Electromagnetic (EM) signal propagation in marine environments such as the Baltic Sea is strongly affected by atmospheric refractivity, which is shaped by stable boundary-layer conditions and sharp near-surface temperature and humidity gradients. These conditions can produce atmospheric ducting, causing anomalous propagation ranges and shadowed regions. Predicting such effects depends on how well Numerical Weather Prediction (NWP) models represent near-surface stability. This project requests compute and storage resources to run high-resolution simulations covering the Intensive measurement campaign conducted over the Baltic Sea from 26 May to 9 June 2026. Simulations use the coupled atmosphere-wave-ocean (AWO) system, integrating the Weather Research and Forecasting (WRF) model, the WaveWatch III (WW3) wave model, and the NEMO ocean model via the OASIS3-MCT coupler. Multiple simulations will be performed using different surface-layer parameterizations, to evaluate their impact on simulated refractivity profiles and ducting conditions during the campaign period. Model output will be compared against campaign observations to assess surface-layer uncertainty and improve NWP-based characterization of EM propagation conditions.