Upper ocean thermal structure forecast evaluation of a model using synoptic data

Abstract

A one-dimensional model (Camp, 1976) is used to simulate ocean thermal structure response to synoptic scale atmospheric forcing data at six loca­tions for a period of 20 days in August 1974 and 40 days from 21 November to 31 December 1974. The atmospheric forcing data (Solar Radiation, Total Heat Flux and Marine Winds) were obtained from Fleet Numerical Weather Cen­tral (FNWC) Primitive Equation and Marine Wind Models. Data used to initialize and verify the ocean thermal structure originated from bathythermograph data stored at FNWC. Length of simulation ranged from 72 hours to 36 days and was limited by the length of continuous historical data available for study. Results show the forcing functions contain sufficient resolution to define diurnal and synoptic time scale events. When the model is run using these forcing functions it produces changes in the mixed-layer depth and mixed-layer temperature on the same time scales. The magnitude of these changes ranged typically from diurnal fluctuations of 20 m/day and .3°C during summer conditions to synoptic scale deepening of 50 m and cooling by 2°C in 36 days during winter conditions. These results were verified when observations were present in this area. The capability now exists to produce real time dynamic ocean thermal profiles in areas of infrequent observations and also to forecast changes in ocean thermal structure up to 72 hours from the time of an observation.