A Time Series Forecasting of Air Pollution in Indore
Forecasting involves the generation of a number, set of numbers, or scenario that corresponds to a future occurrence. It is absolutely essential to short-range and long-range planning. By definition, a forecast is based on past data, as opposed to a prediction, which is more subjective and based on instinct, get feel, or guess. For example, the evening news gives the weather 'forecast' not the weather 'prediction.' Regardless, the terms forecast and predictions are often used inter-changeably. For example, a definition of regression technique sometimes used in forecasting the general statements regarding its purpose is to explain or “predict” the major air pollutants concentration.
Keywords: air quality, discrete time series forecasting, forecasting combination models (FCM), grey model (GM), pollutants concentration
Cities are growing rapidly in size and diversity with increasing emission from vehicular traffic, industry, and refuse burning all poses potential risk for large air pollution exposure. The air pollution problems in large Asian cities including Bangkok, Beijing, Mumbai, Calcutta, Delhi, Jakarta, Karachi, Manila, Seoul, and Shanghai have been reported in 20 mega-city reports (WHO, 1992). India has twenty-three cities of over one million people and ambient air pollution levels exceeded WHO health standards in many of them. Urban air pollution is worsening due to upward trends in power consumption, industrialisation, and vehicle use. As per a World Bank study (Buckland, 1999, World Bank, 1997) ambient air pollution levels (SPM, SO2, Lead and NO2) exceeding WHO standards in thirty-six major Indian cities and towns account for 40,350 premature deaths, around 1,98,05000 thousand hospital admissions and sickness requiring medical treatment and also 1201 million incidences of minor sickness annually.
Six of the ten largest cities in India viz. Mumbai, Kolkata, Delhi, Ahmedabad, Kanpur, and Indore also come under the category of toxic air pollution problems (Gupta, 2002). In addition, Urban Air Quality Management Strategy (URBAIR, 1997) in Asia has studied air pollution status in Katmandu Valley, Jakarta, Metro Manila, and Greater Mumbai. The profile of pollution indicates that these cities have serious to moderate problems due to the high levels of suspended particulate matter (SPM), SO2, and NOX. Ostro (1999) also studied the link of mortality to SPM and respiratory illness from lead, SO2 and other pollutants in United States. Status of air pollution levels and various strategic approaches for air management have been reported (Gajghate, 1999).