Status and prediction of carbon monoxide as an air pollutant in Ahvaz City, Iran

In the present study, air quality analyses were conducted for carbon monoxide (CO) in Ahvaz, a city in the south of Iran. The measurements were taken from 2009 through 2010 in two different locations to prepare average data in the city. The average concentrations calculated for every 24 hours, each month and each season showed that the highest CO concentration occurs generally in the nighttime, while the least was found at in the midday. Monthly CO concentrations showed the highest values in May and June, while the least in January and February. The seasonal concentrations showed the highest amounts in the spring. Then Relations between the air pollutant and some meteorological parameters were calculated statistically using the daily average data. The wind data (velocity, direction), relative humidity, temperature, sunshine periods, dew point and rainfall were considered as independent variables. The level relationships between pollutant concentration and meteorological parameters were expressed by multiple linear and nonlinear regression equations for both annual and seasonal conditions using SPSS software. RMSE test showed that among different prediction models, stepwise model is the best option.