COVID-19 パンデミック ロックダウン対策により,高周波地震の騒音が地球規模で静まりました
Thomas Lecocq1, Stephen P Hicks2, Koen Van Noten3
1Seismology-Gravimetry, Royal Observatory of Belgium, Brussels, Belgium. thomas.lecocq@seismology.be.
Science (New York, N.Y.)
|July 25, 2020
まとめ
COVID-19のパンデミックは,人為的な地震騒音の記録的な減少を引き起こしました. 地下での微妙な信号と 人間の活動レベルを研究する 絶好の機会です
科学分野:
- 地理学
- 地震学
- 環境科学
背景:
- 人間の活動により 地震波が発生し 背景の地震騒音も発生します
- パンデミックの緩和措置は,地球規模の人間の活動に前例のない減少をもたらしました.
- 2020年の地震静寂期は,人類による地震騒音の減少が記録されている中で最も長く,最も顕著である.
研究 の 目的:
- パンデミックに関連した人間の活動の変化が地震騒音に与える影響を分析する.
- 地震静止期を活用して 地下地震信号を検出する
- 人々の移動をリアルタイムで 推定するツールとして 地震学を確立する
主な方法:
- 世界的な地震計ネットワークからの地震騒音データの分析.
- パンデミック静寂期間の地震騒音レベルと過去のデータとの比較.
- 地震騒音の減少と人間の移動能力の指標との相関関係
主要な成果:
- 地震騒音の減少は,世界的に50%まで観察されました.
- 地震の静寂は 人口のある地域から 放射的距離と深さに大きく広がった.
- 地震騒音と人間の移動能力のデータには強い相関関係があることが判明した.
結論:
- COVID-19 パンデミックは,地震の騒音の軽減に関するユニークな大規模な実験を提供しました.
- 地震騒音の減少は,微妙な地震信号の検出性を向上させ,騒音源のベンチマークを助ける.
- 地震騒音は 人間の活動レベルを リアルタイムで 確実に示すものです
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