Loess record of the aerodynamic environment in the east Asia monsoon area since 60,000 years before present
文献类型:期刊论文
作者 | Qin, XG; Cai, BG; Liu, TS |
刊名 | JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
![]() |
出版日期 | 2005-01-29 |
卷号 | 110期号:B1 |
ISSN号 | 2169-9313 |
DOI | 10.1029/2004JB003131 |
文献子类 | Article |
英文摘要 | [1] The multimodal distribution of grains in loess and dust storm deposits has been widely reported in recent years. Our analysis demonstrates that the interaction of wind, atmospheric turbulence, and dust grain gravity along the dust transportation path results in a multimodal grain size distribution for suspended dust. Changes in the median sizes of the coarse and medium modes are related to variation in aerodynamic forcing ( lift force related to vertical wind and turbulence) during dust entrainment in the source area and turbulence intensity in the depositional area. On the basis of the numeric characteristics of the three modes of suspended particles, a tentative model has been constructed, which is used to study fluctuations of paleoaerodynamic environments. From a time series of paleoatmospheric environmental changes of the loess plateau for the past 60,000 years, we find that there are three patterns of aerodynamic environments in the dust source area ( stronger, strong, weak) and 13 strong turbulence events since 60,000 years B. P. Climatic variability in the dust depositional area is stronger than in the source area. During the last glacial period the aerodynamic environment changed synchronously in the dust source and depositional areas over the entire trend. However, after 8000 years B. P. the aerodynamic force is strong in the dust source area, while the turbulence intensity is weak in the dust depositional area, differing from that of the last glacial period. The strong turbulence periods correspond to the cooling events such as the Heinrich events and the Younger Dryas cold event and may not be related to factors forcing the alternation between glacial and interglacial periods. Since 60,000 years B. P. the three patterns of aerodynamic environments are mainly controlled by the environmental changes in the dust source area and may be related to fluctuations of the winter monsoon. In each pattern, fluctuations of the turbulence intensity in the dust depositional area and the distance from dust source to dust depositional area are the major changes of the environment. The summer monsoon, recorded by magnetic susceptibility, may vary prior to the winter monsoon since 50,000 years B. P. Changes in the intensity of the summer monsoon may force changes in the advance-retreat cycles of dust source areas in each winter monsoon pattern. |
WOS关键词 | AEROSOL-SIZE DISTRIBUTIONS ; WIND EROSION ; MINERAL AEROSOL ; CENTRAL CHINA ; NORTHERN-HEMISPHERE ; GRAIN-SIZE ; CLIMATE ; DUST ; PLATEAU ; MODEL |
WOS研究方向 | Geochemistry & Geophysics |
语种 | 英语 |
WOS记录号 | WOS:000226686800001 |
出版者 | AMER GEOPHYSICAL UNION |
源URL | [http://ir.iggcas.ac.cn/handle/132A11/65740] ![]() |
专题 | 中国科学院地质与地球物理研究所 |
通讯作者 | Qin, XG |
作者单位 | Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China |
推荐引用方式 GB/T 7714 | Qin, XG,Cai, BG,Liu, TS. Loess record of the aerodynamic environment in the east Asia monsoon area since 60,000 years before present[J]. JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,2005,110(B1). |
APA | Qin, XG,Cai, BG,&Liu, TS.(2005).Loess record of the aerodynamic environment in the east Asia monsoon area since 60,000 years before present.JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,110(B1). |
MLA | Qin, XG,et al."Loess record of the aerodynamic environment in the east Asia monsoon area since 60,000 years before present".JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH 110.B1(2005). |
入库方式: OAI收割
来源:地质与地球物理研究所
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。