北米中部におけるエオセン・オリゴセンの移行期にわたる大きな気温低下
Alessandro Zanazzi1, Matthew J Kohn, Bruce J MacFadden
1Department of Geological Sciences, University of South Carolina, Columbia, South Carolina 29208, USA. azanazzi@geol.sc.edu
Nature
|February 9, 2007
まとめ
エオセン・オリゴセンの移行期には,40万年以上にわたって大陸の8.2°Cの冷却が顕著になり,爬虫類や両生類には影響したが,哺乳類には影響しなかった. この気候の変化は,大気中の二酸化炭素の減少によって引き起こされた可能性が高い.
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
- パレオントロジー・パレオントロジー
- 地質化学 地質化学
背景:
- エオセノ・オリゴセノ移行期 (約. 3350万年前) は,ケノゾイク期の大規模な冷却イベントを記した.
- 海洋気候記録はよく研究されているが,大陸の変化はあまり理解されていない.
- 以前の研究は,大陸の気候変化のタイミングと規模に関する矛盾したデータをもたらした.
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