Intense cooling of a warm-core ring can cause the ring to sink under the surrounding fluids. A simple model of this process in a two and one-half layer (two active and one passive layer) ocean consisting of an inviscid Boussinesq fluid on an f-plane is presented. The model assumes that the cooling is limited to just the ring and occurs in such a way as to maintain a uniform density throughout the ring. This special cooling allows the results for various ring densities to be connected through the conservation of potential vorticity. The analytic solution that is derived for this model is examined to establish the physical processes accompanying the cooling and sinking of a ring. / Results show that warm-core rings can sink in a matter of days when exposed to typical cold air outbreaks of 500 to 1000 W m('-2). The model predicts that when the ring sinks it is overwashed completely, but this overwashing layer is very thin near the center of the ring. Thus the overwashing fluid would slow (but not eliminate) the cooling of the ring. Further analysis of the system assuming that the ring continues to be cooled after sinking shows that the overwashing fluids spiral in towards the center of the ring. These spiral trajectories steepen as the cooling rate increases, achieving spiral angles approaching those observed in Gulf Stream rings for cooling rates of about 1000 W m('-2). It is proposed that this mechanism can lead to the formation of streamers when one portion of the overwashing fluid has been passively marked with a visible tracer such as temperature or chlorophyll. / It is shown that the fluid that initially overwashes the ring originates under the ring, and not from outside the ring. When the ring sinks, this fluid is pushed out to the edge of the ring and spun up in the process. The theory further provides a mechanism for the entrainment of shelf-water organisms that are observed in warm-core rings. / Source: Dissertation Abstracts International, Volume: 48-03, Section: B, page: 0688. / Thesis (Ph.D.)--The Florida State University, 1987.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_76085 |
| Contributors | CHAPMAN, RICKEY DAVID., Florida State University |
| Source Sets | Florida State University |
| Detected Language | English |
| Type | Text |
| Format | 84 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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