Investigation of the Influences of the Mixed-Layer Depth During the Cooling Season
Abstract
An analysis of bathythermograph data recorded at Ocean Station Papa (latitude 50N, longitude 145W) during the cooling season (October through December) indicates that the annual deepening and subsequent decay of the seasonal thermocline is accompanied by many random fluctuations. The physical processes causing the decay and the fluctuations in the mixed-layer depth are examined and qualitatively evaluated. The Tukey spectrum analysis programmed for the CDC 1604 electronic digital computer was used in analysis of oscillations at the bottom of the mixed layer to determine the distribution of wave energy for series of data taken at hourly intervals. An energy peak centered near 12 hours was observed to predominate, and this energy is equivalent to that of a 12-hour interval wave with height of 27.0 feet. The computer was also used to select the significant meteorological and oceanographic parameters which could be used to predict a change in the mixed-layer depth by use of the BIND 07 multiple regression program. The most significant parameter was sea surface temperature. The best correlation coefficient for this parameter occurred for lags of zero to 12 hours. The results of the analysis support the theory that convection is the physical process which causes the seasonal decay of the thermocline during the cooling season and that short-term fluctuations of the mixed-layer depth are due primarily to internal waves.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1962
- Accession Number
- AD0277573
Entities
People
- Donald H. Edgren
- John J. Macpherson
Organizations
- Naval Postgraduate School