チリ北部のアタカマ砂漠のモンスーンの降雨の2万2000年の記録
1U.S. Geological Survey, 1675 West Anklam Road, Tucson, AZ 85745, USA. Laboratorio de Botanica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile. Department of Geosciences, University of Arizona, Tucson, AZ 85721, USA.
Science (New York, N.Y.)
|September 1, 2000
まとめ
古代のアタカマ砂漠は,過去の氷河期に降雨量と植生が増えた経験があり,以前の気候モデルに挑戦しました. これは,複雑なグローバルな気候のつながりが,地域の降雨パターンに影響を与えたことを示唆している.
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
- 気候科学 気候科学
背景:
- 中央のアタカマ砂漠の過去の気候は,特に世界的な気候変動の時期に,ほとんど理解されていません.
- 過去の降水パターンを理解することは,乾燥地域における将来の気候シナリオを予測するために極めて重要です.
研究 の 目的:
- 化石の証拠を用いて,中央アタカマ砂漠の過去の気候条件を再構築する.
- 過去の降水変化の原動力とその関係と地球温暖化への影響を調査する.
主な方法:
- 化石歯類のミッドと湿地の堆積物の分析.
- 放射性炭素年代測定法により,年代的枠組みを確立する (紀元前16.2~3千年前). ) を実施する.
- 植生覆面と地下水のレベルの再構築.
主要な成果:
- 夏の降雨量,草地,地下水の増加が16.2から10.5kB.P.に増加した証拠があります.
- 茂みと草の上昇は,現在乾燥している地域へと広がった.
- 8〜3kB.P.の後の,より顕著な湿気期間のB.P. チティカカ湖のデータと矛盾している.
結論:
- アタカマ砂漠の過去の雨期は,北半球の太陽照射,アジアのモンスーン,太平洋の海面温度の間のテレコネクションと関連している可能性があります.
- 夏の低日当たりの雨季のパラドックスなタイミングは,複雑な気候のダイナミクスを示唆しています.
- 古気候記録の不一致 (アタカマとチチカカ湖) は,気候変動に対する地域的な反応の多様性を強調しています.
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