Evaluation of CASP (Computer Assisted Search Planning Program) Drift Predictions Near the New England Shelf/Slope Front

摘要

In June 1984 a series of experiments was conducted in which the drift predictions of the Coast Guard's operational search planning computer model (CASP) were evaluated. Three satellite-tracked drift buoys and a life raft were released and tracked for two 3-day periods at the New England Shelf/Slope Front. Their movement was compared with CASP drift predictions for simulated PIW's and a life raft for two sets of environmental data: historical currents and large-scale winds versus locally measured data. For the historical data, the observed drift errors were two to four times larger than drift errors calculated by CASP. The use of on-scene environmental data improved the predictions for PIW's to near the CASP-calculated drift errors, but not for the life raft. Significant differences in the surface currents occurred over 20 nautical miles and 3 to 5 days, which were not accounted for by the historical surface current files, and therefore increased the error in the drift prediction of CASP. Keywords: Probability of detection; Ocean surface currents; Search and rescue; Fronts; Satellite-tracked buoys; Ocean circulation; Drift prediction; CASP(Computer Assisted Search Planning); Continental Shelves; Continental slope; PIW(Persons in Water).