EPICAドームCの氷芯から過去80万年にわたる塵-気候の結合
F Lambert1, B Delmonte, J R Petit
1Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
Nature
|April 4, 2008
まとめ
氷河期は,氷河間期とは異なり,塵の流れと南極の気温との強い関連を示しています. 寒い気候は,この塵-気温の相関関係を強化し,南極と低緯度の気候の間の結合が増加することを示唆しています.
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
- 大気科学 大気科学
- 地質化学 地質化学
背景:
- エオール層の塵は,地球の放射線バランスと海洋の栄養供給に影響を及ぼします.
- 氷河期と氷河期間の時間スケールにおける気候の変化は,塵の循環に影響を与える可能性があります.
研究 の 目的:
- 過去8つの気候サイクルにおける塵の流れと気候の関係を調査する.
- 氷河期における塵の発生を制御する要因を理解する.
主な方法:
- 東南極のEPICAドームC氷芯からのエオール塵の高解像度分析.
- 塵流量記録と南極の気温記録の比較.
主要な成果:
- 塵の流れと気温の間の有意な相関は,氷河期間にみられたが,氷河間期にはみられなかった.
- 気候の冷却に伴い,南極の気温と塵の流れの相関は増加した.
- 大気中の輸送時間における限られた変化は,塵の源と寿命が,高氷河塵の投入の鍵であることを示唆しています.
結論:
- この研究は,南極と低緯度の気候が,より寒い条件と徐々に結合することを示唆しています.
- 氷河の塵の流れの増加は,南米の塵源の強化と,氷河期の水循環の縮小による大気中の塵粒子の寿命の延長に起因する.
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