The effect of sea cliffs on inland encroachment of aeolian sand
The effect of sea cliffs on aeolian sand encroachment inland was monitored by means of traps measuring the sand transport and microanemometers measuring wind flow, because these are affected by the topography of the cliffs. Measurements were carried out on two cliffs in the southern coastal-plain of Israel: one 160 m and the second 240 m long, with front slope inclination of 30° to 40° and a height of 22-25 m. Results show that sand is incapable of climbing even moderate cliff slopes of 10°-15° because storm wind impinges on the cliffs at angles of 45° to 50° to the rim of the cliffs and is diverted to flow in a helical pattern parallel to the shoreline along the front slope of the cliffs. The diverted sand-moving wind is again deflected at the northern end of the cliffs, where its magnitude abates and it thus deposits sand that is being carried along the beach. The flow of the wind on the beach parallel to the foot of the cliff represents the effect of a non-homogeneous secondary wind. The wind is accelerated along the cliff, and as a result sand transport increases along the cliff. After a length of 150-200 m along the front slopes of the cliffs a state of equilibrium is achieved.
KeywordsWind Velocity Sand Dune Beach Sand Aeolian Sand Sand Transport
Unable to display preview. Download preview PDF.
- Ahlbrandt, T. S.: Textural parameters of eolian deposits. In: A study of global sand seas, (McKee E. D., ed.). Prof. Pap. U.S. Geol. Survey 1052, pp. 21–51, 1979.Google Scholar
- Bagnold, R. A.: The physics of blown sand and desert dunes. London: Methuen 1941.Google Scholar
- Chepil, W. S., Milne, R. A.: Comparative study of soil drifting in the field and in a wind tunnel. Sci. Agr. 19, 249–257 (1939).Google Scholar
- Folk, R. L., Ward, W. C.: Brazos River bar: a study in the significance of grain size parameters. J. Sed. Petrol. 27, 3–26 (1957).Google Scholar
- Goldsmith, V., Rosen, P., Gertner, Y.: Eolian sediments transport on the Israeli coast. Final Report, U.S.-Israel BSF, National Oceanographic Institute, Haifa, 1988.Google Scholar
- Hartmann, D.: Coastal sands of the southern and coastal part of the Mediterranean Coast of Israel-Reflection of dynamic sorting processes. Unpubl. Ph. D. dissertation, Aarhus University, 1988.Google Scholar
- Nir, Y.: Sedimentological aspects of the Israel and Sinai Mediterranean coasts. Geol. Survey of Israel, Report 39/88 (1989).Google Scholar
- Rosen, P. S.: An efficient, low cost, aeolian sampling system. Scient. Tech. Notes, Current Res. Part A, Geol. Surv. Canada, Pap. 78-1A, 531–532 (1979).Google Scholar
- Tsoar, H.: Trends in the development of sand dunes along the southeastern Mediterranean coast. Catena [Suppl.] 18, 51–60 (1990).Google Scholar
- Tsoar, H.: Grain size characteristics of wind ripples on a desert seif dune. Geogr. Res. Forum 10, 37–50 (1990).Google Scholar