アラスカ南東部の若いドライアが記録されている可能性もある
Science (New York, N.Y.)
|December 7, 1990
まとめ
アラスカの氷河湾は,約10,800年前,ヤング・ドライアスに似た,深刻な気候の冷却イベントを経験しました. この気候変動は,地元の植生に重大な変化をもたらし,土壌の侵食が増加し,広範囲にわたる気候の混乱を示唆しました.
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
- 四次地質学 四次地質学
- パリノロジーはパリノロジーの学科です.
背景:
- ユング・ドライアスのイベントは,北大西洋地域における重要な寒冷期を表しています.
- 過去の気候現象の地球規模を把握することは,将来の気候変動を予測する上で極めて重要です.
研究 の 目的:
- アラスカ南東部の気候の冷却現象の証拠を調査するために,若いドライアスに匹敵する.
- この出来事に関連した古植生と環境の変化を再構成する.
主な方法:
- アラスカの氷河湾の湖の堆積物核の分析.
- 過去の植物の組成を決定するための花粉の分析.
- 土壌の浸食と有機物質の損失を評価するために堆積物の地化学分析.
主要な成果:
- ストラティグラフィック記録は,アラスカの氷河湾の冷却イベントが,若いドライアスと同期していることを示しています.
- 化石の花粉は,約10,800年前に松の木の公園からツンドラ植生への移行を明らかにし,9,800年前まで続いた.
- 地化学データは,この期間中に土壌有機物質の減少と鉱物浸食の増加を示しています.
結論:
- アラスカ南東部は,若干期の気候の冷却イベントを経験しました.
- この出来事は,氷河湾地域における重要な植生変化と侵食の増加をもたらした.
- この発見は,北大西洋の気候の混乱が半球全体に広がる可能性を示唆しており,さらなる調査が必要である.
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