中世の温暖期における大平原における大きな風移り
Venkataramana Sridhar1, David B Loope, James B Swinehart
1Department of Geosciences, University of Nebraska, Lincoln, NE 68588-0340, USA.
まとめ
ネブラスカ ネブラスカ ネブラスカ州
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
- ジオモルフォロジー ジオモルフォロジー
- 大気科学 大気科学
背景:
- 成長期の降雨はネブラスカ州サンドヒルズの草原の草木を維持し,砂丘の移動を防ぐ.
- 縦断的な砂丘は,特に中世の温暖期 (MWP) の間に,砂の移動の過去の期間を示しています.
研究 の 目的:
- 中世の温暖期における砂丘形成に関連した古気候条件を再構築する.
- 大陸平原における干ばつと砂の移動につながる大気循環の変化を理解するために.
主な方法:
- オリエンテーションと横断層を含む砂丘の地形学的分析.
- 砂丘の記録に基づいた古気候の再構築.
主要な成果:
- MWPの砂丘は,双極のダイップ方向でNW-SE方向を向いており,特定の風向きを示しています.
- これらの砂丘の特徴は,湿った南風から乾燥した南西風へのシフトによって開始された重大な干ばつを記録しています.
結論:
- 中世の温暖期は,大平原の大規模な干ばつを経験し,大気循環の変化に関連した.
- 砂丘の記録は,この地域の過去の気候の変動と干ばつに関する重要な証拠を提供します.
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