Abstract
Detailed meteorological measurements are used, together with fine-scale measurements of the density structure in a reservoir, to show that differential deepening of the diurnal mixed layer may occur as a result of a horizontal spatial variability in the wind stress. In the study, a one-dimensional integral model is used to simulate the energetics of mixed-layer deepening. A simple algorithm to simulate temperature changes due to horizontal advection is incorporated into the model. The model simulation shows that, during the study period, shear production was the major source of turbulent kinetic energy for deepening, but the wind duration was sufficiently short so that the mixed-layer depth closely reflected the local wind stress, even though the Wedderburn number was near unity. The horizontal density gradients set up by the increased deepening in the exposed region of the reservoir resulted in a horizontal flow driven by gravity, with typical overflow velocities of approximately 0·02 m s-1.
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© 1986 CSIRO — Australia
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Parker, G.J., Imberger, J. (1986). Differential Mixed-layer Deepening in Lakes and Reservoirs. In: De Deckker, P., Williams, W.D. (eds) Limnology in Australia. Monographiae Biologicae, vol 61. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-4820-4_3
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DOI: https://doi.org/10.1007/978-94-009-4820-4_3
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