ESTONIAN ACADEMY
PUBLISHERS
eesti teaduste
akadeemia kirjastus
PUBLISHED
SINCE 1952
 
Earth Science cover
Estonian Journal of Earth Sciences
ISSN 1736-7557 (Electronic)
ISSN 1736-4728 (Print)
Impact Factor (2020): 0.789

A modified Ekman layer model; pp. 123–129

Full article in PDF format | doi: 10.3176/earth.2011.2.06

Authors
Jaak Heinloo, Aleksander Toompuu

Abstract
A modification of the Ekman layer that is able to systematically account for the effects of curvature of the velocity fluctuation streamlines is developed, using the description of turbulent motions. These effects are accounted for through the average vector product of the velocity fluctuations and the local curvature vector of their streamlines at each flow field point. It is shown that this approach enables quantifying the impact of several phenomena (such as the Stokes drift or the incessant generation of vortices with a prevailing orientation of rotation, intrinsic to surface-driven geophysical flows) on the formation of the Ekman layer. The outcome of the suggested modification is compared with the relevant data measured in the Drake Passage.
References

Chereskin, T. K. 1995. Direct evidence for an Ekman balance in the California Current. Journal of Geophysical Research, 100, 18261-18269.
doi:10.1029/95JC02182

Chereskin, T. K. & Price, J. F. 2001. Ekman transport and pumping. In Encyclopedia of Ocean Sciences (Steele, J., Thorpe, S. & Turekian, K., eds), pp. 809-815. Academic Press.
doi:10.1006/rwos.2001.0155

Coleman, G. N., Ferziger, J. H. & Spalart, P. R. 1990. A numerical study of the turbulent Ekman layer. Journal of Fluid Mechanics, 213, 313-348.
doi:10.1017/S0022112090002348

Cushman-Roisin, B. 1994. Introduction to Geophysical Fluid Dynamics. Prentice Hall, 320 pp.

Davis, R., deSzoeke, R., Halpern, D. & Niiler, P. 1981. Variability in the upper ocean during MILE. Part 1: The heat and momentum balances. Deep-Sea Research, 28A, 1427-1451.
doi:10.1016/0198-0149(81)90091-1

Ekman, V. W. 1905. On the influence of the Earth’s rotation on ocean currents. Arkiv för Matematik, Astronomi och Fysik, 2, 1-53.

Heinloo, J. 2004. The formulation of turbulence mechanics. Physics Review E, 69, 056317.
doi:10.1103/PhysRevE.69.056317

Huang, N. E. 1979. On surface drift currents in the ocean. Journal of Fluid Mechanics, 91, 191-208.
doi:10.1017/S0022112079000112

Lenn, Y.-D. & Chereskin, T. K. 2009. Observations of Ekman currents in the Southern Ocean. Journal of Physical Oceanography, 39, 768-779.
doi:10.1175/2008JPO3943.1

Madsen, O. S. 1977. A realistic model of the wind-induced Ekman boundary layer. Journal of Physical Oceanography, 7, 248-255.
doi:10.1175/1520-0485(1977)007<0248:ARMOTW>2.0.CO;2

Phillips, O. M. 1977. Dynamics of the Upper Ocean. Cambridge University Press, 336 pp.

Price, J. F. & Sundermeyer, M. A. 1999. Stratified Ekman layers. Journal of Geophysical Research, 104(C9), 20467-20494.
doi:10.1029/1999JC900164

Price, J. F., Weller, R. A. & Pinkel, R. 1986. Diurnal cycling: observations and models of the upper ocean response to diurnal heating, cooling, and wind mixing. Journal of Geophysical Research, 91, 8411-8427.
doi:10.1029/JC091iC07p08411

Price, J. F., Weller, R. A. & Schudlich, R. R. 1987. Wind-driven ocean currents and Ekman transport. Science, 238, 1534-1538.
doi:10.1126/science.238.4833.1534

Richman, J. G., deSzoeke, R. A. & Davis, R. E. 1987. Measure­ments of near-surface shear in the ocean. Journal of Geophysical Research, 92, 2851-2858.
doi:10.1029/JC092iC03p02851

Schudlich, R. R. & Price, J. F. 1998. Observations of seasonal variation in the Ekman layer. Journal of Physical Oceanography, 28, 1187-1204.
doi:10.1175/1520-0485(1998)028<1187:OOSVIT>2.0.CO;2

Weller, R. A. 1981. Observations of the velocity response to wind forcing in the upper ocean. Journal of Geophysical Research, 86, 1969-1977.
doi:10.1029/JC086iC03p01969

Weller, R. A., Rudnick, D. L., Eriksen, C. C., Polzin, K. L., Oakey, N. S., Toole, J. W., Schmitt, R. W. & Pollard, R. T. 1991. Forced ocean response during the Frontal Air–Sea Interaction Experiment. Journal of Geophysical Research, 96, 8611-8638.
doi:10.1029/90JC02646

Wijffels, S., Firing, E. & Bryden, H. L. 1994. Direct observations of the Ekman balance at 10° N in the Pacific. Journal of Physical Oceanography, 24, 1666-1679.
doi:10.1175/1520-0485(1994)024<1666:DOOTEB>2.0.CO;2

Zikanov, O., Slinn, D. N. & Dhanak, M. R. 2003. Large-eddy simulations of the wind-induced turbulent Ekman layer. Journal of Fluid Mechanics, 495, 343-368.
doi:10.1017/S0022112003006244
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