ALTIMETRIC SENSING OF CURRENTS: SPATIAL AVERAGING AND SAMPLING IMPACTS ON OCEAN ROUTING

Strategic ship routing impacts of various spatial resolutions associated with satellite-based altimetric sensing of ocean currents are evaluated. Underlying true current patterns are averaged to more aggregate grids, routes are chosen designed to exploit the currents from these aggregate estimates, and the underlying true current patterns are used to simulate relative fuel consumption on these routes. The underlying current patterns are produced from an advanced model of a spatially variable area of the North Atlantic Gulf Stream, and the route origins and destinations are confined to this region. The results indicate that the 5 x 5 degree spatial resolution of available data is too coarse to be of use in strategic routing in this area. However, the improved resolution that would be compatible with satellite altimeter systems would lead to positive fuel savings, and savings that are fairly close to those available if the underlying data were known in their finest detail. Sampling along geographically separated ground tracks can still lead to positive fuel savings, even in this spatially variable region. Impacts for practical applications are discussed.