The premise of the proposed project is that health hazard mitigation planning and public health disaster response can be improved by including environmental exposure characterization, through the application of Earth Observations (EO) and synthetic population modeling. Current health hazard mitigation planning at the federal and state level incorporates vulnerability mapping, such as the Centers for Disease Control and Preventions Social Vulnerability Index (SVI), that relies on static sociodemographic data to identify populations most likely to experience adverse health outcomes during and following a disaster. The proposed work will enhance these metrics of social vulnerability by developing a methodology for dynamic exposure estimates using EO combined with simulations of people’s movements through space and time. We focus on a case study application that evaluates exposure to temperature, flood water, and power outages during and following Hurricane Harvey and comparison to health data collected from syndromic surveillance systems at the Houston Health Department. Methods