2024-02-05 パシフィック・ノースウェスト国立研究所(PNNL)
◆研究者たちは、第六期結合モデル相互比較プロジェクト(CMIP Phase 6)からのデータを用いて、太平洋北西部の反サイクロニックな停滞波循環の変化を調べ、それらの変化を停滞波モデルを用いて診断しました。
◆研究結果から、将来の熱波リスクの増加に対する重要な要因であるヒートドームのような停滞波の変化が明らかになりました。
＜関連情報＞
- https://www.pnnl.gov/publications/stationary-heat-waves-likely-increase
- https://www.nature.com/articles/s41612-023-00511-2
北米北西部における夏のヒートドーム状定常波の増加予測 Projected increase in summer heat-dome-like stationary waves over Northwestern North America
Ziming Chen,Jian Lu,Chuan-Chieh Chang,Sandro W. Lubis & L. Ruby Leung
npj Climate and Atmospheric Science Published:21 November 2023
DOI:https://doi.org/10.1038/s41612-023-00511-2
Abstract
Heat-dome-like stationary waves often lead to extreme heat events, such as the unprecedented heatwave in Northwestern North America during the summer of 2021. However, future changes in summer stationary waves over Northwestern North America and the underlying driving factors remain unclear. Here, we investigate the projected changes in the anticyclonic stationary wave circulation over Northwestern North America using data from the Coupled Model Intercomparison Project Phase 6 and diagnose the circulation changes using a stationary wave model. Our findings reveal a significant 95% increase in the summer stationary wave amplitude over Northwestern North America under the high-emission scenario in 2080–2099 relative to 1995–2014. The response is mainly driven by the diabatic heating changes over the tropical Pacific which induce a Rossby wave source in the northeastern tropical Pacific, and further supported by a northward expanded waveguide in North America, both enhancing wave activity flux into the Northwestern North America. The heat-dome-like stationary wave anomaly is expected to heighten the heatwave risk over the region.
