Atmospheric ventilation corridors and coefficients for pollution plume released from an Industrial Facility in Ile-Ife Suburb, Nigeria

Abstract

This study presents a comparative investigation of atmospheric ventilation corridors and coefficients for gaseous pollution plume released from an isolated industrial facility into the ambient air of the host community in Ile-Ife suburb, southwest Nigeria. For the months of September to December in the year 2012 and 2013, measurement of surface layer atmospheric parameters made from an instrumented mast located near the industrial facility were used to parameterize for mixing layer height (MLH). Estimates of ventilation coefficients were obtained as well as in-depth analysis of the ventilation corridors performed. With an estimated carbon monoxide (CO) emission rate of 3.37 gs-1 from the industrial facility, AERMOD regulatory dispersion model was executed within a domain covering 8 km × 6 km around the host community. Effect of monthly changes in local ventilation corridors on pollutants dispersal at the study location was analyzed. Observed speed wind at the study location was weak (monthly mean value is ~ 1.5 m-s-1). The wind direction was predominantly southwesterly, indicating ventilation corridors were towards the northeast of the region. Characteristic values of the atmospheric ventilation coefficients varied from month to month and from daytime (08:00 to 19:00, GMT+1) to nighttime (20:00 to 07:00, GMT+1) with daily maximum values occurring in the late afternoon between (13:00 to 17: 00, GMT+1). The maximum values obtained were 1216 m-1. The study reveals that locations SE and NE of the scrap-iron recycling factory are prevalently exposed to high concentration of gaseous pollutants and the populace in those corridors is potentially susceptible to long-term adverse effects.

To the Question of the Assessment of Ecological Comfort of the Climate

“…Anthropogenically caused impurities in the surface layer and the breeze circulation that is formed in this area have a very favorable effect on the dispersion. In addition to the coefficient of self-purification of the atmosphere, KM, within the framework of this study, the meteorological indicator of atmospheric pollution, MPA, developed in was also calculated and evaluated, the values of which recently also steadily show the predominance of dispersion conditions over the accumulation of impurities in the surface layer of the atmosphere [3][4][5][6][7] .…”

Analyzing and Predicting Ventilation Coefficient over India using Long-term Reanalysis Datasets and Hybrid Machine Learning Approach

“…The anthropogenic emissions of various aerosols are increasing day by day over India due to mass movement of people from rural to urban areas, degrading the AQ in urban areas (e.g. Abiye et al, 2016). Therefore, it is important to study the diurnal pattern of VC to understand the air quality patterns throughout the day.…”

“…Studying the VC to identify ventilation corridors (regions with low pollution potential) and suitable locations for new industries is important. It also helps to assess the damage caused by existing industries and determine the locations that are most vulnerable to the pollution plume (Abiye et al, 2016). The VC varies across India, depending on atmospheric and land surface conditions.…”

“…A higher VC indicates good AQ with high dispersive capacity, while a lower VC indicates poor ventilation (or AQ). Several studies have discussed the variation of VC across the Indian sub-continent (Kannemadugu et al, 2021;Kumar, 2019;Saha et al, 2019;Karuna et al, 2017;Sujatha et al, 2016) as well as global scale (Abiye et al, 2016;Chan et al, 2012;Holzworth, 1967). For example, Holzworth (1967) reported that Los Angeles had low VC (poor air quality) among the seven locations studied in the United States.…”