Linkages between Extreme Precipitation Events in the Central and Eastern United States and Rossby Wave Breaking
Linkages between Extreme Precipitation Events in the Central and Eastern United States and Rossby Wave Breaking
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美国中部和东部的极端降水事件与罗斯比波浪破碎之间的联系
DOI：
10.1175/mwr-d-19-0047.1
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发表时间：
2019
影响因子：
3.2
通讯作者：
Bosart, Lance F.
中科院分区：
文献类型：
--
作者：
Moore, Benjamin J.;Keyser, Daniel;Bosart, Lance F.
使用1979-2015年极端降水事件（EPEs）和上层位涡（PV）流的气候学研究了美国中部和东部极端降水事件（EPEs）与天气尺度Rossby波破碎之间的联系。该调查分别集中在美国中部和东部的两个区域，并强调了广泛的EPE，即表现出异常大降水量的事件。PV流的相对频率被发现是显着增强相对于气候学立即上游的每个域在广泛的EPE。美国中部（~79%）和东部（~56%）大部分广泛分布的EPE与位于上游的PV流光同时发生。当PV流光发生在每个域的上游时，EPEs的比值比表明EPEs和Rossby波破碎之间存在强烈的统计学显著关联。EPE-Rossby波破碎链接的强度，共现分数和比值比测量，往往会增加EPE降水量的增加，这样最强的联系存在广泛的EPE。复合分析表明，Rossby波破碎可以导致广泛的EPE建立一个持久的高振幅天气尺度波型，其中强向极水汽输送和上升被迫在EPE区域的下游立即延长的上层槽。额外的分析表明，与相应的零的情况下，Rossby波破碎的情况下，广泛的EPE表现出显着更高的振幅波图案，有利于更大的极地运输的潮湿，条件不稳定的空气和更强的上升超过EPE区域。
Linkages between extreme precipitation events (EPEs) in the central and eastern United States and synoptic-scale Rossby wave breaking are investigated using 1979–2015 climatologies of EPEs and upper-level potential vorticity (PV) streamers. The investigation focuses on two domains over the central and eastern United States, respectively, and emphasizes widespread EPEs, events exhibiting exceptionally large precipitation volumes. The relative frequency of PV streamers is found to be significantly enhanced relative to climatology immediately upstream of each domain during widespread EPEs. Majorities of the widespread EPEs in the central (~79%) and eastern (~56%) U.S. domains co-occur with a PV streamer positioned immediately upstream. Odds ratios of EPEs for days when a PV streamer occurs upstream of each domain indicate a strong, statistically significant association between EPEs and Rossby wave breaking. The strength of the EPE–Rossby wave breaking linkage, as measured by co-occurrence fractions and odds ratios, tends to increase with increasing EPE precipitation volume, such that the strongest linkage exists for widespread EPEs. Composite analyses reveal that Rossby wave breaking can result in widespread EPEs by establishing a persistent high-amplitude synoptic-scale wave pattern, within which strong poleward water vapor transport and ascent are forced over the EPE region immediately downstream of an elongated upper-level trough. Additional analyses demonstrate that, compared to corresponding null cases, Rossby wave breaking cases resulting in widespread EPEs exhibit a significantly higher-amplitude wave pattern that favors greater poleward transport of moist, conditionally unstable air and stronger ascent over the EPE region.
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影响因子：
4.6
作者：
Sina Lenggenhager;O. Martius
通讯作者：
Sina Lenggenhager;O. Martius
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DOI：
10.1002/joc.3618
发表时间：
2013
期刊：
International Journal of Climatology
影响因子：
--
作者：
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通讯作者：
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DOI：
--
发表时间：
2007
期刊：
影响因子：
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作者：
P. Knippertz;Jonathan E. Martin
通讯作者：
Jonathan E. Martin
影响因子：
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作者：
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M. Sprenger;G. Fragkoulidis;Hanin Binder;M. Croci‐Maspoli;Pascal Graf;C. Grams;P. Knippertz;E. Madonna;S. Schemm;B. Škerlak;H. Wernli
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DOI：
--
发表时间：
2018
期刊：
影响因子：
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作者：
M. Röthlisberger;O. Martius;H. Wernli
通讯作者：
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