The salinity extrema of the world ocean

• Main Author: Ingham, Merton C., 1930-
• Other Authors: Weyl, Peter K., Oceanography, Oregon State University. Graduate School
• Format: Doctoral or Postdoctoral Thesis
• Language: English; unknown
• Published: Oregon State University
• Subjects: Ocean; Salinity; Southern Ocean
• Online Access: https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/3b591d783

The principal salinity extrema and extremum surfaces of the world ocean are described by the analysis and plotting of data from 885 hydrographic stations in the three major oceans, the Southern Ocean, and the American Mediterranean Sea. The distributions of salinity, temperature, depth, and density along the extremum surfaces, plotted on world ocean charts, are the main elements of the description of the extremum surfaces. In addition, the distributions of two new parameters of the salinity structure, the intensity of the intermediate depth salinity minimum and the slope ratio of the T-S curve, are used to supplement the description of the extremum surfaces. The intensity of the salinity minimum is a measure of the perturbation of the salinity versus depth curve due to the presence of the minimum. The slope ratio of the T-S curve is a comparison of the slope of the observed T-S curve with the slope of local isopycnal lines in the T-S field. It is shown that the distribution of the aforementioned parameters manifest characteristic differences in each of the three major oceans. The portrayal of the parameters along the salinity extremum surfaces proves to be an effective means of demonstrating some of the fundamental differences among the oceans. The T-S curves for the upper kilometer of water in regions showing decreasing temperatures and salinities with depth are found to coincide quite closely with constant slope ratio curves. This coincidence is the basis of a two-parameter description of the T-S curve which proves to be more accurate than the commonly used straightline approximation. The two parameters used in the description are the slope ratio and the salinity of the ten-degree intercept of the constant slope ratio curve which most closely coincides with the observed T-S distribution.