The report discusses atmospheric effects, relevant for radar and electro optic wave propagation, and how they can be modelled in wave propagation algorithms. The report proposes which models that need to be updated and makes suggestions on how wave propagation and the impact of atmosphere effects are best modelled. The main content of a future research project is also outlined. The wave propagation models can be used to estimate detection ranges for radar and EO sensor systems, and for radio communication. The models can also be used to evaluate detection ranges for hostile radar and EO systems. The electromagnetic properties of the atmosphere can be determined by local weather observations or by the use of numerical weather predictions. Numerical weather predictions can be used to predict the wave propagation properties of the atmosphere, which can be used in tactical decision aids in the planning of the tactical behaviour. A discussion with Finland, Denmark, Norway and US, regarding the content of a common project on the topic of radar wave propagation in the Baltic Sea, within the framework of International Cooperative Engagement Program for Polar Research (ICE-PPR) is in progress. Discussions are also taking place with US about a common, bi-lateral project, covering broader aspects of wave propagation in the atmosphere.