Author(s)

S. Pongpiachan, T. Supadit, P. Hirunyatrakul, I. Kittikoon & S. Whangthamrongwit

Abstract

One of the most controversial issues on air pollution field is how to quantitatively identify the emission source of gaseous species in atmospheric environment. Air Compass Software was carefully designed for this special purpose by using C# program. Given that wind direction is measured as an angle (α) relative to true north (0), mean direction was determined by using trigonometric relations to determine the direction of the resultant of individual wind vectors. The emission source strength – wind direction relationship can be represented graphically by plotting R-value of (natural logarithm of partial pressure) vs. against downwind angle (α) during the monitoring period. To apply this relationship, measured atmospheric concentrations must be expressed as partial pressures (P), which can be converted through the use of the ideal gas law with a temperature correction. The aims of this study are to statistically quantify the relationships between emission source strengths and downwind angles of Semi-Volatile Organic Compounds (SVOCs) measured at Whitbourne monitoring stations adjacent to Worcester city, UK from 20/11/2003 to 22/12/2003 (cold-period) and from 5/5/2004 to 26/5/2004 (warm-period). Air

Keywords

semi-volatile organic compounds, wind direction, trigonometric, air compass software, Whitbourne