Real-time Enhancement of a Climatology Or Forecast of Ocean Thermal Structure Using Observed Ocean Temperatures

Book excerpt: Vertical temperature profiles observed in the eastern North Pacific were used to examine the feasibility of extrapolating an observation from one location to another. The technique, referred to as simple enhancement, is a special case of the Gandin (1963) optimum interpolation methodology. Application to Navy ASW (Antisubmarine Warfare) operations is considered. The technique requires the use of a trial value and a local observation. Trial values are obtained from a climatology and a synoptic analysis/forecast system provided by the Fleet Numerical Oceanography Center. An enhanced temperature profile is calculated by adding an observed anomaly (i.e., observation minus trial value) to the trial value at the desired location. Calculations of mean and RMS errors indicate that simple enhancement can provide a closer estimate to actual conditions than unenhanced climatology. The mixed layer depth cannot be extrapolated accurately to new locations presumably due to mesoscale eddies, fronts, internal waves and small scale fluctuations at the base of the mixed layer. Experiments at different locations and seasons would be required for a complete assessment of the application to ASW operations. Originator supplied keywords include: Ocean thermal structure; Optimal interpolation; Mixed layer; Ocean analysis; Ocean prediction.