SCIENCE@home

The measurement of aerosol optical properties at a rural site in Northern China

P. Yan,J. Tang,Jianqing Huang,J. Mao,X. J. Zhou,Q. Liu,Zifa Wang,H. G. Zhou

Published 2007 in Atmospheric Chemistry and Physics

ABSTRACT

Atmospheric aerosols constitute one of the largest sources of uncertainty in the estimation of radiative forcing for climate. From April 2003 to January 2005, in situ mea- surements of aerosol optical properties were conducted at a rural site in Northern China, Shangdianzi Global Atmo- sphere Watch (GAW) regional station (SDZ), about 150 km from Beijing. Mean values (standard deviation, S.D.) of scat- tering and absorption coefficients for the entire period are 174.6 Mm 1 (189.1 Mm 1 ) and 17.5 Mm 1 (13.4 Mm 1 ), respectively. These values are approximately one third of the reported values for scattering coefficients and one fifth of those for absorption coefficients obtained in the Beijing ur- ban area. The mean single scattering albedo (SSA) for the entire period was estimated as 0.88 (0.05), which is about 0.07 higher than the values reported for the Beijing urban area, and also higher than the values (0.85) used in a re- ported climate simulation for China and India. Both the ab- sorption and scattering coefficients showed a seasonal cycle with the lowest values in winter, while the highest values occurred in summer for absorption coefficients and in fall for scattering coefficients. The mean SSA values were low- est in spring and highest in winter. The daily variations of aerosol absorption and scattering coefficients were strongly influenced by synoptic changes throughout the observation period. A trajectory cluster analysis was applied to dis- cern the source characteristics of aerosol optical properties for different air masses. The cluster-mean aerosol scattering coefficients, absorption coefficients and SSA were all high when the air masses moved from SW and SE-E directions to the site and aerosols were influenced with heavy pollution from the dense population centers and industrial areas. The cluster-mean SSA for air masses coming from the polluted areas was not only higher than those with trajectories from the "clean" directions, but also higher than the reported val- ues for the regions with high pollution emissions (such as the Beijing urban area). This fact might reflect the substantial secondary aerosol production during transport. The charac- teristics of aerosol optical properties measured at this rural site suggest significant impacts of human activities on the re- gional aerosol.

PUBLICATION RECORD

CITATION MAP

EXTRACTION MAP

CLAIMS

  • No claims are published for this paper.

CONCEPTS

  • No concepts are published for this paper.

REFERENCES

Showing 1-44 of 44 references · Page 1 of 1

CITED BY

Showing 1-100 of 155 citing papers · Page 1 of 2

12
Next