DIFFUSION AND DEf'tBITION OF FLOATING POLLLTANTS
38 1
By way of an example consider I; = I cm sec-', h = 5 km; Q = 1 ton =
lo6 gm, U = 20 cm sec- ', K = lo3 cm2 sec- I. This yields a maximum deposit of D,,, = 50 gm/km, or about 2 alewives per kilometre shoreline, at a
distance of about s = 2500 km from the point of release, clearly a ridiculous
result. It shows that diffusion alone will not cause significant beach deposition for release distances of a few kilometres: an onshore drift must bring the
alewives in closer, or they must die much closer to shore if they are to be
washed up anywhere. The physical reason is of course that a cloud of
floating objects grows only slowly; the diffusive power of Langmuir circulations is quite modest.
REFERENCFS
Carslaw. ti. S., and Jaeger. J. C. (1959). "Conduction of Heat in Solids,'' 510 pp. Oxford Univ.
Csanady, G . T. (1963). Turbulent diflusion in Lake Huron. J . Fluid Mvrh. 17. 360 -384.
Csanady. G. T. (1965). Windrow studies. ' * Baie du Dort Report, 1965." PR 26. pp. 60 W2. Univ.
Csanady, G. T. (1970). Dispersal of effluents in the Great Lakes. Wurer Res. 4, 79- 114.
Csanady. G. T. (1972). The coastal boundary layer in Lake Ontario. Pan I, the Spring regime. J.
Phys. Orwnoqr. 2. 41 -53.
Csanady. C. T.. and Page, B. (1969). Windrow observations. ' * Dynamics and Diffusion in the
Great Lakes." pp. 3-38. Dep. Mech. Enp.. Univ. of Waterloo, Waterloo. Canada.
Dorman. C. E.. and Mollo-Christensen. E. (1973). Observations of the structure of moving gust
patterns over a water surface ("cat's paws"). J . Phys. Oreunogr. 3. 120- 132.
Lamb, H. (1932). "Hydrodynamics," 738 pp. Cambridge Univ. Press, London and New York.
Langmuir, I. (1938). Surface motion of water induced by wind. Science 87. 119-123.
Lighthill, M. J. (1963). In "Laminar Boundary Layers" (L. Rosenhead. ed.). Oxford Univ.
Press. London and New York.
McLeish. W . (1968). On the mechiinism of wind-slick generation. Deep-Seu Res. Ocunnogr.
Ahstr. IS. 461 -469.
Okubo. A. (1970). Horizontal dispersion of floatable particles in the vicinity of velocity singularities such as convergences. Deep-sea Res. Oceunugr. Ahstr. 17, 44-454.
RagotAie, K. A. (1962). EfTect of air stability on the development of wind waves on lakes.
Limnol. Orcwioyr. 7 . 248-251.
Scott. J. T., Myer, G. E., Stewart. R., and Walther, E. G. (1969). On the mechanism of Langmuir
circulations and their role in epilimnion mixing. Lininol. Ocewwyr. 14. 4Y3 SO3.
Stanley. J. G . (1969). Seasonal changes in thc elcctrolyte metabolism in the alewife. A I W J
pseuh/~urengus in Lake Michigan. Proc. ('on/: Grmt Lukcs Res., I2rh (Inr. ,458. (;fC3(lt Lokc,.\
Rcs., Ann .4rhw. M i d i . ) pp. 91-97.
Wipperman. F. (1959). Zur Erdboden-Randbedingung hei atmosphhrirheo Diffusionsprozessen. Britr. P h ~ s .
Afnius. 32. 43 -52.
Press. London and New York.
of Toronto Great Lakes Inst.. Toronto.
"
38 1
By way of an example consider I; = I cm sec-', h = 5 km; Q = 1 ton =
lo6 gm, U = 20 cm sec- ', K = lo3 cm2 sec- I. This yields a maximum deposit of D,,, = 50 gm/km, or about 2 alewives per kilometre shoreline, at a
distance of about s = 2500 km from the point of release, clearly a ridiculous
result. It shows that diffusion alone will not cause significant beach deposition for release distances of a few kilometres: an onshore drift must bring the
alewives in closer, or they must die much closer to shore if they are to be
washed up anywhere. The physical reason is of course that a cloud of
floating objects grows only slowly; the diffusive power of Langmuir circulations is quite modest.
REFERENCFS
Carslaw. ti. S., and Jaeger. J. C. (1959). "Conduction of Heat in Solids,'' 510 pp. Oxford Univ.
Csanady, G . T. (1963). Turbulent diflusion in Lake Huron. J . Fluid Mvrh. 17. 360 -384.
Csanady. G. T. (1965). Windrow studies. ' * Baie du Dort Report, 1965." PR 26. pp. 60 W2. Univ.
Csanady, G. T. (1970). Dispersal of effluents in the Great Lakes. Wurer Res. 4, 79- 114.
Csanady. G. T. (1972). The coastal boundary layer in Lake Ontario. Pan I, the Spring regime. J.
Phys. Orwnoqr. 2. 41 -53.
Csanady. C. T.. and Page, B. (1969). Windrow observations. ' * Dynamics and Diffusion in the
Great Lakes." pp. 3-38. Dep. Mech. Enp.. Univ. of Waterloo, Waterloo. Canada.
Dorman. C. E.. and Mollo-Christensen. E. (1973). Observations of the structure of moving gust
patterns over a water surface ("cat's paws"). J . Phys. Oreunogr. 3. 120- 132.
Lamb, H. (1932). "Hydrodynamics," 738 pp. Cambridge Univ. Press, London and New York.
Langmuir, I. (1938). Surface motion of water induced by wind. Science 87. 119-123.
Lighthill, M. J. (1963). In "Laminar Boundary Layers" (L. Rosenhead. ed.). Oxford Univ.
Press. London and New York.
McLeish. W . (1968). On the mechiinism of wind-slick generation. Deep-Seu Res. Ocunnogr.
Ahstr. IS. 461 -469.
Okubo. A. (1970). Horizontal dispersion of floatable particles in the vicinity of velocity singularities such as convergences. Deep-sea Res. Oceunugr. Ahstr. 17, 44-454.
RagotAie, K. A. (1962). EfTect of air stability on the development of wind waves on lakes.
Limnol. Orcwioyr. 7 . 248-251.
Scott. J. T., Myer, G. E., Stewart. R., and Walther, E. G. (1969). On the mechanism of Langmuir
circulations and their role in epilimnion mixing. Lininol. Ocewwyr. 14. 4Y3 SO3.
Stanley. J. G . (1969). Seasonal changes in thc elcctrolyte metabolism in the alewife. A I W J
pseuh/~urengus in Lake Michigan. Proc. ('on/: Grmt Lukcs Res., I2rh (Inr. ,458. (;fC3(lt Lokc,.\
Rcs., Ann .4rhw. M i d i . ) pp. 91-97.
Wipperman. F. (1959). Zur Erdboden-Randbedingung hei atmosphhrirheo Diffusionsprozessen. Britr. P h ~ s .
Afnius. 32. 43 -52.
Press. London and New York.
of Toronto Great Lakes Inst.. Toronto.
"