Trends and variability in extreme precipitation indices over Maghreb countries
Trends and variability in extreme precipitation indices over Maghreb countries
复制标题
马格里布国家极端降水指数的趋势和变化
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
E. Servat
中科院分区：
文献类型：
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作者：
Y. Tramblay;S. E. Adlouni;E. Servat
抽象的。马格里布国家极易受到极端水文事件的影响，如降雨量变化剧烈造成的洪水和干旱。虽然有几项研究分析了欧洲-地中海盆地降水记录中存在的趋势，但这项研究对其最南端海岸的趋势进行了区域评估。位于阿尔及利亚，摩洛哥和突尼斯之间的33和59年的日降水量记录的22个站的数据库被认为是。分析了11个气候指数的变化点和趋势，描述了降水状况的几个特征。进行多个假设检验的问题是通过实施一个错误的发现率程序来解决的。分析了不同站点降水指数的空间和年际变化，并与大尺度大气环流型（包括北大西洋涛动（NAO）、西地中海涛动（WEMO）、地中海涛动（MO）和厄尔尼诺-南方涛动（ENSO））进行了比较。结果表明，降水总量和潮湿的日子一起增加的干燥期的持续时间减少的强烈趋势，主要是摩洛哥和阿尔及利亚西部。另一方面，只有少数显着的趋势检测到强降水指数。NAO和MO模式与描述降水量、干旱天数和干湿期长度的降水指数有很好的相关性，而强降水指数则表现出较强的空间变异性，与大尺度大气环流模式只有中等程度的相关性。
Abstract. Maghreb countries are highly vulnerable to extreme hydrological events, such as floods and droughts, driven by the strong variability of precipitation. While several studies have analyzed the presence of trends in precipitation records for the Euro-Mediterranean basin, this study provides a regional assessment of trends on its southernmost shores. A database of 22 stations located in Algeria, Morocco and Tunisia with between 33 and 59 yr of daily precipitation records is considered. The change points and trends are analyzed for eleven climate indices, describing several features of the precipitation regime. The issue of conducting multiple hypothesis tests is addressed through the implementation of a false discovery rate procedure. The spatial and interannual variability of the precipitation indices at the different stations are analyzed and compared with large-scale atmospheric circulation patterns, including the North Atlantic Oscillation (NAO), western Mediterranean Oscillation (WEMO), Mediterranean Oscillation (MO) and El Nino–Southern Oscillation (ENSO). Results show a strong tendency towards a decrease of precipitation totals and wet days together with an increase in the duration of dry periods, mainly for Morocco and western Algeria. On the other hand, only a few significant trends are detected for heavy precipitation indices. The NAO and MO patterns are well correlated with precipitation indices describing precipitation amounts, the number of dry days and the length of wet and dry periods, whereas heavy precipitation indices exhibit a strong spatial variability and are only moderately correlated with large-scale atmospheric circulation patterns.