氷床と固い地球の影響は,遠くの海平面の歴史に影響を与えています
Sophie E Bassett1, Glenn A Milne, Jerry X Mitrovica
1Department of Earth Sciences, University of Durham, Durham DH1 3LE, UK.
まとめ
最後の氷河期における海面変化モデルには不一致がありました. 高粘度下層マントルと南極の氷床の融水を組み込んだ新しいモデルは,これらの問題を解決し,気候のドライバーとして早期の南極の脱氷を支援しています.
科学分野:
- 地球科学 地球科学 地球科学
- 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
背景:
- 最後の氷河期最大期以降の海面変化の予測は不一致を示している.
- 氷河期後期 (14,0009,000年前) のタヒチ,ホーン半島,サンダ・シェルフからの観測は,以前のモデルと矛盾しています.
研究 の 目的:
- 後期氷河期の海面変化予測の不一致を解決するために.
- 海面の変化における氷河の同静的調整と南極の氷床の融解水の役割を調査する.
主な方法:
- 氷河の同静的調整モデルを開発した.
- 高粘度下層マントル (4 x 10^22 Pa s) が組み込まれました.
- 南極の氷床の融水パルスIA (~15メートルのユースタティック等価) の有意な貢献が含まれています.
主要な成果:
- このモデルは,予測された海面の変化と観測された海面の変化の間の不一致をうまく解決しました.
- 高い下層マントルの粘度と大量な南極の融水が重要な要因であった.
- この発見は,南極の早期かつ急速な脱氷に関する理論と一致している.
結論:
- 南極の早期の急速な脱氷は,最後の氷河期を終わらせる上で重要な役割を果たした.
- マントルの粘度と氷床の動力学の影響を受ける氷河の静態調整は,正確な海平面予測に不可欠です.
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