September 19, 2007
Clouds and Homogenous Boundary Layer
Cloudy skies prevailed throughout the first half of today's observations (dark red counts). A homogeneous boundary layer can be observed up to 0.9 km. Hourly PM 2.5 concentrations in the range of 7.5 to 13.5 ug/m3 [AQI Levels: 24-44 (Good)] were recorded at Maryland's Department of the Enviroment Oldtown site in Baltimore during ELF's operation.