| Summary: | An objective technique which produces regularly spaced fields of winds, temperatures, humidity, wind stress and sensible and latent heat fluxes is developed. It combines in-situ Volunteer Observing Ship (VOS) data and remotely sensed data from SEASAT during the analysis period, July 7-October 10, 1978 for the north Atlantic. The objective technique is a variational method which reduces a set of several constraints expressing closeness to input data, climatology and kinematics. Analysis results are presented for monthly and 5-day periods during the analysis period. Seasonal (3 month) means of temperature, humidity, and flux determined by the monthly and 5-day results are comparable. However, 5-day wind results had much smaller errors than the monthly mean winds averaged over the 3-month period. Variability of the 5-day results indicates high variability of temperatures, humidity, and heat fluxes in the vicinity of the Gulf Stream. Sea surface temperature (SST) variability is high in the eastern Atlantic and is coupled to wind driven ocean variability in the region. Heat fluxes are coupled to and determined by various parameters. The variations for both sensible and latent heat fluxes in the extra-tropics are determined by the position and strength of the circulation of the semi-permanent high pressure system. Some evidence is also found to indicate dependence of SST on latent heat. In the tropics, the heat fluxes are determined by a combination of factors, including zonal wind and SST. Estimates of errors due to insufficient sampling and random data are presented for the monthly results. The sampling and random errors in wind stress are in the range of 10%-20% of the mean values. For the sensible and latent heat fluxes, the sampling errors are about half of those attributable to random errors. Because of the difference operator used in diagnosing heat fluxes, these fluxes are found to be more sensitive to the accuracies of temperatures and humidity than accuracies of winds. Source: Dissertation ...
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