南極と北部の氷床からの氷河期の海面変化への同様の溶融水の貢献は,南極と北部の氷床からの氷河レベルの変化です
Eelco J Rohling1, Robert Marsh, Neil C Wells
1Southampton Oceanography Centre, Southampton SO14 3ZH, UK. e.rohling@soc.soton.ac.uk
Nature
|August 27, 2004
まとめ
最後の氷河期の間,南極と北半球の氷床は,海面上昇に等しく貢献しました. この研究は,両極域の溶融水の貢献を定量化しています.
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
- 海洋学 海洋学とは
背景:
- 7万5千年前から2万年前までの期間は,気候と海面の変動が顕著であった.
- 南大洋の氷河で覆われた残骸は,南極の融水が北部の氷床からの貢献とともに,海面の変化に影響を与えたことを示しています.
研究 の 目的:
- 南極と北部の氷床の融水が,海面の変化に与える相対的な貢献度を決定する.
- 溶融水の様々な放出が海洋の酸素同位体分布に与える影響をシミュレートする.
主な方法:
- 極地からの融水放出をシミュレートするために,中間的な複雑性モデルを使用しました.
- モデルのシミュレーションを,堆積物核からの酸素同位体データと比較した.
主要な成果:
- 6万5千年から3万5千年前の海面上昇に南極と北部の氷床がほぼ等しく貢献したと推論した.
- 各極域は,この期間中に海面上昇に15mの割合で貢献したと推定されています.
結論:
- この研究は,過去の海面変動時の融水源に関する定量的な洞察を提供します.
- 推論された南極の氷の量減少は,最後の脱氷期におけるメルトウォーターパルス1Aの減少に匹敵する.
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