干旱区生态环境知识资源中心(Arid): Assessment of mean precipitation and precipitation extremes in Iran as simulated by dynamically downscaled RegCM4

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DOI	10.1016/j.dynatmoce.2024.101452
	Assessment of mean precipitation and precipitation extremes in Iran as simulated by dynamically downscaled RegCM4
	Zarrin, Azar; Dadashi-Roudbari, Abbasali
通讯作者	Zarrin, A
来源期刊	DYNAMICS OF ATMOSPHERES AND OCEANS
ISSN	0377-0265
EISSN	1872-6879
出版年	2024
卷号	106
英文摘要	This paper aims to assess the mean precipitation and precipitation extremes over Iran as simulated by the Regional Climate Model (RegCM4). A simulation spanning 20 years (1991-2010) at a horizontal resolution of 20 Km is driven by the NCEP / NCAR reanalysis. We evaluated the model by comparing simulated precipitation with observations using Bias, Root-Mean-Square Error, and Index of Agreement metrics. We examined the extreme precipitations based on a set of extreme indices recommended by the Expert Team on Climate Change Detection and Indices (ETCCDI) in three categories of intensity (Rx1day and SDII), duration (CDD and CWD), and frequency (R10mm and R20mm). The linear trends are calculated using the Theil-Sen estimator method, and the statistical significance (95% confidence level) is determined by using a modified MannKendall (MMK) trend test. The RegCM4 model satisfactory captured the spatial distribution of precipitation and precipitation extremes, although high bias remained in small parts of Iran, including the northwest and southeast. The northwest bias is due to spring convectional precipitation and the southeast bias could be caused by precipitation from the Asian summer monsoon system, which both of them may not be well simulated by the applied Grell convective scheme. Results indicate that the model reasonably captures Rx1day, SDII, CWD, R10mm, and R20mm Indices over Iran. In good agreement with precipitation observations, the southern coast of the Caspian Sea represents the second-highest extreme precipitation, except for SDII, which is probably due to the high frequency of rainy days in this region. The highest CDD of more than 200 days is found in the arid and semi-arid regions of the southeast. In general, precipitation decreased in most regions of Iran, especially the western, southern, and interior regions. In addition, the results reveal that heavy (R10mm) and very heavy (R20mm) precipitation events have also decreased in the same regions. Results also emphasize an increase in consecutive dry days (CDD) in most parts, especially in the southeast, which deserves more attention in future research. The decreasing trend of precipitation and the increasing trend of CDD show that Iran has become drier in the 2000 s compared to the 1990 s
英文关键词	Precipitation extremes RegCM4 Grell convective scheme Iran
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:001203166600001
WOS关键词	CLIMATE-CHANGE ; UNITED-STATES ; TRENDS ; MODEL ; TEMPERATURE ; VARIABILITY ; INDEXES ; REGIMES ; LAND ; ASIA
WOS类目	Geochemistry & Geophysics ; Meteorology & Atmospheric Sciences ; Oceanography
WOS研究方向	Geochemistry & Geophysics ; Meteorology & Atmospheric Sciences ; Oceanography
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/403308
推荐引用方式 GB/T 7714	Zarrin, Azar,Dadashi-Roudbari, Abbasali. Assessment of mean precipitation and precipitation extremes in Iran as simulated by dynamically downscaled RegCM4[J],2024,106.
APA	Zarrin, Azar,&Dadashi-Roudbari, Abbasali.(2024).Assessment of mean precipitation and precipitation extremes in Iran as simulated by dynamically downscaled RegCM4.DYNAMICS OF ATMOSPHERES AND OCEANS,106.
MLA	Zarrin, Azar,et al."Assessment of mean precipitation and precipitation extremes in Iran as simulated by dynamically downscaled RegCM4".DYNAMICS OF ATMOSPHERES AND OCEANS 106(2024).