オトリートデルタ18Oは,ペルーのホロケーン期中期の海面温度の記録である
C Fred T Andrus1, Douglas E Crowe, Daniel H Sandweiss
1Department of Geology, University of Georgia, Athens, GA 30602-2501, USA. andrus@gly.uga.edu
まとめ
ペルーのホロセンの半ばの海面温度は,魚の耳石が示すように,より暖かかった. この温暖化傾向は,加強された上流とともに,過去の気候変化の洞察を提供します.
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
- マリン・バイオロジー マリン・バイオロジー
- イクチオロジー イクチオロジー
背景:
- 魚の耳石,特にペルーの海猫魚 (Galeichthys peruvianus) のサギタルの耳石は,過去の環境条件を再構築するための貴重なアーカイブとして機能します.
- オトーリフの酸素同位体分析は,過去の海面温度 (SST) を決定するためのプロキシを提供します.
研究 の 目的:
- ペルー沖のホロセーン中期の海面温度 (SST) を,魚の耳石の酸素同位体解析を用いて再構築する.
- 過去のSST,トロフィックレベル,および上流などの海洋学現象の間の潜在的な相関を調査する.
主な方法:
- 考古学遺跡 (オストラとシチェス) のペルーの海猫魚 (Galeichthys peruvianus) のサギタルオトリーフの発掘と分析.
- 過去のSSTを決定するために,オトリスの酸素同位体プロファイリング.
- トロフィックレベル,集団の多様性,および関連する動物集団からの公平性の分析.
主要な成果:
- オストラ (6010 +/- 90 yr B.P.) の耳石 夏のSSTは現在より約3°C暖かくなると示されています.
- シチェスの耳石 (6450 +/- 110 yr B.P.) 記録された年間平均気温は,現代の条件より3°Cから4°C暖かい.
- 生物のデータは同位体解釈を支持し,約5000年B.P.後のペルー・チリ流の上昇が強まったことを示唆した.
結論:
- ホロセンの中期,ペルーの沿岸海域は,現在の海面温度と比較して,海面温度が著しく上昇した.
- B.P. 5000年後のペルー・チリ流の上昇が強まった. おそらくこれらの温度変化に影響を与えた.
- 魚の耳石は,この地域の過去の海洋学および気候条件の信頼できる記録です.
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