On the abyssal temperatures of the world oceans

• Main Author: Olson, Boyd Ellertson
• Other Authors: Patullo, June G., Anderson, Norman H., Smith, Robert L., Tatom, John F., Newton, Byron L., Oceanography, Oregon State University. Graduate School
• Format: Doctoral or Postdoctoral Thesis
• Language: English; unknown
• Published: Oregon State University
• Subjects: Ocean temperature; Benthos; Antarc*; Antarctic
• Online Access: https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/xw42nc18d

In comparison with solar radiation, the energy of geothermal heat flowing through the sea bottom is extremely small; nevertheless, this energy is not insignificant in the circulation of the bottom water. Calculations indicate that in the deep basins of the South Atlantic the water volume transport necessary to remove this heat is at least one-tenth of the total northward flow of Antarctic Bottom Water. Plots of mean values of near bottom salinity and oxygen versus mean potential temperatures help to trace the movement of the bottom water. Geothermal and adiabatic warming associated with downslope flow combine to produce a deep temperature (in situ) minimum in portions of most of the deep basins of the world. Adiabatic or near adiabatic temperature gradients have been measured near the bottom in many of these basins. Evidence of superadiabatic gradients from temperature measurements made with reversing thermometers is inconclusive; however, careful measurements with closely spaced thermometers suggest that such gradients do exist over vertical distances of a few hundred meters in some of the deepest basins. Decreasing potential density with depth, as found in some of the Atlantic Basins in association with sharp temperature and salinity gradients, is not necessarily an indication of unstable equilibrium. This is demonstrated by the results of stability calculations in the manner prescribed by Hesselberg and Sverdrup (1915).