AbstractHigh-resolution global measurement of the near-surface wind field over the ocean's surface is of critical importance in weather forecasting and in many oceanographic and meteorological studies. Such measurements can be provided by space-borne radar scatterometers. Scatterometers make indirect measurements of the wind by first measuring the surface radar backscatter from which the wind vector is“retrieved”or estimated. A new model-based technique for wind estimation promises improved measurement accuracy. This method is based on a mesoscale model for the near-surface oceanic wind field. The wind field model represents a trade-ofr between modelling accuracy and computational complexity in the estimation procedure. It is based on the geostrophic approximation and simplistic assumptions about the wind field vorticity and divergence, but includes ageostrophic winds. Simulation of oceanic wind fields and the scatterometer measurement system played a key role in the development and evaluation of the model. In this paper, the development and evaluation of the wind field model is described. The role of simulation in performing trade-offs between the model accuracyand the computational complexity of the model-based estimation procedure is discussed. The model development is an excellent case study of how modelling can be applied to improve the performance of a complex measurement system, and how simulation can be applied to develop and evaluate modelling techniques. A brief comparison of wind estimates made from simulated measurements and estimates based on actual measurements made by the SKASAT scatterometer is provided.