マヤの低地における干ばつ頻度に対する太陽の影響
D A Hodell1, M Brenner, J H Curtis
1Department of Geological Sciences, University of Florida, Gainesville, FL 32611, USA. dhodell@geology.ufl.edu
Science (New York, N.Y.)
|May 19, 2001
まとめ
湖の堆積物分析は,ユカタンで208年間の干ばつサイクルが太陽活動と関連していることを明らかにしています. この太陽の力は古代マヤ文明に影響を与え,文化的変化と相関していた.
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
- 考古学考古学とは
- ソーラー物理学 ソーラー物理学
背景:
- 過去の気候の再構築は,長期的な環境と社会的動態を理解するために不可欠です.
- ユカタン半島には,マヤを含む古代文明の豊かな歴史があり,その発展は地域的な気候の変動によって影響を受けた可能性が高い.
研究 の 目的:
- ユカタン半島の気候の歴史を過去2600年にわたって再構築する.
- 地域の干ばつにおける周期的なパターンとその潜在的な要因を特定する.
- 気候の振動とマヤ文化の進化との相関を調査する.
主な方法:
- ユカタン半島からの湖沈殿体コアの分析.
- 酸素イソトープや石膏の降水を含む堆積物のプロクシーのタイムシリーズ分析により,蒸発-降水比を追跡できます.
- 特定された干ばつ周期を,太陽活動指標としての宇宙原核化物 (炭素-14とベリリウム-10) の生産記録と比較した.
主要な成果:
- ユカタンの気候記録では,208年の支配的な周期性を持つ繰り返しの干ばつパターンが特定されました.
- この208年周期は,宇宙原核素生成で観測された206年周期と密接に一致しており,太陽活動変動との関連を示唆しています.
- 208年間の干ばつサイクルにおける特定のピークは,マヤ文化発展の記録された混乱と一致しています.
結論:
- ソーラーフォースは,ユカタンの干ばつにおける世紀のスケールの変動を説明する重要な要因です.
- 太陽の活動に起因する二百年にわたる降雨の振動は,古代マヤ人に影響したと思われる.
- 気候の変動は,マヤ文明の軌道を形作る上で重要な役割を果たしました.
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