Changing Spatial Structure of Summer Heavy Rainfall, Using Convection-Permitting Ensemble
Changing Spatial Structure of Summer Heavy Rainfall, Using Convection-Permitting Ensemble
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DOI：
10.1029/2020gl090903
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发表时间：
2021-02-16
影响因子：
5.2
通讯作者：
Onof, Christian
中科院分区：
文献类型：
--
作者：
Chen, Yuting;Paschalis, Athanasios;Onof, Christian
从观测和气候模型模拟来看，次日极端降雨量都在加剧，但降雨事件空间结构的未来变化仍然存在很大的不确定性。这里，通过使用英国上空的两组（1980-2000年、2060-2080年）12个成员、长达20年的允许对流的集合模拟（2.2公里，每小时）来分析夏季强降雨特征的未来变化。我们研究了降雨事件的峰值强度、空间覆盖范围和速度将如何变化，以及这些变化如何共同影响不同空间尺度的每小时极值。我们发现，除了强降雨事件的加剧之外，所有三个次区域的空间范围都有增加的趋势，其中西北地区的空间范围扩大了49.3%。这些变化加剧了大多数空间尺度的极端强度增加（北方：30.2%-34.0%，南方：25.8%）。对于面积为 20-500 km(2) 的集水区，极端面积的增加尤其明显。
Subdaily rainfall extremes have been found to intensify, both from observations and climate model simulations, but much uncertainty remains regarding future changes in the spatial structure of rainfall events. Here, future changes in the characteristics of heavy summer rainfall are analyzed by using two sets (1980-2000, 2060-2080) of 12-member 20-year-long convection-permitting ensemble simulations (2.2 km, hourly) over the UK. We investigated how the peak intensity, spatial coverage and the speed of rainfall events will change and how those changes jointly affect hourly extremes at different spatial scales. We found that in addition to the intensification of heavy rainfall events, the spatial extent tends to increase in all three subregions, and by up to 49.3% in the North-West. These changes act to exacerbate intensity increases in extremes for most of spatial scales (North: 30.2%-34.0%, South: 25.8%). The increase in areal extremes is particularly pronounced for catchments with sizes 20-500 km(2).