Characteristics of sub-daily precipitation extremes in observed data and regional climate model simulations
Characteristics of sub-daily precipitation extremes in observed data and regional climate model simulations
复制标题
观测数据和区域气候模式模拟中次日极端降水的特征
DOI：
--
复制
发表时间：
2018
影响因子：
3.4
通讯作者：
M. Hanel
中科院分区：
文献类型：
--
作者：
R. Beranová;J. Kyselý;M. Hanel
该研究比较了在捷克共和国观测到的次日降水极端的特征与哈德利中心区域模型第3版（HadRM 3）和罗斯比中心区域大气模型第4版（RCA 4）区域气候模型（RCM）模拟的特征，这些模型由再分析驱动，并研究了每小时降水的日周期及其对强度和表面温度的依赖性。所观察到的暖季（5月至9月）最大值的短持续时间（1，2和3小时）的金额显示一个日峰值在下午，这是合理的模拟RCA4，虽然峰值出现过早的模型。HadRM 3提供了一个不切实际的昼夜循环，夜间峰值和下午最小值与所有三个集合成员的观测最大值相吻合，这表明对流没有被真实地捕获。HadRM 3中每小时降水量与日最高温度的日周期的扭曲关系进一步证明，在此RCM中，潜在的物理机制是错误的。拟合优度检验表明，广义极值分布是一个适用的模型观测和RCM模拟的降水最大值。然而，RCMs无法捕获的范围内的形状参数估计的分布短持续降水最大值现实，导致太多（几乎所有的HadRM3）或太少（RCA4）网格框中的形状参数对应于一个沉重的尾巴。这意味着，在RCM模拟的数据中，次日数量的最大值的分布是扭曲的，并且与现实不匹配。因此，在气候变化情景中，基于不解决对流的区域气候模型的次日降水极端事件的预测变化需要谨慎解释。
The study compares characteristics of observed sub-daily precipitation extremes in the Czech Republic with those simulated by Hadley Centre Regional Model version 3 (HadRM3) and Rossby Centre Regional Atmospheric Model version 4 (RCA4) regional climate models (RCMs) driven by reanalyses and examines diurnal cycles of hourly precipitation and their dependence on intensity and surface temperature. The observed warm-season (May–September) maxima of short-duration (1, 2 and 3 h) amounts show one diurnal peak in the afternoon, which is simulated reasonably well by RCA4, although the peak occurs too early in the model. HadRM3 provides an unrealistic diurnal cycle with a nighttime peak and an afternoon minimum coinciding with the observed maximum for all three ensemble members, which suggests that convection is not captured realistically. Distorted relationships of the diurnal cycles of hourly precipitation to daily maximum temperature in HadRM3 further evidence that underlying physical mechanisms are misrepresented in this RCM. Goodness-of-fit tests indicate that generalised extreme value distribution is an applicable model for both observed and RCM-simulated precipitation maxima. However, the RCMs are not able to capture the range of the shape parameter estimates of distributions of short-duration precipitation maxima realistically, leading to either too many (nearly all for HadRM3) or too few (RCA4) grid boxes in which the shape parameter corresponds to a heavy tail. This means that the distributions of maxima of sub-daily amounts are distorted in the RCM-simulated data and do not match reality well. Therefore, projected changes of sub-daily precipitation extremes in climate change scenarios based on RCMs not resolving convection need to be interpreted with caution.
影响因子：
18.3
作者：
Chan, Steven C.;Kendon, Elizabeth J.;Blenkinsop, Stephen
通讯作者：
Blenkinsop, Stephen