Modelling extreme dry spells in the Mediterranean region in connection with atmospheric circulation
Modelling extreme dry spells in the Mediterranean region in connection with atmospheric circulation
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模拟地中海地区与大气环流相关的极端干旱
DOI：
10.1016/j.atmosres.2017.11.015
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发表时间：
2018
影响因子：
5.5
通讯作者：
Hertig
中科院分区：
文献类型：
--
作者：
Tramblay;Hertig
长期干旱会在冬季影响地中海地区，因为冬季是年降水量最多的季节，因此对农业、地下水位和水资源产生严重影响。本研究的目标是模拟在冬季（10月至4月）发生的年度最大干旱期长度（AMDSL）。首次研究了极端干旱期的空间格局及其与大尺度大气环流的关系。然后，AMDSL建模使用广义极值（GEV）分布纳入气候协变量，极端干旱的天气模式的依赖性，使用模拟方法进行评估。1960年至2009年期间，每天降水测量的160个雨量计的网络的数据被认为是与20世纪世纪的ERA-20 C再分析，以提供大气变量（位势高度，湿度，风）。AMDSL的发生和持续时间的区域分类有助于区分三个空间上连续的区域，其中发现区域分布均匀。综合分析发现，高度场（Z500）、纬向风场（U850）、相对湿度和比湿度（S850、R850）的显著正距平、负距平与AMDSL在3个区域的分布有显著的相关性，为模拟日的建立提供了参考。最后，比较了位置和尺度参数与不同大气指数相关的非平稳GEV模式。结果表明，在整个地中海尺度上，北大西洋涛动指数的正异常和地中海涛动指数在较小程度上与大多数站点的极端干旱时间较长有关。对于确定的三个地区，在北非的U850负异常的频率显着相关的AMDSL的大小。AMDL也与东南部地区S850负异常的频率有关，与地中海西部和东北部地区Z500正异常有关。
Long droughts periods can affect the Mediterranean region during the winter season, when most of annual precipitation occurs, and consequently have strong impacts on agriculture, groundwater levels and water resources. The goal of this study is to model annual maximum dry spells lengths (AMDSL) that occur during the extended winter season (October to April). The spatial patterns of extreme dry spells and their relationships with large-scale atmospheric circulation were first investigated. Then, AMDSL were modelled using Generalized Extreme Value (GEV) distributions incorporating climatic covariates, to evaluate the dependences of extreme dry spells to synoptic patterns using an analogue approach. The data from a network of 160 rain gauges having daily precipitation measurements between 1960 and 2009 are considered together with the ERA-20C reanalysis of the 20th century to provide atmospheric variables (geopotential heights, humidity, winds). A regional classification of both the occurrence and the duration of AMDSL helped to distinguish three spatially contiguous regions in which the regional distributions were found homogeneous. From composite analysis, significant positive anomalies in geopotential height (Z500) and negative anomalies in zonal wind (U850) and relative and specific humidity (S850, R850) were found to be associated with AMDSL in the three regions and provided the reference to build analogue days. Finally, non-stationary GEV models have been compared, in which the location and scale parameters are related to different atmospheric indices. Results indicates, at the whole Mediterranean scale, that positives anomalies of the North Atlantic Oscillation index and to a lesser extent the Mediterranean Oscillation index are linked to longer extreme dry spells in the majority of stations. For the three regions identified, the frequency of U850 negative anomalies over North Africa is significantly associated with the magnitude of AMDSL. AMDL are also associated with the frequency of S850 negative anomalies for the southeastern region, and with positive Z500 anomalies for the Western and North-eastern Mediterranean regions.
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影响因子：
4.6
作者：
Xoplaki, E;González-Rouco, JF;Wanner, H
通讯作者：
Wanner, H
勘误表：冬季地中海降水对大气环流对气候变化响应的依赖（2015 Environ. Res. Lett. 10 104012）
DOI：
--
发表时间：
2015
期刊：
影响因子：
--
作者：
G. Zappa;B. Hoskins;T. Shepherd
通讯作者：
T. Shepherd
1865年至1984年马赛干旱期的变化
DOI：
--
发表时间：
1987
期刊：
影响因子：
--
作者：
A. Douguédroit
通讯作者：
A. Douguédroit
雨季期间地中海盆地的极端干旱检测和气候学
DOI：
--
发表时间：
2016
期刊：
影响因子：
--
作者：
F. Raymond;A. Ullmann;P. Camberlin;P. Drobinski;Carmela Chateau Smith
通讯作者：
Carmela Chateau Smith
DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
Y. Tramblay;S. E. Adlouni;E. Servat
通讯作者：
E. Servat