Subtropical front

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A "subtropical front" is defined as a surface water mass boundary. It is a term used to describe a boundary, also known as a front, which is a: Narrow zone of transition between air masses of contrasting density, air masses of different temperatures or different water vapour concentrates.[1] It is also characterized by an unforeseen change in wind direction, and speed across its surface between water systems, which are based on temperature and salinity. The subtropical separates the more saline subtropical waters from the fresher sub-Antarctic waters.[2]

Subtropical Frontal Zone (STFZ)[edit]

Large seasonal cycle located on the eastern side of basins. It is made up of multiple weak sea surface temperature (SST) fronts, aligned northwest-southeast, spread over a large latitudinal span. On the far eastern side of basins, the subtropical frontal zone becomes narrower and temperature gradients stronger, but still much weaker than across the Dynamical Subtropical Frontal Zone.[3]

Structure of the Subtropical Frontal Zone[edit]

Resulting form positive wind stress curl. The areas of most positive wind stress curl are characterized by very weak sea surface temperature incline, and are likely consistent to regions of mode water.

Dynamical Frontal Zone[edit]

Sits at the southern limit of the saline subtropical waters on the western sides of basins. There are no water mass boundaries in correlation with the sea surface temperature (SST) fronts at the subtropical frontal zone at the surface of beneath.

Northern Subtropical Front[edit]

A subtropical front in the Pacific Ocean lying between 25° and 30° north latitude

North Atlantic Subtropical Fronts[edit]

Possess the characteristics of seasonal variability. Highest front occurrences are during early spring in the western region. Less front probability occurs in late spring to early summer in the eastern region. The strengths of the fronts differ with seasons, building strength when moving southward during the winter and spring, and weakening when moving northward during the summer. [4]

North Pacific Subtropical Fronts[edit]

Are occupied by wind driven submesoscale subduction. Due to the constant thermohaline circulation fronts, cold air flows near the surface and bottom of the ocean. There are alternating fluxes throughout the year, that is influenced by jet streams which causes temperatures in these areas to differ.[5]

Southern Subtropical Front[edit]

The boundary between warm, salty subtropical waters and Antarctic waters, found in all three ocean basins. A commonly used criterion found is that the salinity at a depth of 100m drops below 34.9 practical salinity units.

South Atlantic Subtropical Frontal Zone[edit]

Characteristics of the South Atlantic Subtropical Frontal Zone between 15°w and 5°e: It has been discovered that occurring within the subtropical frontal zone, is the conversion from subtropical to sub polar waters. In result, this coerces the South Atlantic Current flow and is surrounded by a distinct front. [6]

See also[edit]

References[edit]

  1. ^ http://amsedu.ametsoc.org/amsedu/wes/glossary.html
  2. ^ Graham, Robert M., and Agatha M. Boer. "The dynamical subtropical front." Journal of Geophysical Research: Oceans 118.10 (2013): 5676-5685.
  3. ^ Graham, Robert M., and Agatha M. Boer. "The dynamical subtropical front." Journal of Geophysical Research: Oceans 118.10 (2013): 5676-5685.
  4. ^ Ullman, D. S., P. C. Cornillon, and Z. Shan. "On the characteristics of subtropical fronts in the North Atlantic." Journal of Geophysical Research: Oceans (1978–2012) 112.C1 (2007).
  5. ^ Hosegood, P. J., M. C. Gregg, and M. H. Alford (2013), Wind-driven submesoscale subduction at the north Pacific subtropical front, J. Geophys. Res. Oceans, 118, 5333–5352, doi:10.1002/jgrc.20385
  6. ^ D. Smythe-Wright, P. Chapman, C.Duncombe Rae, L.V. Shannon, S.M. Boswell, Characteristics of the South Atlantic subtropical frontal zone between 15°W and 5°E, Deep Sea Research Part I: Oceanographic Research Papers, Volume 45, Issue 1, January 1998, Pages 167-192, ISSN 0967-0637, http://dx.doi.org/10.1016/S0967-0637(97)00068-X. (http://www.sciencedirect.com/science/article/pii/S096706379700068X)

External links[edit]