The Effects of Snow Cover on Midlatitude Cyclones in the Great Plains
The Effects of Snow Cover on Midlatitude Cyclones in the Great Plains
复制标题
积雪对大平原中纬度气旋的影响
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
D. Leathers
中科院分区：
文献类型：
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作者：
N. Elguindi;B. Hanson;D. Leathers
本文研究了积雪对中纬度气旋结构和强度的影响。第五代宾夕法尼亚州立大学-国家大气研究中心（宾夕法尼亚州立大学-NCAR）中尺度模式（MM 5）被用来模拟8个天气事件，其中一个发展良好的气旋移动通过美国中部和北方大平原地区。每个事件进行了两次模拟：一次是实际积雪覆盖的控制运行，一次是大范围积雪覆盖的扰动运行。在所有的情况下，增加积雪，从而减少可用的势能，削弱了气旋。在这八个例子中，扰动运行中的气旋的平均最小中心低压比控制气旋大约4毫巴。低层大气温度和湿度的降低在暖区最为明显，这大大降低了地表附近的温度和湿度梯度。这导致了...
Abstract The impacts of snow cover on the structure and intensity of midlatitude cyclones are examined. The fifth-generation Pennsylvania State University–National Center for Atmospheric Research (Penn State–NCAR) Mesoscale Model (MM5) was used to simulate eight synoptic events in which a well-developed cyclone moved across the central and northern Great Plains region of the United States. Two simulations were performed for each event: a control run with the actual snow cover and a perturbed run with an extensive snow cover. In all of the cases, increasing the snow cover, and thereby reducing the available potential energy, weakened the cyclones. Among the eight cases, the averaged minimum central low pressure of the cyclones in the perturbed runs was approximately 4 mb greater than the control cyclones. The reduction in temperature and moisture in the lower atmosphere was most pronounced in the warm sector, which significantly reduced the thermal and moisture gradients near the surface. This resulted in ...