ハインリッヒ現象中の混合層の深化:多プランクトン型ホルマニフェラルデルタ18Oのアプローチ
Harunur Rashid1, Edward A Boyle
1College of Marine Science, University of South Florida, 140 7th Avenue South, St. Petersburg, FL 33701, USA. hrashid@marine.usf.edu
まとめ
ハインリッヒ現象として知られる,氷河期間の極端な気候の変動は,より深い海の混合を引き起こした可能性があります. これは,嵐が増加し,海洋上部の溶融水の垂直混合が強化されたことを示唆しています.
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
- 海洋学 海洋学とは
- 気候科学 気候科学
背景:
- 最後の氷河期のサイクルには,氷上ラフティングが顕著なハインリッヒ現象を含む極端な気候変動が特徴でした.
- 以前の研究では,これらの気候の変動を記録するために,氷芯と海洋沈殿物を利用しました.
研究 の 目的:
- ハインリッヒ現象の時の上部海洋状態を,プランクトン型フォラミニフェラ酸素同位素を用いて調査する.
- これらの極端な気候期間中に混合層の深さの変化が起こったかどうかを判断するために.
主な方法:
- 北大西洋の沈殿体コアからのプランクトンフォラミニフェラの酸素同位体変動の分析.
- 混合層と熱クリンに生息する類の同位体データを比較.
- フォアミニフェラルデータと氷芯と沈殿芯のプロキシとの相関.
主要な成果:
- 同様の酸素同位体変異は,ハインリッヒ事件0,1,4の間に3つのフォラミニフェラル分類体で観察されました.
- これらの変異は,同質化された上部水柱の同様の温度でカルシフィケーションが起こったことを示唆しています.
- 証拠は,ハインリッヒ事件の際に,特に氷河流出による破片帯域で,より深い表面混合層があったことを示している.
結論:
- ハインリッヒ現象は,北大西洋のより深い表面混合層と関連していました.
- ハインリッヒ事件の嵐の増加は,おそらく垂直の海洋の混合を強めた.
- この濃縮された混合は,上層の水柱を均質化し,海洋生態系と気候のダイナミクスに影響を与えました.
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