A change in urban air quality brought about by varying meteorological parameters

The influence of meteorological parameters on ozone concentrations will become increasingly important as the climate changes. An increase in the frequency of stagnation periods and a decline in the number of frontal passages are expected during the 21st century. This has significant ramifications on ozone concentrations and air quality since frontal passages are a major source of pollution ventilation. General circulation models also predict that an increase in the number of heat waves will lead to an increase in surface temperatures, a decrease in cloud cover, and a subsequent decline in air quality. This study focused on determining what the effect of increasing surface temperatures and stagnation patterns will be on urban air quality in the Oklahoma City Metropolitan area. A statistical analysis was performed on ozone and meteorological data from the Environmental Protection Agency (EPA) and Oklahoma Mesonet, respectively. 2011 and 2012 were exceptionally warm and dry compared to the climatological normal and were therefore used as case study years for determining the impact of hot, dry conditions on air quality. These results were then compared to cooler, wetter summers to show how urban air quality is affected by a change in meteorological parameters. It was found that an increase in summertime heat and a decrease in summertime precipitation will lead to a substantial increase in both the average monthly minimum and maximum ozone concentrations as well as an increase in the total number of exceedance days. During the hotter, drier years, the number of days with ozone concentrations above the legal regulatory limit increased nearly threefold. The length of time in which humans and crops are exposed to these unsafe levels was also doubled. Furthermore, a significant increase was noted in the overnight minimum ozone concentrations. This in turn will lead to significant, adverse affects on both health and agriculture statewide.