アジアから熱帯北太平洋への土壌塵の長距離大気輸送:時的変動性
まとめ
エネウェタク環礁の空気中の土壌塵の濃度は,1979年の5ヶ月間にわたって大幅に減少しました. おそらく中国からのこの塵は,北太平洋の深海沈殿物に大きく寄与する可能性がある.
科学分野:
- 大気科学 大気科学
- 海洋学 海洋学とは
- 地質化学 地質化学
背景:
- エネウェタク環礁は太平洋の遠隔地にあるため,大気圏の長距離輸送を監視するのに適した場所です.
- 空気中の塵の発生源と堆積率を理解することは,海洋沈殿物の構成と古気候記録の解釈に極めて重要です.
研究 の 目的:
- エネウェタク環礁の空気中の土壌塵の濃度と時間的傾向を定量化するために.
- 観測された塵の発生の潜在的な起源と堆積の重要性を調査する.
主な方法:
- 空気中の微粒子を収集し,土壌の塵の濃度について分析した.
- 粉塵濃度の時間的な傾向は,5ヶ月の期間で分析されました.
主要な成果:
- 1979年4月,エネウェタク環礁の空気中の土壌塵の濃度は2.3μg/m3で測定されました.
- 濃度は着実に低下し,1979年9月までに0.02μg/m3に達した.
- 堆積率は1000年に約0.3mmと推定された.
結論:
- エネウェタク環礁で観測された春の塵は,中国などの東アジアの源泉から発生した可能性が高い.
- 計算された堆積率は,この塵が北太平洋の深海堆積物に大きく寄与する可能性があることを示唆している.
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