Air pollutant concentrations

About: Air pollutant concentrations is a research topic. Over the lifetime, 1652 publications have been published within this topic receiving 36138 citations.

Time Series Analysis of Air Pollutants for Karabük Province

Abstract: The air is polluted and the atmospheric pollution has becoming a great problem for human beings due to the high rate consumption of energy. Most of the scientists dealing with the air pollution state that the first reason of all environmental problems is the population increase. Depending on population, the high consumption of energy (including heating purposes, electricity production, transportation and industries) agricultural activities, waste disposal and the pressure for destroying forest areas create air pollution problem. The atmosphere is polluted and the concentrations of pollutants have increased tremendously. Karabuk Province is one of the famous provinces of heavy industries. There are 3 air quality measurement stations. In this study, the last 2 years hourly and daily air pollutants (PM10, SO2 , NO, NOx , NO2 , O3 and CO) were studied as a time series by using graphical and statistical approaches. The results were considered seasonally and annually. The meteorological condition is also very effective in atmospheric pollution. Moreover, the industrial production and consumption of energy are also high pressure on Karabuk province. The concentrations in each station are also showing different characteristics during two years’ period. The highest concentrations (such as PM10, SO2 , NO, NOx ) are, as usual, seen in winter season due to industrial usage of energy for production and household consumption of energy for heating. However, for O3 , the highest concentration is observed in summer season, because the atmospheric ozone trend is supposed to show an opposite trend compared with NO due to photochemical reaction with these gases. For CO, the maximum concentration is recorded as 4779 μg/m3 in august in 2015. The analyses of data have shown that, the atmosphere is polluted highly with PM10, SO2 , NO, NOx , NO2 , and CO during winter season. The households are very effective using high coal for heating purposes in Karabuk Province.

Intra–Community Scale Variability of Air Quality in the Center of a Megacity in South Korea: A High-Density Cost-Effective Sensor Network

Abstract: To investigate the spatial and temporal variability of air quality (CO, NO2, O3, and PM2.5) with a high spatial resolution in various adjacent micro-environments, 30 sets of sensor-nodes were deployed within an 800 × 800 m monitoring domain in the center of the largest megacity (Seoul) in South Korea. The sensor network was operated in summer and winter. The daily variation in air pollutant concentrations revealed a similar trend, with discernible concentration differences among monitoring sub-sites and a government-operated air quality monitoring station. These differences in pollutant levels (except PM2.5) among the sub-sites were pronounced in the daytime with high volumes of traffic. The coefficient of divergence and Pearson correlation coefficient showed that spatial and temporal variability was more significant in summer than winter. Ozone displayed the greatest spatial variability, with little temporal variability among the sub-sites and a negative correlation with NO2, implying that ozone concentrations were primarily determined by vehicular NOX emissions due to NO titration effects under the urban canopy. The PM2.5 concentration displayed homogeneous spatial and temporal distributions over the entire monitoring period, implying that PM2.5 monitoring with at least a 1 × 1 km resolution is sufficient to examine the spatial and temporal heterogeneity in urban areas.

Morning peak of air pollutant concentrations in urban areas: effect of time lag between emissions and turbulence

Abstract: Primary air pollutants in urban environments, like CO and PM10, show a distinctive diurnal cycle characterized by periods of maximum concentrations in the morning and in the evening. These peaks occur during the times of the day when high emissions combine with a relatively small dispersive capacity of the atmospheric boundary layer (ABL). Moreover, during the morning and evening hours, both the emission rates and the ABL turbulence are highly transient. Therefore, it is reasonable to expect that the timing and the magnitude of the concentration peaks are controlled by the time evolution of the emission rates, the turbulence intensity, and the relative phase between emissions and turbulence.