The Gulf of Mexico and ENSO Influence on Subseasonal and Seasonal CONUS Winter Tornado Variability
The Gulf of Mexico and ENSO Influence on Subseasonal and Seasonal CONUS Winter Tornado Variability
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DOI：
10.1175/jamc-d-18-0046.1
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发表时间：
2018-10
影响因子：
3
通讯作者：
M. J. Molina;J. Allen;Vittorio A. Gensini
中科院分区：
文献类型：
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作者：
M. J. Molina;J. Allen;Vittorio A. Gensini
厄尔尼诺-南方涛动（ENSO）和墨西哥湾（GoM）影响冬季龙卷风的变化和显著的龙卷风（EF 2+，其中EF是增强的藤田尺度）环境。在拉尼娜期间，从大平原南部到中西部，以及在厄尔尼诺期间，美国南部毗连地区（CONUS）发生重大龙卷风环境的可能性增加。冬季显著的龙卷风环境是缺席整个佛罗里达，格鲁吉亚，和沿海卡罗莱纳州在中度到强烈的拉尼娜事件。在12月厄尔尼诺和1月拉尼娜期间，ENSO对急流的调制有助于增加龙卷风总数，特别是当与温暖的墨西哥湾同时发生时。ENSO中性阶段产生较少和较弱的龙卷风，但接近温暖的墨西哥湾气候特征可以提高显著龙卷风环境的可能性。厄尔尼诺/南方涛动强度问题;较强的ENSO阶段会增加龙卷风的频率和显著龙卷风环境的可能性，但其特点是方差很大，其中非常强的厄尔尼诺和拉尼娜事件会产生不利的龙卷风气候状态。这项研究表明，这是一个可行的事业，扩大春季季节性和亚季节性龙卷风预测的努力，包括冬季，这是非常重要的，因为冬季龙卷风构成的显着威胁。重大龙卷风占龙卷风死亡人数的95%，冬季龙卷风比其他季节更频繁。
El Niño–Southern Oscillation (ENSO) and the Gulf of Mexico (GoM) influence winter tornado variability and significant tornado (EF2+, where EF is the enhanced Fujita scale) environments. Increases occur in the probability of a significant tornado environment from the southern Great Plains to the Midwest during La Niña, and across the southern contiguous United States (CONUS) during El Niño. Winter significant tornado environments are absent across Florida, Georgia, and the coastal Carolinas during moderate-to-strong La Niña events. Jet stream modulation by ENSO contributes to higher tornado totals during El Niño in December and La Niña in January, especially when simultaneous with a warm GoM. ENSO-neutral phases yield fewer and weaker tornadoes, but proximity to warm GoM climate features can enhance the probability of a significant tornado environment. ENSO intensity matters; stronger ENSO phases generate increases in tornado frequency and the probability of a significant tornado environment, but are characterized by large variance, in which very strong El Niño and La Niña events can produce unfavorable tornado climatological states. This study suggests that it is a feasible undertaking to expand spring seasonal and subseasonal tornado prediction efforts to encompass the winter season, which is of importance given the notable threat posed by winter tornadoes. Significant tornadoes account for 95% of tornado fatalities and winter tornadoes are rated significant more frequently than during other seasons.