Impacts on the global ocean circulation from vertical mixing and a collapsing ice sheet
Abstract:The current view of the global meridional overturning circulation (MOC) is one where the Atlantic is a dominant basin for deep water formation, but with the potential for bipolar seesaws between the Southern Ocean and the North Atlantic during catastrophic freshening events in either hemisphere. Here we investigate the stability of this paradigm through the response of an intermediate complexity coupled climate model, set in an oceanically more sensitive glacial configuration, to variation in the vertical mixing rates. It is found that the convective basin is set by the upper ocean diffusivity, with higher such diffusivities leading to a Pacific-dominated MOC. The upper ocean diffusivity is found to have a larger impact on the MOC than catastrophic flood events. It is known that deep ocean mixing rates were enhanced during glacial periods due to greater deep ocean tidal dissipation in the shallower oceans, with less extensive continental shelves. It is hypothesized that, combined with modified atmospheric states, there has been potential for the MOC to significantly alter between different glacial periods.
Document Type: Research Article
Publication date: March 1, 2011
More about this publication?
- The Journal of Marine Research publishes peer-reviewed research articles covering a broad array of topics in physical, biological and chemical oceanography. Articles that deal with processes, as well as those that report significant observations, are welcome. In the area of biology, studies involving coupling between ecological and physical processes are preferred over those that report systematics. Authors benefit from thorough reviews of their manuscripts, where an attempt is made to maximize clarity. The time between submission and publication is kept to a minimum; there is no page charge.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- ingentaconnect is not responsible for the content or availability of external websites