“…Numerous publications have emphasized the importance of describing the temporal and spatial attributes of PM2.5 concentration levels measured by ambient air monitors [26,33,37,49,71,[85][86][87][88] and by AOD-PM2.5 in areas with and without air monitors [3, 15, 20, 22, 48, 52, 57-59, 61, 63, 67, 71, 78, 80, 81, 84, 89-93]. Our interdisciplinary research team, with members from the Battelle Memorial Institute, the U.S. Centers for Disease Control and Prevention (CDC), funded Environmental Public Health Tracking (EPHT) programs at the Maryland Department of Health and the New York State Department of Health, and the EPA initially developed the baseline PMB and subsequently assembled the four experimental AOD-PM2.5 concentration level fused surfaces, by statistically combining PM2.5 monitor readings with National Aeronautics and Space Administration (NASA) AOD data from the MODerate Resolution Imaging Spectroradiometer (MODIS) instrument on the Aqua and Terra satellites and CMAQ PM2.5 model estimates [94][95][96] for the New York City [32] and Baltimore [3,84] study areas.…”