The Southern Ocean: Its Involvement in Global Change,

Abstract

Southern Ocean is the site of considerable water mass formation which cools and ventilates the modern world ocean. At the polar front zone, formation of cool, low salinity water sinks and spreads northward at intermediate depths limiting the downward penetration of the thermocline. Within the seasonal sea ice zone and along the margins of Antarctica, convection injects very cold oxygenated water into the deep and bottom ocean. These conditions developed as Antarctica shifted into its present configuration and grew a persistent glacial ice sheet, about 14 million years ago. The potential of the Southern Ocean to ventilate the deep and bottom ocean layers is related to occurrence of polynyas that form within the winter sea ice cover. Global climate changes would be expected to alter the polynya size and frequency. Under greenhouse-induced warming offshore polynyas may become less common as the static stability of the Southern Ocean mixed layer increases. This would diminish the Southern Ocean's cooling influence on the deep layers of the world ocean, resulting in a warmer deep ocean. The fate of coastal polynyas is less clear.

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1992
Accession Number
ADP007295

Entities

People

  • Arnold L. Gordon

Organizations

  • Lamont–Doherty Earth Observatory

Tags

DTIC Thesaurus Topics

  • Climate Change
  • Deep Oceans
  • Glaciers
  • Ice
  • Oceans
  • Polar Regions
  • Regions
  • Sea Ice
  • Southern Ocean
  • Water
  • Water Masses

Fields of Study

  • Environmental science

Readers

  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Oceanography.
  • Polar and Arctic Studies