まとめ
頻度の高い氷山の産卵周期は2000年から3000年ごとに発生し,グリーンランドと関連しています.
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 海洋学
- 氷河学 氷河学とは
背景:
- ハインリッヒ現象は,氷床から大量の氷が放出され,7,000〜10,000年ごとに発生します.
- Dansgaard-Oeschger現象は,グリーンランドの氷の核に記録された急速な気候振動です.
研究 の 目的:
- 北大西洋における氷山の産卵の頻度と同期性を調査する.
- 氷山の産卵,グリーンランドの気温の振動,海面の気温との関係を決定する.
主な方法:
- 北大西洋の高解像度深海コアの分析.
- 氷山切断のデータとグリーンランドの氷芯記録の相関関係 (ダンズガード-オシュガー事件).
- カルビングイベントのタイミングと海面温度データとの比較.
主要な成果:
- ハインリッヒ事件とは異なる,頻度の高い氷山の産卵サイクル (2000〜3000年間隔) を特定した.
- これらの産卵周期とグリーンランドのダンズガード・オシュガー (温冷) 振動との相関が示された.
- これらのサイクルの間,複数の源から同期的な氷の放出が観察されました.
- 産卵周期が海面の気温変動から切り離されていることを発見した.
結論:
- 大気中のメカニズムは,グリーンランド上空の気温の急速な振動を誘導した可能性が高い.
- この大気メカニズムは,複数の氷床から同期した氷山の産卵に影響を与えました.
- この発見は,ハインリッヒ現象から以前に理解されていたよりも,気候と氷床の変動がより頻繁に起こる様子を明らかにしています.
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