AI 中文总结
该研究揭示厄尔尼诺期间热带中北太平洋次表层热含量变化抵消海表温度的有利作用，限制热带气旋生成，为热带气旋生成机制及未来预测提供关键依据。
AI 中文摘要
广阔的热带太平洋是每年威胁沿岸国家的多数热带气旋（TC）的发源地。热带气旋生成依赖于温暖的海表温度（SST）提供能量。在厄尔尼诺期间，西太平洋暖池会向东扩展，但热带气旋数量并未随暖池扩展显著增加，厄尔尼诺与拉尼娜期间的热带气旋数量仍相当。本文表明，热带中北太平洋的次表层热含量变化抵消了有利的海表温度作用：由于异常的正风应力旋度，厄尔尼诺期间该区域的26℃等温线上抬，尽管存在暖海表温度异常，热带中北太平洋的热含量仍有所减少。海表温度异常与26℃等温线深度异常之间的负相关关系，与热带东、西太平洋的正相关关系相反。量化次表层海洋的动力学对理解热带气旋生成至关重要，目前热带气旋生成的趋势仍存在争议，未来的预测必须考虑海表-次表层动力学对热带气旋的净效应，尤其是在全球变暖下热带太平洋预计会出现类厄尔尼诺型态的背景下。
英文摘要
The vast tropical Pacific is home to the majority of tropical cyclones (TCs) which threaten the rim countries every year. The TC genesis is nourished by warm sea surface temperatures (SSTs). During El Niño, the western Pacific warm pool extends eastward. However, the number of TCs does not increase significantly with the expanding warm pool and it remains comparable between El Niño and La Niña. Here, we show that the subsurface heat content change counteracts the favorable SSTs in the tropical central-north Pacific. Due to the anomalous positive wind stress curl, the 26 °C isotherm shoals during El Niño over this region and the heat content diminishes in the tropical central-north Pacific, even though warm SST anomalies prevail. This negative correlation between SST and 26 °C isotherm depth anomalies is opposite to the positive correlation in the tropical eastern and western Pacific. This is critical because quantifying the dynamics of the subsurface ocean provides insight into TC genesis. The trend in TC genesis continues to be debated. Future projections must account for the net effect of the surface-subsurface dynamics on TCs, especially given the expected El Niño-like pattern over the tropical Pacific under global warming.
Comments7 pages, 4 figures; published in Nature Communications
Journal refNature Communications 13, 7746 (2022)
DOI：10.1038/s41467-022-35530-9
