ハンガ・トンガ・ハアパイ噴火による地表から宇宙への大気波
Corwin J Wright1, Neil P Hindley2, M Joan Alexander3
1Centre for Space, Atmospheric and Oceanic Science, University of Bath, Bath, UK. c.wright@bath.ac.uk.
Nature
|June 30, 2022
まとめ
2022年のHunga Tonga-Hunga Ha'apai噴火は,Lamb波や重力波を含む前例のない大気波を生み出し,地球を何度か回りました. この火山の出来事は 大気科学にとって ユニークな自然実験です
科学分野:
- 大気科学
- 地理学
- 火山学
背景:
- 2022年1月のHunga Tonga-Hunga Ha'apai噴火は,非常に爆発的な火山事件でした.
- 50km以上の高さに達した火山の羽根を生成した.
- 噴火によって 大気波が広がり かつてない現象です
研究 の 目的:
- ハンガ・トンガ・ハパイの噴火による 地球規模の大気波の反応を詳細に説明します
- 地球の表面からイオノスフィアまでの波の特性を定量化します
- 噴火を大気動態の 自然実験として分析する
主な方法:
- 衛星と地上からの観測を 活用した.
- 大気波の伝播速度とパターンを分析した.
- 火山の噴火から放出された熱を定量化した.
主要な成果:
- ラーム波や重力波を含む 大気波の幅広いスペクトルを観測した.
- 表面 (318.2±6 m/s) と平流 (308±5〜319±4 m/s) で測定されたラム波速度.
- ストラトスフィアの重力波の速度は 238 ± 3 と 269 ± 3 m/s の間で記録されています.
- この単一の源から地球全体に広がる 亜イオノスフィアの重力波
- 12時間以上にわたって 重力波の主要な源は 羽根からの潜在的熱の放出でした
結論:
- ハンガ・トンガの噴火は 世界規模でユニークな 大気波の反応を引き起こしました
- 観測された重力波と その速度は前例のないものです
- 噴火は突然の変化に対する 大気反応を理解するための 重要な自然実験として機能します
- 発見は天気と気候モデルの改善に役立ちます.
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