论文标题
预计欧洲概要循环的变化及其对夏季降水的影响：CMIP6观点
Projected changes in synoptic circulations over Europe and their implications for summer precipitation: A CMIP6 perspective
论文作者
论文摘要
夏季降水缺陷的预计变化部分取决于概要循环的改变。在这里，自动化的Jenkinson-Collison（JC）分类用于评估21个全球气候模型（GCMS）捕获重复循环类型（CTS）及其对夏季欧洲每日降水强度的影响的能力（JJA）。首先评估GCM重现观察到的当前气候特征的能力。大多数GCM捕获了观察到的CTS平均方向流量特征与干燥天数和相关干燥月份之间的联系。对于反气旋和东方CT的最强关系，这些关系通常与干燥条件的平均发生相关。为了高信噪比，在高排放SSP5-8.5方案中估算了CTS夏季频率的未来变化。我们的结果揭示了一致的变化，主要是在区域CTS中。西风的频率强劲下降，而东欧CTS的频率增加了中欧的大陆，干燥和温暖的空气质量。这些动态变化显示出可以增强中欧和南欧的预计夏季干燥。
Projected changes in summer precipitation deficits partly depend on alterations in synoptic circulations. Here, the automated Jenkinson-Collison (JC) classification is used to assess the ability of twenty-one Global Climate Models (GCMs) to capture the frequency of recurring circulation types (CTs) and their implications for European daily precipitation intensities in summer (JJA). The ability of the GCMs to reproduce the observed present-day climate features is first evaluated. Most GCMs capture the observed links between mean directional flow characteristics of the CTs, and the occurrence of dry days and related dry months. The most robust relationships are found for anticyclonic and easterly CTs which are generally associated with higher than average occurrences of dry conditions. Future changes in summer frequencies of the CTs are estimated in the high-emissions SSP5-8.5 scenario for the sake of a high signal-to-noise ratio. Our results reveal consistent changes, mainly in the zonal CTs. A robust decrease in frequency of the westerlies and increase in the frequency of easterly CTs favour more continental, dry and warm air masses over Central Europe. These dynamical changes are shown to enhance the projected summer drying over central and southern Europe.
