AS DETAILED IN THE ATTACHED ORIGINAL PROPOSAL THIS PROJECT WILL EVALUATE AND ENRICH THE UTILITY OF SNPP DATA FOR APPLIED SCIENCE RESEARCH. FOLLOWING THE SNPP S SCIENCE STRATEGY TO CONTINUE THE NASA S EOS DATA RECORD AND TO AVOID FUTURE POSSIBLE DISCONTINUITY OF USING NASA S DATA IN AIR QUALITY AND PUBLIC HEALTH APPLICATIONS OUR PROPOSED WORK HAS THE FOLLOWING TWO COMPONENTS. (1) PM2.5 AIR QUALITY APPLICATIONS. WE WILL (A) EVALUATE AND IMPROVE THE APPLICATION OF THE (MODIS-TYPE IF POSSIBLE) VIIRS AEROSOL PRODUCT FOR THE OPERATIONAL MONITORING OF PM2.5 AIR QUALITY IN REMOTE SENSING INFORMATION GATEWAY (RSIG) AT THE U.S. ENVIRONMENTAL PROTECTION AGENCY (EPA) (B) SUBSEQUENTLY TRANSFER RSIG S PM2.5 ESTIMATES TO THE ENVIRONMENTAL PUBLIC HEALTH TRACKING NETWORK (EPHTN) AT THE CENTERS FOR DISEASE CONTROL AND PREVENTION (CDC) AND (C) EVALUATE AND IMPROVE VIIRS-RSIG PM2.5 ESTIMATES FOR ENHANCED SPATIAL PREDICTIONS IN ON-GOING EPA-CDC EPHTN EFFORTS CURRENTLY USING CMAQ MODEL OUTPUT AND FILTER-BASED PM2.5 OBSERVATIONS FROM EPA-AQS. (2) PUBLIC HEATH (SKIN-CANCER-RELATED) APPLICATIONS. WE WILL INCORPORATE OMPS-BASED ESTIMATES OF SURFACE UVB IRRADIANCE AND ERYTHEMAL DOSES INTO THE CDC S EPHTN AND APPLY THEM IN BOTH PUBLIC HEATH ADVISORY AND SKIN CANCER RESEARCH. BY INTEGRATING GROUND OBSERVATIONS (AERONET) ATMOSPHERIC CHEMICAL TRANSPORT MODEL (GEOS-CHEM) SIMULATIONS