Fused Air Quality Surfaces Using Downscaling

Based on statistical modeling research in the development of fused space-time predictive surfaces for air quality, this web page provides access to the most recent daily O₃ and PM_2.5 surfaces. As new and improved statistical models become available, we plan to continually update these surfaces. Currently, a Bayesian space-time downscaler model (see DSMetadataAir for journal references, description, limitations, and uses. Please read this file before downloading the predictive surfaces) is used to "fuse" daily ozone (8-hr max) and fine particulate air (24-hr average) monitoring data from the National Air Monitoring Stations/State and Local Air Monitoring Stations (NAMS/SLAMS) with 12 km gridded output from the Models-3/Community Multiscale Air Quality (CMAQ) model.  Daily predictions are available at the 2000 US Census Tract centroid locations over the eastern U.S. for 2001-06 (please see DSMetadataAir file for exact coverages).  

Beginning in 2007, predictions are provided at 2010 US Census Tract locations over the entire conterminous U.S..  The date (month/last two digits of year) of the fusion runs is contained in the file names for the surfaces. For each day of the year, the predictive filesinclude the following variables (see DSMetadataAir file for more information on FIPS codes and other variables):