气候变化领域集成服务门户(CCPortal): Long-term (1980–2018) spatial and temporal variability of the atmospheric dust load and deposition fluxes along the North-African coast of the Mediterranean Sea

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DOI	10.1016/j.atmosres.2019.104689
	Long-term (1980–2018) spatial and temporal variability of the atmospheric dust load and deposition fluxes along the North-African coast of the Mediterranean Sea
	Bibi M.; Saad M.; Masmoudi M.; Laurent B.; Alfaro S.C.
发表日期	2020
ISSN	0169-8095
卷号	234
英文摘要	The Sahara is a major source of mineral particles for the Mediterranean Sea. The air-suspended particles alter the radiative transfer of solar and terrestrial radiation and the input of nutrients resulting from the deposition of mineral dust into the surface waters is thought to be essential for the development of marine ecosystems. In order to document the spatial and temporal variabilities of the dust atmospheric content and deposition flux close to the North-African coast where the impacts are expected to be the largest but where experimental stations are cruelly lacking, we use the MERRA-2 monthly reanalysis data of the 1980–2018 period. We have extracted the dust optical depth (AODdust), surface concentrations (Cdust), precipitations (Prcp), and deposition fluxes (Fdry, Fwet, and Ftot) of 14 areas (7 coastal and 7 offshore) regularly spaced from the Straights of Gibraltar in the west to Egypt and Cyprus in the east. The principal Component Analysis (PCA) shows that 86% of the variability of AODdust can be explained by two factors only: F1 whose influence is dominant in the Central Mediterranean and peaks in spring, and F2 whose importance decreases from Morocco to Egypt and peaks in summer. The variability of the surface concentration is more complex than that of the optical depth. AODdust and Cdust are maximal downwind of the main Algerian and Libyan dust sources, which is to say on and off the coast of the Central Mediterranean (south-Tunisia, Libya, Malta …). In spite of the climate change already underway, no long-term trend of Cdust or AODdust can yet be evidenced for any of the 14 areas between 1980 and 2018. Along the coast of the eastern basin, the low precipitations (from 6.1 to 10.5 mm month−1 on average) explain that dry deposition accounts for a significant (45–53%) proportion of the total deposition. Everywhere else, wet deposition dominates and particularly in the marine areas where it represents about 90% of the total. From 1980 to 2018, the monthly averaged Ftot did not increase significantly. It varies from 0.24 (eastern Egypt) to 0.63 g m−2 month−1 (south-Tunisia) along the North-African coast, and from 0.26 (Baleares) to 0.48 g m−2 month−1 (Malta) in the marine areas. Because of the spatial variability of the precipitations, the largest deposition fluxes do not necessarily coincide with the regions of largest atmospheric dust content. © 2019
英文关键词	Deposition; Mediterranean; MERRA-2; Mineral dust; Optical depth; Surface concentration
学科领域	Climate change; Deposition; Ecosystems; Infrared radiation; Minerals; Offshore oil well production; Optical properties; Principal component analysis; Mediterranean; MERRA-2; Mineral dust; Optical depth; Surface concentration; Dust; atmospheric deposition; atmospheric pollution; concentration (composition); dust; optical depth; particulate matter; principal component analysis; radiative transfer; spatial variation; temporal variation; Egypt; Mediterranean Sea; Morocco; North Africa
语种	英语
scopus关键词	Climate change; Deposition; Ecosystems; Infrared radiation; Minerals; Offshore oil well production; Optical properties; Principal component analysis; Mediterranean; MERRA-2; Mineral dust; Optical depth; Surface concentration; Dust; atmospheric deposition; atmospheric pollution; concentration (composition); dust; optical depth; particulate matter; principal component analysis; radiative transfer; spatial variation; temporal variation; Egypt; Mediterranean Sea; Morocco; North Africa
来源期刊	Atmospheric Research
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/120539
作者单位	Physics Department, Faculty of Sciences of Sfax, Sfax University, Soukra Road, Sfax, 3038, Tunisia; LISA-UMR CNRS 7583, Universités Paris-Est Créteil et Paris-Diderot, IPSL, Créteil, France
推荐引用方式 GB/T 7714	Bibi M.,Saad M.,Masmoudi M.,等. Long-term (1980–2018) spatial and temporal variability of the atmospheric dust load and deposition fluxes along the North-African coast of the Mediterranean Sea[J],2020,234.
APA	Bibi M.,Saad M.,Masmoudi M.,Laurent B.,&Alfaro S.C..(2020).Long-term (1980–2018) spatial and temporal variability of the atmospheric dust load and deposition fluxes along the North-African coast of the Mediterranean Sea.Atmospheric Research,234.
MLA	Bibi M.,et al."Long-term (1980–2018) spatial and temporal variability of the atmospheric dust load and deposition fluxes along the North-African coast of the Mediterranean Sea".Atmospheric Research 234(2020).