Utilizing map pattern classification and surface weather typing to relate climate to the Air Quality Index in Cleveland, Ohio

Employing both map pattern classification and weather typing, this study examines the role of climate in impacting air quality in Cleveland, Ohio from 1998 to 2007. This research creates a large-scale map pattern-classification of 500 mb geopotential heights that characterizes the broad scale flow of the atmosphere and the Spatial Synoptic Classification (SSC), which typifies the weather situation at the surface, where pollutants ultimately interact with the population. Surface weather types are found to have a greater impact on the Air Quality Index (AQI) than typical circulation patterns. Warm (cool) weather types and circulation patterns with a ridge (trough) consistently relate to poor (better) air quality in Cleveland. When weather types and circulation patterns are considered in tandem, these relationships are reinforced. Circulation patterns appear to have considerable influence on air quality in conjunction with moderate surface weather types, with impacts differing by the primary pollutant considered. Spike days of high AQIs (days with an AQI of at least 100) show similar results.

► We analyze air quality using two synoptic climatological methods in tandem.
► Warm weather types and ridge patters are associated with high AQIs.
► Cold weather types and trough patterns are associated with low AQIs.
► When types and patterns are examined in tandem, both effects are amplified.
► Weather type and circulation pattern impacts differ by season and pollutant.