The influence of synoptic airflow on UK daily precipitation extremes. Part I: Observed spatio-temporal relationships
The influence of synoptic airflow on UK daily precipitation extremes. Part I: Observed spatio-temporal relationships
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DOI：
10.1007/s00382-009-0710-9
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发表时间：
2009
期刊：
影响因子：
4.6
通讯作者：
D. Maraun;T. Osborn;H. Rust
中科院分区：
文献类型：
--
作者：
D. Maraun;T. Osborn;H. Rust
我们利用 689 个雨量计观测到的时间序列，研究了天气尺度大气环流对英国极端日降水量的影响。为此，我们采用统计模型，使用气流强度、方向和涡度作为月降水量最大值广义极值分布的预测因子。推断出的关系与主要西风流、地形和周围海洋的水分供应有关。我们将各个雨量计的结果汇总到区域尺度，以研究极端降水的时间变化。气流解释了亚年到十年时间尺度上的很大一部分变化。 20世纪80年代和90年代苏格兰北部特别强的冬季降水很大一部分可归因于北大西洋涛动盛行的正相位。我们的统计模型可用于统计降尺度并验证区域气候模型的输出。
We study the influence of synoptic scale atmospheric circulation on extreme daily precipitation across the United Kingdom, using observed time series from 689 rain gauges. To this end we employ a statistical model, that uses airflow strength, direction and vorticity as predictors for the generalised extreme value distribution of monthly precipitation maxima. The inferred relationships are connected with the dominant westerly flow, the orography, and the moisture supply from surrounding seas. We aggregated the results for individual rain gauges to regional scales to investigate the temporal variability of extreme precipitation. Airflow explains a significant fraction of the variability on subannual to decadal time scales. A large fraction of the especially heavy winter precipitation during the 1980s and 1990s in north Scotland can be attributed to a prevailing positive phase of the North Atlantic Oscillation. Our statistical model can be used for statistical downscaling and to validate regional climate model output.