ホロセンの初期,パイン・アイランド氷河の急速な薄まりは,ホロセンの初期に起きました
J S Johnson1, M J Bentley, J A Smith
1British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK.
まとめ
パイン・アイランド氷河は,ホロセンの初期に急速な薄まりを経験し,今日と同じです. 氷床の変化によって引き起こされたこの古代の氷の減少は,何世紀にもわたって持続し,長期の氷床の不安定性を強調しました.
科学分野:
- 氷河学 氷河学とは
- 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,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 西南極氷床の動態 西南極氷床の動態
背景:
- パインアイランド氷河 (Pine Island Glacier,PIG) は,西南極氷床の主要な出口氷河である.
- PIGは,過去20年間にわたり,著しい薄れと後退を示しています.
研究 の 目的:
- パイン・アイランド氷河の急速な薄くなりつつある過去を調査するためです.
- 初期のホロセンの薄くなる速度と,現代の変化を比較する.
主な方法:
- 氷河地質学データを活用した.
- 氷河で運ばれた岩石の年代測定に,地質年代測定技術,特に宇宙年代測定 (10) を採用した.
主要な成果:
- パイン・アイランド氷河は,ホロセンの初期,約8000年前に急速な薄まりを経験しました.
- 薄くする速度は年間100cmを超え,何十年も何世紀も持続した.
- この過去の希薄化は現在の速さと同等であり,氷床の補強が減ったことによって引き起こされている可能性が高い.
結論:
- パイン・アイランド氷河は,急速に薄くなり続けている歴史があります.
- この地域における氷床の急速な変化は,一度開始されれば,何世紀にもわたって持続し,長続きする可能性があります.
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