Skin cancer, the most common type of cancer in the U.S., represents a significant and growing public health burden. Annually, skincancer costs an estimated $1.7 billion to treat and results in $3.8 billion in lost productivity. The most severe type of skin cancer,melanoma, causes over 75% of skin cancer deaths. According to the National Cancer Institute (NCI), approximately 76,690 people willbe diagnosed with and 9,480 people will die of melanoma in 2013. The lifetime risk of melanoma in the U.S. has grown dramatically,from 1 in 1500 in the 1930s to 1 in 58 in 2009.The Environmental Public Health Tracking Network (the Tracking Network) at the Centers for Disease Control and Prevention(CDC) has the congressional mandate to track and report environmental hazards and the related health endpoints include melanoma.Although exposure to UV radiation is well-known to be the most important cause of skin cancer, Tracking currently does not provideany indicators of UV exposure. We propose to enhance Aura data products to provide county-level UV exposure information forTracking to develop environmental indicators and measures and conduct epidemiological and linkage studies. This applied scienceproposal corresponds to the NASA Applied Science Program application area of Health and Air Quality, which is solicited as part ofthe Aura Science Team proposal call.By integrating ground observations and atmospheric chemical transport model simulations, we aim at enhancing the existing OMIsurface UV (OMUVB) product by better accounting for the impact of absorbing aerosols in the retrieval of surface UVB irradianceand erythemal doses. In addition, OMUVB uncertainties due to SO2 and NO2 absorption will be analyzed, and will be correctedprimarily in polluted urban regions. The conversion from the dose rate estimated at OMI overpass time to that at the local noon timeand eventually to the daily-average dose will also account for diurnal change of aerosols. After evaluating the accuracy of the enhancedOMUVB product with ground measurements, we will spatially match OMUVB exposure doses to 3,100 U.S. counties and study theirassociation with county-level melanoma incidences reported by NCI. Major confounding factors such as indoor tanning use, education,poverty, health insurance, and rural-urban status will also be processed and included in our epidemiological model. Finally, we willwork closely with Tracking to develop UV exposure indicators and measures as well as detailed documentation for public release onthe Tracking Network.Our interdisciplinary team brings together experienced remote sensing experts, environmental exposure modelers, and epidemiologists.Through multiple collaboration efforts, the external investigators have developed a long-lasting and productive work relationship withCDC scientists. The strong commitment and direct involvement of key Tracking personnel will ensure the outcome of this project tomaximally benefit the operation of this important decision support system as well as a smooth transition of enhanced Aura scienceproducts to Tracking end users beyond the remote sensing community.