Two case studies on NARCCAP precipitation extremes
Two case studies on NARCCAP precipitation extremes
复制标题
NARCCAP 极端降水的两个案例研究
DOI：
--
复制
发表时间：
2013
期刊：
影响因子：
--
通讯作者：
L. Mearns
中科院分区：
文献类型：
--
作者：
Grant B. Weller;D. Cooley;S. Sain;M. Bukovsky;L. Mearns
我们引入了新的方法来检验北美区域气候变化评估计划(NARCCAP)中的六个区域气候模式(RCM)对过去在两个不同区域和季节的观测记录中看到的极端降水事件的模拟能力。我们的主要目标是检查极端降水事件在观测值与RCM和驱动再分析产品的输出之间每日对应的强度。为了探索这种对应关系，我们使用了多元极值理论的方法。这些方法要求我们考虑边际行为，我们首先对描述观测和模型输出的日降水尾部行为的气候量进行建模和比较，然后将注意力转向量化极端事件的对应关系。用两个季节对北美西海岸地区的日降水量进行了分析，发现由再分析驱动的NARCCAP模式模拟的极端事件与观测记录中的极端事件具有很强的日对应关系。我们研究了美国中部地区的降水，发现再分析驱动的NARCCAP模式模拟的冬季极端与观测中看到的冬季极端之间存在一定的日对应关系，而夏季极端则没有这种对应关系。此外，我们发现NARCCAP模式在该地区夏季日降水分布的尾部特征上比西海岸地区的降水有更大的差异。我们发现，使用光谱轻推的模式对中心区域的观测结果表现出更强的尾部相关性。
We introduce novel methodology to examine the ability of six regional climate models (RCMs) in the North American Regional Climate Change Assessment Program (NARCCAP) ensemble to simulate past extreme precipitation events seen in the observational record over two different regions and seasons. Our primary objective is to examine the strength of daily correspondence of extreme precipitation events between observations and the output of both the RCMs and the driving reanalysis product. To explore this correspondence, we employ methods from multivariate extreme value theory. These methods require that we account for marginal behavior, and we first model and compare climatological quantities which describe tail behavior of daily precipitation for both the observations and model output before turning attention to quantifying the correspondence of the extreme events. Daily precipitation in a West Coast region of North America is analyzed in two seasons, and it is found that the simulated extreme events from the reanalysis‐driven NARCCAP models exhibit strong daily correspondence to extreme events in the observational record. Precipitation over a central region of the United States is examined, and we find some daily correspondence between winter extremes simulated by reanalysis‐driven NARCCAP models and those seen in observations, but no such correspondence is found for summer extremes. Furthermore, we find greater discrepancies among the NARCCAP models in the tail characteristics of the distribution of daily summer precipitation over this region than seen in precipitation over the West Coast region. We find that the models which employ spectral nudging exhibit stronger tail dependence to observations in the central region.
影响因子：
4.9
作者：
Sillmann, Jana;Croci-Maspoli, Mischa;Katz, Richard W.
通讯作者：
Katz, Richard W.