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Assembly of Complex Microtubule Structures
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地中海の冬の降雨は,過去136万年の間,アフリカのモンスーンと相乗っている
Bernd Wagner1, Hendrik Vogel2, Alexander Francke3,4
1Institute of Geology and Mineralogy, University of Cologne, Cologne, Germany. wagnerb@uni-koeln.de.
Nature
|September 4, 2019
まとめ
地中海の冬は,季節的な太陽光と強いアフリカのモンスーンの時期に湿りやすい. このパターンは海面温度に左右され 過去の降雨を復元し 気候モデルをテストするのに役立ちます
科学分野:
- 古代気候学
- 気候の動態
- 地中海水候
背景:
- 地中海の気候は,社会経済的な要因に決定的な季節的な降雨の変動を示しています.
- 冬の降雨の変化の正確なシミュレーションと四季期の再構築は,希少な長期の水気気候記録のために困難です.
- 水候変動のメカニズムと持続性の理解は限られている.
研究 の 目的:
- 過去136万年の地中海冬の降雨の変動を再構築する.
- この地域の湿った冬を駆動する 根本的なメカニズムを探る
- 気候モデルのパフォーマンスの基準となる.
主な方法:
- オフリッド湖のプロキシ・タイムシリーズの分析
- 78万4千年の気候モデルを使って
- 現代の再分析データとの比較
主要な成果:
- 北中地中海の湿った冬は,高季節の太陽照射のコントラストと,過去136万年にわたる強いアフリカの夏季モンスーンと相関しています.
- 海面温度上昇は局所的なサイクロン発生を拡大し,特定の氷河期と氷河期間の北大西洋システムに影響を与えます.
- 再構築された降雨誘導体は現在の降雨パターンと類似しています.
結論:
- この研究は,湿った冬と特定の軌道とモンスーンの条件を結びつけ,地中海の長期水候記録を確立しています.
- 発見は,海面温度が地中海冬の降雨を調節する上で重要な役割を果たすことを示唆しています.
- このデータは気候モデルを検証する際の 重要な基準となるもので,特に 軌道の強迫が変化する期間のデータです.
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