最後の氷河期の海面変動について
M Siddall1, E J Rohling, A Almogi-Labin
1Southampton Oceanography Centre, European Way, Southampton SO14 3ZH, UK. ms14@soc.soton.ac.uk
Nature
|June 20, 2003
まとめ
世界の海水位は,最後の氷河期に大きく変動した. 赤海の堆積物コアを用いた新しい研究は,海面の変化を最大35メートルまで明らかにし,氷の体積の変化のより明確なイメージを提供します.
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
- 海水面再建工事について
- 氷河期のサイクルダイナミクス
背景:
- ミレニアムスケールの気候変動が最後の氷河周期をマークしましたが,世界の海面と氷の量に及ぼす影響は完全に理解されていません.
- 珊瑚礁や深海の酸素同位体からの海面再構築には, +/-30 m または +/-1 °C の不確実性を含む制限があります.
研究 の 目的:
- 酸素同位体記録を用いて,赤海における水在留時間の歴史を再構築する.
- 過去47万年の世界の海平面のより正確な曲線を導き出すために.
- 急激な気候変動と海面変動の関係について調査する.
主な方法:
- 赤海の沈殿体核からの酸素同位体記録の分析.
- 赤海と世界海洋の間の水交換をシミュレートするために,水力モデルの適用.
- 水力モデルからスリープの深さと地球海面の導出.
主要な成果:
- グローバル海平面の再構築は, +/-12mの精度と,現在以前の70〜25 kyrの百年スケールの解像度で,新しいグローバル海平面再構築が生成されました.
- 海平面の変化は最大35メートルまで確認された.
- 海面の変化率は年間最大2cmに達し,急激な気候変化と一致しました.
結論:
- この研究は,高解像度で正確な海面記録を提供し,氷河のサイクルダイナミクスの理解を向上させます.
- 過去の氷河期に海面が大きく急激に変化し,気候の変動と直接関係があった.
- 赤海は,過去の地球海平面の再構築のための貴重なアーカイブとして機能しています.
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