Seasonal variability of modern dust over the Loess Plateau of China

doi:10.1029/2003JD003382

IEECAS OpenIR > 黄土与第四纪地质国家重点实验室（1985-2004）

	Seasonal variability of modern dust over the Loess Plateau of China
	Sun, DH; Chen, FH; Bloemendal, J; Su, RX
	2003-11-06
发表期刊	JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
卷号	108 期号:D21
文章类型	Article
摘要	Atmospheric dust samples were collected at monthly or seasonal time intervals at six sites on the Chinese Loess Plateau during 1995-1996 and 2000. The dusts are mainly composed of mineral grains in addition to a considerable amount of organic material, especially in the case of the dusts deposited in summer. The magnetic susceptibility of these modern dusts is generally higher than that of glacial loess, and in addition they show clear seasonal variations with maximum values in the summer dust and minimum values in the winter dust. Assuming that pollution effects on modern dust can be excluded, this implies that the high susceptibility values of Quaternary paleosols may arise either from the direct effect of climate on the baseline susceptibility of the raw dust or from further enhancement by post-depositional pedogenesis. The pattern of seasonal dust flux shows that most of the total annual dust deposition is generated by continuous deposition throughout the year rather than by dust storms in specific seasons; however, the flux does exhibit seasonal variability with highest flux occurring in spring or early summer, especially in the northern Loess Plateau. The grain-size distribution of modern dust shows a positive-skewed asymmetrical pattern that is analogous to Quaternary loess. Seasonal variations in dust grain size are characterized by coarsening in spring and summer and by fining in autumn and winter. At a specific site the dust grain-size strongly depends on height above the local ground surface and decreases nonlinearly with increasing height. On the basis of vertical profiles, spatial trends and the seasonal variability of dust flux and grain size, we infer that modern dust, and thus Quaternary loess, is mostly transported at a low level of the atmosphere throughout the year with intensified dust deposition in spring and early summer.
关键词	modern dust Chinese loess
学科领域	Meteorology & Atmospheric Sciences
DOI	10.1029/2003JD003382
关键词[WOS]	GRAIN-SIZE DISTRIBUTION ; MAGNETIC-SUSCEPTIBILITY ; SEDIMENTS ; MAGNETOSTRATIGRAPHY ; HISTORY ; ORIGIN
收录类别	SCI ; SCIE
语种	英语
WOS研究方向	Meteorology & Atmospheric Sciences
WOS记录号	WOS:000186508200002
出版者	AMER GEOPHYSICAL UNION
引用统计	被引频次：57[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.ieecas.cn/handle/361006/11953
专题	黄土与第四纪地质国家重点实验室（1985-2004）
推荐引用方式 GB/T 7714	Sun, DH,Chen, FH,Bloemendal, J,et al. Seasonal variability of modern dust over the Loess Plateau of China[J]. JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES,2003,108(D21).
APA	Sun, DH,Chen, FH,Bloemendal, J,&Su, RX.(2003).Seasonal variability of modern dust over the Loess Plateau of China.JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES,108(D21).
MLA	Sun, DH,et al."Seasonal variability of modern dust over the Loess Plateau of China".JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES 108.D21(2003).