Analysis of high-resolution COAMPS with observed METOC data to demonstrate atmospheric impact on EM propagation

Current U.S. Navy Special Warfare and submarine concepts of operations (CONOPS) dictate that in-situ environmental data collection is limited or not possible. Therefore, predicted data from operational models, such as the Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS), are essential to estimate the impacts of environmental conditions on the detection of enemy targets and counter-detection by radar and optical sensors. This study compares the use of high-resolution COAMPS data and in-situ shipboard and rawinsonde measurements for detection prediction purposes. The evaluation is based on data from Fleet Exercise SILENT HAMMER conducted off the Southern California coast near San Clemente Island in October 2004. An instrumented vessel was used for continuous surface layer data collection and frequent rawinsonde launches. COAMPS meteorological predictions were obtained at 3- and 9-km resolutions. The shipboard and COAMPS data provided refractivity profiles that were then used with propagation models within the BUILDER and AREPS graphical user interfaces to obtain signal-to-noise and propagation loss versus range diagrams. An increase in the horizontal resolution of COAMPS from 9 to 3 km did not significantly improve the prediction of meteorological variables within the lower marine boundary layer. However, counter-intuitively, the higher resolution did slightly improve detection range estimates. http://archive.org/details/analysisofhighre109452052 Approved for public release; distribution is unlimited.