床は,エーミア期にはより小さく,より険しかったので,海面の上昇に大きく貢献した. これは,エミアンの海面が,西南極の氷床の融解によるだけではないことを示唆している.
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
- 気候科学 気候科学
背景:
- 氷河期間のエミアンの海水位は,現在の海水位より大幅に高かった.
- 以前のモデルでは,グリーンランドの氷床がエミアン海面上昇に与える影響は限られていると示唆されていた.
研究 の 目的:
- グリーンランドの氷床がエミアン海平面の上昇に与える影響を再評価する.
- 氷のコアデータと,氷床の行動に関する気候モデルを調和させるため.
主な方法:
- 氷床のダイナミクスの数値モデリング.
- グリーンランド中央部の最近の氷芯データの分析.
主要な成果:
- グリーンランドの氷床は,エーミア紀の間,より小さく,より険しかった.
- グリーンランドの溶融水は,エエム海の海面に4~5.5メートルを寄与したと考えられる.
- エイミアンの海面上昇は,グリーンランドの溶融水を大量に含んだ可能性が高い.
結論:
- Eemianの海水位は,グリーンランドの氷床の重要な貢献によって影響を受けました.
- 高いエミアン海水位は,必ずしも西南極の大規模な氷床の崩壊を暗示するものではありません.
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