Calendar Event Details
AEROCENTER: Rolando Olivas
Affiliation: Johns Hopkins University
Event Date: Tuesday, October 14, 2014
Location: G133
Time: 11:00 AM
Variability of summer PM2.5 in the Northeastern United States and tracing of potential sources using MERRAero reanalysis.
The variability of ground-level concentrations of fine suspended particulate matter (PM2.5) in the Northeastern United States is examined using station measurements from the US Environmental Protection Agency’s Air Quality System (AQS). The long-term variations as well as the occurrence of short-term high concentration episodes in the region are investigated for the period 1999-2013. This analysis shows that there has been a significant decrease in summer PM2.5 between 1999 and 2013 in the Northeastern U.S. region in terms of summer-mean values, the occurrence of high events, and the magnitude of these high events. The relative role of industrial versus biomass burning emissions is explored using measurements from the Interagency Monitoring of Protected Visual Environments (IMPROVE) network and output from the Modern-Era Retrospective Analysis for Research and Applications Aerosol Reanalysis (MERRAero). The potential sources of PM2.5 are analyzed using MERRAero aerosol optical depth (AOD) for two of the main components of the pollutant: organic carbon and sulfate. The analysis shows that high-PM2.5 events in the Northeastern U.S. are, generally, the result of long range transport of smoke from large boreal wildfires, Midwestern industrial emissions, or a combination of both. There are roughly equal numbers of events due to natural or anthropogenic sources for the 2002 - 2012 period for this region. The events that have an anthropogenic source are characterized by a strengthening high pressure system developing in the Southern U.S. These high-pressure systems advect aerosol pollution from the Midwest and cause stagnation of PM2.5 in the Northeastern U.S.
Posted or updated: Thursday, October 9, 2014
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