プレオセンの古気候と東南極の氷床の歴史は,表面上の灰堆積から得られたものです
Science (New York, N.Y.)
|April 30, 1993
まとめ
アレナ・バレーでは430万年もの間,寒冷な砂漠の気候が持続しており,東南極の氷床を示しています.
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
- 地質学 地質学 地質学
- 南極研究南極研究
背景:
- 長期の気候の安定性を理解することは,温暖化に対する氷床の反応を予測するために極めて重要です.
- 過去の温暖な時期を通じて東南極氷床 (EAIS) の持続性は議論されている.
研究 の 目的:
- アレナ・バレー,ビクトリア・ランドの古気候を再現する.
- 東南極の氷床の長期的な安定性を評価する.
主な方法:
- in situの灰岩層と,その下にある砂漠の舗装の分析.
- ストラティグラフィック年代測定と保存分析.
主要な成果:
- アレナ・バレーでは,過去430万年以上にわたって,冷たい砂漠の気候が持続していたことを示す証拠があります.
- プレオセンの気温は,現在の気温よりわずかに高かった (≤3°C).
- 東南極の氷床は,この期間に安定した状態を保ちました.
結論:
- 東南極の氷床は,少なくとも430万年間存在している可能性が高い.
- 将来の温室効果温暖化によるEAISの大幅な崩壊は,プレオセンのような気温シナリオでもあり得ない.
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