The histograms above show the maximum 8-hour surface ozone average, 24-hour PM2.5 average, and temperature in Maryland.  The horizontal lines on the ozone and PM2.5 charts correspond to the National Amibient Air Quality Standard (NAAQS). The horizontal line on the temperature chart corresponds to 90 F.  Often, ozone and PM2.5 are correlated with high temperature as should be visually apparent from the time series (if viewing during the “ozone season”, which runs from April to October). When surface ozone or PM2.5 rises above the horizontal line, Maryland has experienced an ozone or PM2.5 exceedance day.

The surface pressure map is shown because bad air quality is often associated with regional weather patterns such as the Bermuda High, a stationary high pressure system off the U.S. East coast that leads to build up of pollutants in the Mid-Atlantic Region.

Maintained by The Department of Atmospheric and Oceanic Science

College Park, MD 20742-2425 • 301-405-5391 • Fax 301-314-9482

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Created By Daniel Silversmith

Surface Pressure Analysis

30 Day History

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