Turbulent energy production and entrainment at a highly stratified estuarine front
MetadataShow full item record
Rates of turbulent kinetic energy (TKE) production and buoyancy flux in the region immediately seaward (~1 km) of a highly stratified estuarine front at the mouth of the Fraser River (British Columbia, Canada) are calculated using a control volume approach. The calculations are based on field data obtained from shipboard instrumentation, specifically velocity data from a ship mounted acoustic Doppler current profiler (ADCP), and salinity data from a towed conductivity-temperature-depth (CTD) unit. The results allow for the calculation of vertical velocities in the water column, and the total vertical transport of salt and momentum. The vertical turbulent transport quantities (inline equation, inline equation) can then be estimated as the difference between the total transport and the advective transport. Estimated production is on the order of 10−3 m2 s−3, yielding a value of ɛ(νN2)−1 on the order of 104. This rate of TKE production is at the upper limit of reported values for ocean and coastal environments. Flux Richardson numbers in this highly energetic system generally range from 0.15 to 0.2, with most mixing occurring at gradient Richardson numbers slightly less than inline equation. These values compare favorably with other values in the literature that are associated with turbulence observations from regimes characterized by scales several orders of magnitude smaller than are present in the Fraser River.
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 109 (2004): C05004, doi:10.1029/2003JC002094.
Showing items related by title, author, creator and subject.
Manucharyan, Georgy E.; Caulfield, C. P. (2014-12)We consider experimentally an initially quiescent and linearly stratified fluid with buoyancy frequency NQ in a cylinder subject to surface-stress forcing from a disc of radius R spinning at a constant angular velocity Ω. ...
Cenedese, Claudia; Linden, P. F. (Cambridge University Press, 2014-07-11)A model of the total volume flux and entrainment occurring in two coalescing axisymmetric turbulent plumes is developed and compared with laboratory experiments. The dynamical evolution of the two plumes is divided into ...
Wells, Mathew; Cenedese, Claudia; Caulfield, C. P. (American Meteorological Society, 2010-12)The authors explore the theoretical and empirical relationship between the nonlocal quantities of the entrainment ratio E, the appropriately depth- and time-averaged flux coefficient Γ, and the bulk Froude number Fro in ...