Associations between ozone and morbidity using the Spatial Synoptic Classification system

Abstract

BackgroundSynoptic circulation patterns (large-scale tropospheric motion systems) affect air pollution and, potentially, air-pollution-morbidity associations. We evaluated the effect of synoptic circulation patterns (air masses) on the association between ozone and hospital admissions for asthma and myocardial infarction (MI) among adults in North Carolina.MethodsDaily surface meteorology data (including precipitation, wind speed, and dew point) for five selected cities in North Carolina were obtained from the U.S. EPA Air Quality System (AQS), which were in turn based on data from the National Climatic Data Center of the National Oceanic and Atmospheric Administration. We used the Spatial Synoptic Classification system to classify each day of the 9-year period from 1996 through 2004 into one of seven different air mass types: dry polar, dry moderate, dry tropical, moist polar, moist moderate, moist tropical, or transitional. Daily 24-hour maximum 1-hour ambient concentrations of ozone were obtained from the AQS. Asthma and MI hospital admissions data for the 9-year period were obtained from the North Carolina Department of Health and Human Services. Generalized linear models were used to assess the association of the hospitalizations with ozone concentrations and specific air mass types, using pollutant lags of 0 to 5 days. We examined the effect across cities on days with the same air mass type. In all models we adjusted for dew point and day-of-the-week effects related to hospital admissions.ResultsOzone was associated with asthma under dry tropical (1- to 5-day lags), transitional (3- and 4-day lags), and extreme moist tropical (0-day lag) air masses. Ozone was associated with MI only under the extreme moist tropical (5-day lag) air masses.ConclusionsElevated ozone levels are associated with dry tropical, dry moderate, and moist tropical air masses, with the highest ozone levels being associated with the dry tropical air mass. Certain synoptic circulation patterns/air masses in conjunction with ambient ozone levels were associated with increased asthma and MI hospitalizations.

Influence of Meteorological Parameters and Air Pollutants onto the Morbidity due to Respiratory Diseases in Castilla-La Mancha, Spain

“…Taking into account these limitations, we argue that the results obtained are congruent with the conclusions of the study by Hanna et al (2011). Bucholz et al (2010) found that the air quality, related with ozone and PM 10 concentrations, was better in cyclonic situations than in anticyclonic ones.…”

“…The objective weather type classification by Lamb (1972) has been used, which has also recently been applied to rainfall patterns in the Iberian Peninsula (Fernandez-Gonzalez et al, 2012). Other authors like Hanna et al (2011) have found that certain synoptic air masses (dry tropical, transitional and extreme moist tropical) in conjunction with ambient ozone air levels were associated with increased asthma hospitalizations. In our study, it was very useful to reduce the total number of situations to a smaller, more manageable number for each period in order to achieve plausible conclusions.…”

“…As for air pollutants, hospital admissions due to asthma may increase in periods with low air quality, in particular when there are increases in ozone rates (Gouveia and Fletcher, 2000a, b;Tolbert et al, 2000;Fusco et al, 2001;Tortolero et al, 2002;Jalaludin et al, 2004;Ho et al, 2007;Hanna et al, 2011). Links have been found between daily ozone levels and respiratory symptoms (Gent et al, 2003;Rabinovitch et al, 2004;Middleton et al, 2008;Stieb et al, 2009).…”

An Air Mass Based Approach to the Establishment of Spring Season Synoptic Characteristics in the Northeast United States

“…For instance, reference [24] used the SSC to help identify days in which significant snow cover ablation was observed in the Central Appalachians. Reference [25] used the SSC to identify a relationship between particular air mass types and the number of emergency room visits for individuals suffering from asthma or other respiratory illnesses in North Carolina. Reference [26] incorporated the SSC into an investigation of the climatology of the TR air mass type in the winter season.…”

Pollution levels and the effect of air pollution on asthma hospitalisations modified by synoptic weather type and aeroallergens

“…To account for this, spatial synoptic classification (SSC) can be used to group weather patterns using a suite of meteorological parameters into distinct categories [1]. The SSC is becoming more widely used to investigate associations between pollutant levels and mortality; one study found that ozone in conjunction with dry tropical and moist tropical weather types increased the risk of hospitalisation for asthma and myocardial infarction [2].…”