Research in this area is directed towards understanding and being able to describe the propagation of electric and magnetic fields in the sea and on the sea bed. One important activity is to measure and model the electromagnetic environment in the water column to enable, for example, the Swedish Armed Forces to calculate ranges for sensors and ship signatures. Other applications include determining, when charting the sea bed, the electrical properties of the sea bed and the underlying bedrock, e.g. in support of prospecting.