The effect of domain size on the relationship between circulation type classifications and surface climate
The effect of domain size on the relationship between circulation type classifications and surface climate
复制标题
域大小对环流类型分类与地表气候关系的影响
DOI：
10.1002/joc.3688
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
F. Streicher
中科院分区：
文献类型：
--
作者：
C. Beck;A. Philipp;F. Streicher
环流类型分类（ctc）解析地表气候和环境变量的能力对于其在天气气候学应用中的应用至关重要。这种“概要技巧”取决于几个因素，包括分类方法的固有特性，以及不同的边界条件。在这个贡献的相关性的空间域的大小，为ctc是派生的进行了调查。为此，将不同的自动化ctc应用于1950-2010年的每日网格化海平面压力数据，在每种情况下，分布在北大西洋欧洲区域的44个地点的八个不同大小的空间域。对于由此产生的7000多个ctc，使用不同的评估指标估计了来自E - OBS v4.0数据集的日温度和降水的天气技能。根据不同的领域大小汇总的评估指标的结果值揭示了领域大小对ctc的概要技能的明显影响。一般来说，在水平维度约为1300-1800公里（东西方向）的领域规模似乎达到了最高的技能，因此涵盖了天气尺度系统最常见的规模范围。然而，夏季（与冬季相比）和更多大陆区域（与更多海洋区域相比）的降水（与温度相比）的最佳域大小往往更小。对于高于或低于某些阈值的温度，相对较小的最佳域的总体发现出现了明显的偏差，在某些地点和季节，大陆尺度域产生最高的天气学技能。最后，不同CTCs关于领域大小对综合技能影响的比较显示了方法之间的显著差异，并且清楚地阐明了可归因于不同领域大小的综合技能差异与与不同方法相关的差异达到相当的程度。
The ability of circulation type classifications (CTCs) to resolve surface climatic and environmental variables is essential with respect to their application in synoptic climatological applications. This ‘synoptic skill’ depends on several factors including inherent properties of classification methods but as well varying boundary conditions. In this contribution the relevance of the size of the spatial domain for which CTCs are derived is investigated. To this end varying automated CTCs are applied to daily gridded sea level pressure data for 1950–2010 and in each case eight spatial domains of varying size centred around 44 locations spread over the greater north Atlantic European region. For the resulting more than 7000 CTCs the synoptic skill for daily temperature and precipitation taken from the E‐OBS v4.0 data set has been estimated using varying evaluation metrics. Resulting values of evaluation metrics aggregated according to varying domain sizes reveal a distinct influence of the size of the domain on the synoptic skill of CTCs. In general highest skill appears to be achieved for domain sizes with a horizontal dimension of roughly 1300–1800 km (in west–east direction) thus covering most frequent size ranges of synoptic scale systems. However, optimal domain sizes tend to be smaller for precipitation (compared to temperature) in summer (compared to winter) and in more continental regions (compared to more oceanic regions). Distinct deviations from the overall finding of relatively small optimal domains emerge for temperatures above/below certain thresholds for which in certain locations and seasons continental scale domains yield highest synoptic skill. Finally the comparison of varying CTCs concerning the effect of the domain size for synoptic skill shows marked differences between methods and moreover clearly elucidates that differences in synoptic skill that can be attributed to varying domain sizes reach comparable magnitude than those related to differing methods.