Arctic influence on subseasonal midlatitude prediction
Arctic influence on subseasonal midlatitude prediction
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北极对次季节中纬度预测的影响
DOI：
10.1002/2014gl059961
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发表时间：
2014
影响因子：
5.2
通讯作者：
S. Serrar
中科院分区：
文献类型：
--
作者：
T. Jung;M. Kasper;T. Semmler;S. Serrar
利用欧洲中期天气预报中心模式进行了预报实验，在有和没有北极对流层对再分析数据松弛的情况下，进行了预报实验，以探索冬季改进的北极预报对北半球中纬度500 hPa位势高度的中期和扩展范围预报技巧的影响。结果发现，中纬度地区最大的改善出现在东欧、北亚和北美；在北大西洋和北太平洋没有发现明显的影响，在那里中纬度和热带动力似乎更重要。发现北极和中纬度地区之间的联系强度依赖于气流，反常的北风导致更强的北极影响。最后，在北极海冰减少可能对中纬度天气和气候产生影响的背景下讨论了这些结果。
Forecast experiments with the European Centre for Medium‐Range Weather Forecasts model with and without relaxation of the Arctic troposphere toward reanalysis data are carried out in order to explore the influence that improved Arctic forecasts during wintertime would have on the skill of medium‐range and extended‐range prediction of 500 hPa geopotential height in the Northern Hemisphere midlatitudes. It turns out that the largest midlatitude improvements are found over eastern Europe, northern Asia, and North America; no discernible impact is found over the North Atlantic and North Pacific, where midlatitude and tropical dynamics appear to be more important. The strength of the linkage between the Arctic and the midlatitudes is found to be flow dependent, with anomalous northerly wind leading to a stronger Arctic influence. Finally, the results are discussed in the context of the possible impact of Arctic sea ice decline on midlatitude weather and climate.