Anders Malmberg, avd för matematisk statistik, Lund A Statistical Model for Wind Fields in The North Atlantic Ocean Abstract Measurements of sea conditions over large areas by satellites have made it possible to compare forecasts with the actual conditions at sea. Marine operations and unconventional transports, which are sensitive to sea conditions, must have reliable and actual information of these. In this project we aim to find a model for the sea wind and use this to update future forecasts when new satellite measurements are done. Modeling a large-scale process like this causes many difficulties and a traditional space-time process is not suitable. Hence we have to reduce to number of states. This we do by adopting a physical model for the wind process, which implies that the wind process is composed by a finite set of principal components. The statistical model is temporally dynamic and spatially descriptive. This is achieved by assuming an AR(1) model for the time dynamics with spatially colored noise. In this framework, with a measurement equation of physical phenomena, which is described by a physical-statistical model the Kalman filter naturally comes at hand. Our first model will be estimated upon forecasted data only and in discrete time.