Characteristics and Source Apportionment of Black Carbon (BC) in a Suburban Area of Klang Valley, Malaysia

Atmosphere

卷:12

Sairam Dhandapani¹  Md Firoz Khan²  Zamzam T. A. Ramly³  Sarva M. Praveena⁴  Eliani Ezani⁴  Mathew R. Heal⁵ 

[1] Council on Energy, Environment and Water, New Delhi 110067, India;

[2] Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Federal Territory, Malaysia;

[3] Department of Environment, Faculty of Forestry and Environment, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia;

[4] Department of Environmental and Occupational Health, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia (UPM), Serdang 43400, Selangor, Malaysia;

[5] School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh EH9 3FJ, UK;

关键词: black carbon;    carbonaceous aerosol;    human health;    Aethalometer;    fossil fuel;    biomass burning;   

DOI  :  10.3390/atmos12060784

来源: DOAJ

【 摘 要 】

Black carbon (BC) is of concern due to its contribution to poor air quality and its adverse effects human health. We carried out the first real-time monitoring of BC in Malaysia using an AE33 Aethalometer. Measurements were conducted between 1 January and 31 May 2020 in a university area in a suburban location of the Klang Valley. The measurement period coincided with the implementation of a movement control order (MCO) in response to COVID-19. The mean concentration of BC before the MCO was 2.34 µg/m³ which decreased by 38% to 1.45 µg/m³ during the MCO. The BC is dominated by fossil-fuel sources (mean proportion BC_ff = 79%). During the MCO, the BC_ff concentration decreased by more than the BC_bb concentration derived from biomass burning. BC and BC_ff show very strong diurnal cycles, which also show some weekday–weekend differences, with maxima during the night and just before noon, and minima in the afternoon. These patterns indicate strong influences on concentrations from both traffic emissions and boundary layer depth. BC was strongly correlated with NO₂ (R = 0.71), another marker of traffic emission, but less strongly with PM_2.5 (R = 0.52). The BC absorption Ångström exponent (AAE) ranged between 1.1 and 1.6. We observed pronounced diurnal cycles of lower AAE in daytime, corresponding to BC_ff contributions from traffic. Average AAE also showed a pronounced increase during the MCO. Our data provides a new reference for BC in suburban Malaysia for the public and policy-makers, and a baseline for future measurements.

【 授权许可】

Unknown