2023-09-05 ニューサウスウェールズ大学(UNSW)
◆研究によれば、海洋熱波は表面だけでなく海底にも影響を及ぼし、生態系に深刻な被害をもたらす可能性があります。また、海洋熱波は異なるタイプで発生し、季節によって異なる特性を持つことが判明しています
◆海洋温暖化を緩和するためには温室効果ガスの排出を減少させる必要がありますが、海洋熱波の影響を軽減する戦略を見つけるためにもこの知識が重要です。
＜関連情報＞
- https://newsroom.unsw.edu.au/news/science-tech/marine-heatwaves-don%E2%80%99t-just-hit-coral-reefs-they-can-cause-chaos-seafloor
- https://www.nature.com/articles/s43247-023-00966-4
オーストラリア東部沿岸海域における海洋熱波の海面下構造を制御する季節成層と複雑な局所ダイナミクス Seasonal stratification and complex local dynamics control the sub-surface structure of marine heatwaves in Eastern Australian coastal waters
Amandine Schaeffer,Alex Sen Gupta & Moninya Roughan
Communications Earth & Environment Published:01 September 2023
DOI:https://doi.org/10.1038/s43247-023-00966-4
Abstract
Marine heatwaves are extreme seawater temperature events that can have severe impacts on marine life. The extent of the ecological damage depends not only on the easily observed surface signature but on the marine heatwave structure at depth. However, due to a paucity of in situ sub-surface observations the vertical structure of marine heatwaves is poorly understood. Here we analyse the sub-surface coherence and controls of marine heatwaves using one of the world’s longest (28 years) records of daily sub-surface ocean temperature off Sydney, Australia. We show that seasonal stratification, large-scale circulation and local downwelling processes control the vertical coherence of coastal marine heatwaves. We define three classes of marine heatwaves which can extend through the water column, form in the shallow surface layer, or sub-surface independently, and are therefore not always evident in surface data. We conclude that sub-surface data need to be considered in monitoring marine heatwaves in coastal areas where maximum biological damage is reported.
