Observed trends in the Great Plains low-level jet and associated precipitation changes in relation to recent droughts
Observed trends in the Great Plains low-level jet and associated precipitation changes in relation to recent droughts
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DOI：
10.1002/2013gl058296
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发表时间：
2013-12-16
影响因子：
5.2
通讯作者：
Hilburn, Kyle
中科院分区：
文献类型：
--
作者：
Barandiaran, Daniel;Wang, Shih-Yu;Hilburn, Kyle
最近大平原上的干旱对农业和经济产生了重大影响，突出表明需要更好地了解区域水文气候正在发生的任何变化。利用1979-2012年期间的北美区域再分析(NIR)分析了4-6月期间大平原低空急流(GPLLJ)和相关降水的趋势。计算的经向风和整个大平原的降水强度、频率和总量的线性趋势表明：(1)GPLLJ增强并向北扩展；(2)南部平原降水大幅减少，北部平原降水增加。特别是在俄克拉何马州-得克萨斯州地区的雨季5月，降水与GPLLJ北缘的移动相对应地向北迁移，导致自1979年以来降水量减少了近50%。这些观察到的变化是在最近的干旱和该区域预测的气候背景下讨论的。
Recent drought over the Great Plains has had significant impacts on agriculture and the economy, highlighting the need for better understanding of any ongoing changes in the regional hydroclimate. Trends in the Great Plains low-level jet (GPLLJ) during the months April-June and associated precipitation are analyzed using the North American Regional Reanalysis (NARR) for the period 1979-2012. Linear trends computed for meridional winds and precipitation intensity, frequency, and total across the Great Plains show that (1) the GPLLJ has strengthened and expanded northward and (2) precipitation has decreased substantially in the Southern Plains while increasing in the Northern Plains. Particularly in May, the rainy season in the Oklahoma-Texas region, precipitation has migrated northward in correspondence to the shifted northern edge of the GPLLJ, leading to near 50% declines in precipitation since 1979. These observed changes are discussed in the context of recent droughts and projected climate for the region.