An Integrated System Solution (ISS) for improved Atmospheric Transport and Diffusion (ATD) modeling of potential biochemical and nuclear hazards is proposed in support of the United States lead Federal agency for incidents of national significance. The Department of Homeland Security's Interagency Modeling and Atmospheric Assessment Center (IMAAC) at Lawrence Livermore National Laboratory, in partnership with the NASA Goddard Space Flight Center and the NASA Stennis Space Center, propose to integrate and benchmark the inclusion of satellite-derived data products into the suite of IMAAC models, focusing initially on aerodynamic roughness length, in order to improve their performance and to enhance decision support during potential atmospheric release events. The suite of IMAAC models, including meteorology and transport models, are the Decision Support Tools (DSTs) employed by IMAAC. IMAAC has asked NASA to focus on providing spatially distributed roughness length, one of the most important parameters in ATD modeling. Incorporation of roughness length into IMAAC will serve as a prototype for other secondary model parameters available from NASA. The proposed project relates to the Homeland Security application of national priority. Other applications, such as Air Quality and Disaster Management will also benefit from the project's results.