U.S. Air Quality

Poor Air Quality in Baltimore

Today was another hot day with temperatures going up into the 90's (32°c) with 0.07 inches of rain this morning. The PM2.5 concentrations went up to 81.1 µg/m³ as recorded at Oldtown. One can see above in the backscatter plot the day time boundary layer at 1.2km and a raising nocturnal boundary layer at 0.5-1.5 km. At 3:00 UTC one can see a large aerosol plume rising above the boundary layer to 4km with a denser part showing up at 9 UTC and at an altitude of 3-3.5km. Running a back trajectory using the HYSPLIT model one can see it may have been picked up from the west possibly from Ohio or upper Indiana.

Looking at it again, this feature may be from a local source. With the hot weather we have been having the aerosols may have been rising up to a layer at 3.5-4 km and then were capped. In this view the aerosols may have been from a more local source, and if so what we are seeing is the development of a plume in the middle troposphere.

Posted by Paul Schou at August 8, 2007 2:02 AM