The Entrainment and Homogenization of Tracers within the Cyclonic Gulf Stream Recirculation Gyre.
Abstract
The distributions of tracer associated with the Northern Recirculation Gyre of the Gulf Stream (NRG) are studied to try to obtain information about the flow. An advective-diffusive numerical model is used whose streamlines consist of a gyre situated alongside a boundary current which inputs tracer into the domain. This is meant to simulate the lateral transfer of properties from the Deep Western Boundary Current (DWBC) to the NRG. Tracer is entrained into the model gyre as a plume which spirals across the streamlines, the characteristics of which depend on the flow parameters. Homogenization occurs at steady state, consistent with recently collected tracer data. The presence of vertical mixing is considered in an attempt to explain a difference between salinity and oxygen observed in the data. Comparison of the model results to the oxygen data is favorable, and leads to an estimate of the lateral and vertical diffusivity. The time dependent nature of freon is addressed using a coupled model of the deep water overflow process, advection-mixing in the DWBC, and subsequent entrainment into the NRG. Comparison with the data shows that very little freon has accumulated in the NRG, and that these processes effect the freon-11:freon-12 ratio as well. Keywords: Gulf Stream recirculation. (Theses).
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1987
- Accession Number
- ADA182341
Entities
People
- Robert Pickart
Organizations
- Woods Hole Oceanographic Institution