Vertical distribution characteristics of PM in the surface layer of Guangzhou--颗粒学报PARTICUOLOGY

Deng, X., Li, F., Li, Y., Li, J., Huang, H., & Liu, X. (2015). Vertical distribution characteristics of PM in the surface layer of Guangzhou. Particuology, 20, 3–9. https://doi.org/10.1016/j.partic.2014.02.009

Vertical distribution characteristics of PM in the surface layer of Guangzhou

Xuejiao Deng ^a *, Fei Li ^a, Yuanhong Li ^b, Jianyong Li ^b, Hongzhi Huang ^b, Xiantong Liu ^a

a Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction, China Meteorological Administration (CMA), Guangzhou 510080, China
b Guangdong Atmosphere Sounds Technology Centre, Guangzhou 510080, China

10.1016/j.partic.2014.02.009

Volume 20, June 2015, Pages 3-9

Received 4 September 2013, Revised 28 November 2013, Accepted 28 February 2014, Available online 24 May 2014.

E-mail: dxj@grmc.gov.cn; pkdxj@163.com

Highlights

• The over-standard situation of PM in surface layer of Guangzhou was analyzed.

• Vertical variations of mass concentrations of PM₁₀, PM_2.5 and PM₁ in Guangzhou were investigated.

• Changes in the ratios of PM_2.5/PM₁₀ and PM₁/PM_2.5 were studied.

Abstract

Measurements of particulate matter (PM), i.e., PM₁₀, PM_2.5, and PM₁, have been performed on the Canton Tower, a landmark building in Guangzhou, at heights of 121 and 454 m since November 2010, using a GRIMM 180 aerosol particle spectrometer (Germany). Analyses of data from November 2010 to May 2013 showed that the annual average values of PM₁₀, PM_2.5, and PM₁ at the observation height of 121 m above the ground were 44.1, 38.2, and 34.9 μg/m³, respectively, and those at 454 m above the ground were 35.7, 30.4, and 27.5 μg/m³, respectively. By considering the values of the secondary concentration limits given in the Ambient Air Quality Standards issued in 2012, it was observed that the annual average values of PM₁₀ at the observation heights of 121 and 454 m, as well as those of PM_2.5 at 454 m, reached those standards. Furthermore, the over-standard amplitude of the annual average value of PM_2.5 at the observation height of 121 m was 9.1%. During the observation period, the maximum daily average values of PM₁₀, PM_2.5, and PM₁ at the observation height of 121 m were 183.3, 144.8, and 123.8 μg/m³, respectively, and those at 454 m were 102.8, 92.7, and 86.4 μg/m³. The daily average values of PM₁₀ at the observation height of 454 m were not above the standards. The over-standard frequencies of the daily average values of PM₁₀ and PM_2.5 at the observation height of 121 m were 0.6% and 10.7%, respectively, and the over-standard amplitudes were 9.0% and 24.4%, respectively. The over-standard frequency of the daily average value of PM_2.5 at the observation height of 454 m was 2.0%, and the over-standard amplitude was 10.4%. Accordingly, it can be stated that the air at the observation height 454 m above the ground did not reach the secondary limit of the new standards. The pollution was most serious during winter, and the air was relatively cleaner during summer. Overall, the vertical distributions of PM₁₀, PM_2.5, and PM₁ decreased with height. The lapse rates showed the following sequence: PM₁₀ > PM_2.5 > PM₁, which indicates that the vertical distribution of fine particles is more uniform than that of coarse particles; the vertical distribution in summer is more uniform than in other seasons.

Graphical abstract

Keywords

PM₁₀; PM_2.5; PM₁; Over-standard; Vertical distribution; Surface layer

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