航空機による雲の穴の形成と広がり
Andrew J Heymsfield1, Gregory Thompson, Hugh Morrison
1National Center for Atmospheric Research (NCAR), Boulder, CO 80301, USA. heyms1@ncar.ucar.edu
まとめ
航空機の排気は,雲に大きな穴や運河を作ることができます. これらの氷粒子は垂直運動を誘導し,空港の近くで地域的に降水量を増加させる可能性があります.
科学分野:
- 大気科学 大気科学
- クラウド物理学 クラウド物理
- 航空気象学 航空気象学
背景:
- 穴穴と運河雲は50年以上前から観測されています.
- これらの雲の形成のメカニズム,発展,および持続期間は,依然として十分に理解されていない.
- これまでの研究は,その影響の範囲をほとんど見過ごしていた.
研究 の 目的:
- 航空機によって引き起こされる雲の穴や運河の形成と進化に起因するメカニズムを調査する.
- これらの現象に関連した持続時間と垂直運動効果を分析する.
- これらのクラウド改変の地域的およびグローバルな影響を評価する.
主な方法:
- モデルシミュレーションを使用して,氷粒子の成長と雲の動態を研究しました.
- 航空機による雲滴の自発的な凍結につながる条件を分析した.
- 航空機の部品に対する空気流が氷の形成に及ぼす影響を調べました.
主要な成果:
- 航空機によって生成された氷粒子は,1時間以上持続する垂直運動を開始することができます.
- これらの垂直運動は,雲の穴や運河の膨張に寄与する.
- グローバルな影響は最小限ですが,主要空港の近くでは地域の降水量が増加することが可能です.
結論:
- 航空機の排気は,無意識に雲の種を蒔き,穴や運河の形成につながります.
- 氷粒子の成長とそれに続く垂直運動は,これらの特徴の発達に重要な役割を果たしています.
- 地域的には,これらの現象は,特に空港の周辺では,追加の降雨を誘導することができます.
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