Effects of aerosol species on atmospheric visibility in Kaohsiung City, Taiwan
- National Sun Yat-Sen University (Taiwan)
Visibility data collected from Kaohsiung City, Taiwan, for the past two decades indicated that the air pollutants have significantly degraded visibility in recent years. During the study period, the seasonal mean visibilities in spring, summer, fall, and winter were only 5.4, 9.1, 8.2, and 3.4 km, respectively. To ascertain how urban aerosols influence the visibility, we conducted concurrent visibility monitoring and aerosol sampling in 1999 to identify the principal causes of visibility impairments in the region. In this study, ambient aerosols were sampled and analyzed for 11 constituents, including water-soluble ions and carbon materials, to investigate the chemical composition of Kaohsiung aerosols. Stepwise regression method was used to correlate the impact of aerosol species on visibility impairments. Both seasonal and diurnal variation patterns were found from the monitoring of visibility. Results showed that light scattering was attributed primarily to aerosols with sizes that range from 0.26 to 0.90 {mu}m, corresponding with the wavelength region of visible light, which accounted for {approximately} 72% of the light scattering coefficient. Sulfate was a dominant component that affected both the light scattering coefficient and the visibility in the region. On average, (NH{sub 4}){sup 2}SO{sub 4}, NH{sub 4}NO{sub 3}, total carbon, and fine particulate matter (PM2.5)-remainder contributed 53%, 17%, 16%, and 14% to total light scattering, respectively. An empirical regression model of visibility based on sulfate, elemental carbon, and humidity was developed, and the comparison indicated that visibility in an urban area could be properly simulated by the equation derived herein. 35 refs., 10 figs., 4 tabs.
- OSTI ID:
- 20638633
- Journal Information:
- Journal of the Air and Waste Management Association, Vol. 55, Issue 7; ISSN 1047-3289
- Country of Publication:
- United States
- Language:
- English
Similar Records
Influence of alkaline suspended particles on the chemical composition of acid deposition in Kaohsiung City, Taiwan
Correlation between meteorological conditions and mutagenicity of airborne particulate samples in a tropical monsoon climate area from Kaohsiung City, Taiwan
Related Subjects
20 FOSSIL-FUELED POWER PLANTS
02 PETROLEUM
AEROSOLS
TAIWAN
VISIBILITY
AIR POLLUTION
AIR POLLUTION MONITORING
CHEMICAL COMPOSITION
SEASONAL VARIATIONS
DAILY VARIATIONS
ACID RAIN
PARTICULATES
AMMONIA
SULFATES
AMMONIUM NITRATES
REGRESSION ANALYSIS
URBAN AREAS
LIGHT SCATTERING
FOSSIL-FUEL POWER PLANTS
CARBON
INDUSTRIAL PLANTS
PETROLEUM REFINERIES
POLLUTION SOURCES
PETROCHEMICAL PLANTS
CEMENTS