Relationships between atmospheric circulation indices and rainfall in Northern Algeria and comparison of observed and RCM-generated rainfall
Relationships between atmospheric circulation indices and rainfall in Northern Algeria and comparison of observed and RCM-generated rainfall
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阿尔及利亚北部大气环流指数与降雨之间的关系以及观测与 RCM 产生的降雨的比较
DOI：
10.1007/s00704-015-1626-4
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发表时间：
2015
影响因子：
3.4
通讯作者：
A. Assani
中科院分区：
文献类型：
--
作者：
Sabrina Taïbi;M. Meddi;Gil Mahé;A. Assani
这项工作的目的是，作为第一步，在阿尔及利亚北方，特别是极端事件，在1940年至2010年期间的降雨量变化进行分析。对年降雨量的分析表明，自1970年代以来，西北部各站的降雨量大幅减少。每个百分位数（第5、第10、第25、第50、第75、第90、第95和第99）和每个降雨间隔等级（1-5、5-10、10-20、20-50和≥50 mm）的雨天频率在日降雨量演变中没有显示出显著变化。Tenes气象站是唯一一个在10-20 mm间隔等级的第75个百分位数以下的雨天频率出现显著下降的气象站。第90百分位数、第95百分位数和第99百分位数的极端事件时间演变没有显着变化。厄尔尼诺-南方涛动和地中海涛动对降水变率和大气环流指数年际和极端事件变率之间的关系有一定的影响。南方涛动指数和研究区西北部的年降雨量之间存在显著的相关性，这可能与该地区降雨量的减少有关。阿尔及利亚北方的季节性降雨受西部的地中海涛动和北大西洋涛动的影响。利用偏差法对ENSEMBLES区域气候模式（RCMs）进行了评估，以检验其在不同时间尺度上再现降水变率的能力。国家气象研究中心（CNRM）、捷克水文气象研究所（CHMI）、苏黎世Eidgenössische Technische Hochschule（ETHZ）和Forschungszentrum盖斯塔赫特（GKSS）模型得出的结果偏差最小。
This work aims, as a first step, to analyze rainfall variability in Northern Algeria, in particular extreme events, during the period from 1940 to 2010. Analysis of annual rainfall shows that stations in the northwest record a significant decrease in rainfall since the 1970s. Frequencies of rainy days for each percentile (5th, 10th, 25th, 50th, 75th, 90th, 95th, and 99th) and each rainfall interval class (1–5, 5–10, 10–20, 20–50, and ≥50 mm) do not show a significant change in the evolution of daily rainfall. The Tenes station is the only one to show a significant decrease in the frequency of rainy days up to the 75th percentile and for the 10–20-mm interval class. There is no significant change in the temporal evolution of extreme events in the 90th, 95th, and 99th percentiles. The relationships between rainfall variability and general atmospheric circulation indices for interannual and extreme event variability are moderately influenced by the El Niño-Southern Oscillation and Mediterranean Oscillation. Significant correlations are observed between the Southern Oscillation Index and annual rainfall in the northwestern part of the study area, which is likely linked with the decrease in rainfall in this region. Seasonal rainfall in Northern Algeria is affected by the Mediterranean Oscillation and North Atlantic Oscillation in the west. The ENSEMBLES regional climate models (RCMs) are assessed using the bias method to test their ability to reproduce rainfall variability at different time scales. The Centre National de Recherches Météorologiques (CNRM), Czech Hydrometeorological Institute (CHMI), Eidgenössische Technische Hochschule Zürich (ETHZ), and Forschungszentrum Geesthacht (GKSS) models yield the least biased results.