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Regional characteristics of dust events in China

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Journal of Geographical Sciences 2003年第1期13卷 35-44页

作者： WANGShigong WANGJinyan ZHOUZijiang SHANGKezheng YANGDebao ZHAO 93864Army75UnitXinjiang Changji831112China DepartmentofAtmosphericscience CollegeofResources＆EnvironmntLanzhouUniversityLanzhou730000China NationalMeteorologicalCenter Beijing100081China

The regional characteristics of dust events in China has b een mainly studied by using the data of dust storm, wind-blown sand and floating dust from 338 observation stations through China from 1954 to 2000. The results of this study are as follows: (1) In China, there are two h igh frequent areas of dust events, one is located in the area of Min feng and Hotan in the South Xinjiang Basin, the other is situated in the area of Minqin and Jilantai in the Hexi Region. Furthermore, th e spatial distributions of the various types of dust events are diffe rent. The dust storms mainly occur in the arid and semiarid areas co vering the deserts and the areas undergoing desertification in northern China. Wind-blown sand and floating-dust not only occur in the areas where dust storms occur, but also extend to the neighboring areas. The range of wind-blown sand extends northeastward and southeastward, b ut floating-dust mainly extends southeastward to the low-latitude region such as the East China Plain and the area of the middle and lower reaches o f the Yangtze River. Compared with wind-blown sand, the floating-dust seldo m occurs in the high latitude areas such as North Xinjiang and North east China. (2) The affected areas of dust storms can be divided into seven sub-regions, that is, North Xinjiang Region, South Xinjiang Reg ion, Hexi Region, Qaidam Basin Region, Hetao Region, Northeastern China Region and Qinghai-Xizang (Tibet) Region. The area of the most freque nt occurrence of dust storms and floating-dust is in South Xinjiang Region, and of wind-blown sand in the Hexi Region. In general, the frequency of d ust events in all the seven regions shows a decreasing tendency from 19 54 to 2000, but there are certain differences between various dust events in d ifferent regions. The maximum interannual change and variance of dust events during this time happened in South Xinjiang Region and Hexi Re gion. The dust events generally occur most frequently in April in most pa rts

关键词： dust events regional characteristics

Modifications in aerosol physical, optical and radiative properties during heavy aerosol events over Dushanbe, Central Asia

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Geoscience Frontiers 2021年第6期12卷 299-312页

作者： Dipesh Rupakheti Maheswar Rupakheti Xiufeng Yin Julian Hofer Mukesh Rai Yuling Hu Sabur F.Abdullaev Shichang Kang State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Institute for Advanced Sustainability Studies PotsdamGermany Leibniz Institute for Tropospheric Research LeipzigGermany Physical Technical Institute of the Academy of Sciences of Tajikistan DushanbeTajikistan Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China

The location of Central Asia,almost at the center of the global dust belt region,makes it susceptible for dust *** studies on atmospheric impact of dust over the region are very limited despite the large area occupied by the region and its proximity to the mountain regions (Tianshan,Hindu Kush-KarakoramHimalayas,and Tibetan Plateau).In this study,we analyse and explain the modification in aerosols’physical,optical and radiative properties during various levels of aerosol loading observed over Central Asia utilizing the data collected during 2010–2018 at the AERONET station in Dushanbe,*** episodes were classified as strong anthropogenic,strong dust and extreme *** mean aerosol optical depth (AOD) during these three types of events was observed a factor of ~3,3.5 and 6.6,respectively,higher than the mean AOD for the period 2010–*** corresponding mean fine-mode fraction was 0.94,0.20 and 0.16,respectively,clearly indicating the dominance of fine-mode anthropogenic aerosol during the first type of events,whereas coarse-mode dust aerosol dominated during the other two types of *** was corroborated by the relationships among various aerosol parameters (AOD ***,and EAE ***,SSA and RRI).The mean aerosol radiative forcing (ARF) at the top of the atmosphere (ARF_(TOA)),the bottom of the atmosphere (ARF_(BOA)),and in the atmosphere (ARFATM) were -35±7,-73±16,and38±17 Wm^(-2)during strong anthropogenic events,-48±12,-85±24,and 37±15 Wm^(-2)during strong dust event,and -68±19,-117±38,and 49±21 Wm-2during extreme dust *** in aerosol loading enhanced the aerosol-induced atmospheric heating rate to 0.5–1.6 K day^(-1)(strong anthropogenic events),0.4–1.9 K day^(-1)(strong dust events) and 0.8–2.7 K day^(-1)(extreme dust events).The source regions of air masses to Dushanbe during the onset of such events are also *** study contributes to the understanding of dust and anthropogenic aerosols,in particular the extreme

关键词： dust events Aerosol optical properties AERONET Dushanbe Central Asia

Spatial trends of dustfall over northern China in the spring and their influencing factors

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Research in Cold and Arid Regions 2010年第6期2卷 529-537页

作者： JinChang Li ZhiBao Dong GuangQiang Qian WanYin Luo Institute of Loess Plateau Shanxi UniversityTaiyuanShanxi 030006China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of ScienceLanzhouGansu 730000China

The spatial trends of dustfall of different sizes over northern China during April and May 2001,and March 2002,and their influencing factors,were *** divided the dustfall into seven grades based on particle *** dustfall and dustfall for each grade were highest in desert regions then in regions undergoing desertification,and the total dustfall,dustfall dustfall >250 μm were higher in western agricultural regions closer to desert areas than in eastern agricultural *** spatial trends in dustfall dust events,and the content of coarse particles increased with increasing severity of dust *** the spatial trend for dust events appears to be controlled by geomorphic conditions,vegetation coverage,soil moisture,and the distance from dust source,dustfall dust events,but the control decreases with increasing particle ***,the driving force for dust emissions,also influenced the spatial trends in dustfall dustfall 50 to 100 μm in *** dustfall dustfall,the weaker the correlation with wind speed;however,transport of larger particles still occurs,and further research will be required to test the possibility that this dust is entrained mainly by the small-scale dust devils that are commonly observed in the study area.

关键词： dustfall desertification spatial trends dust events geomorphic conditions Northern China