Field Measurement of Aeolian Sand Flux over a Sand Dune Slope Junaidi Keiko UDO, Shota MITSUSHIO, JUNAIDI, Shin-ichi AOKI, Shigeru KATO and Akira MANO

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Field Measurement of Aeolian Sand Flux over a Sand Dune Slope Junaidi Keiko UDO, Shota MITSUSHIO, JUNAIDI, Shin-ichi AOKI, Shigeru KATO and Akira MANO This study conducted field observations in terms

over a sand dune slope. The Charnock constant, related to wind shear on the sand bed surface, calculated from the wind velocity data on the slope had a larger value over a flat.

1 Field Measurement of Aeolian Sand Flux over a Sand Dune Slope Junaidi Keiko UDO, Shota MITSUSHIO, JUNAIDI, Shin-ichi AOKI, Shigeru KATO and Akira MANO This study conducted field observations in terms of the number of blown sand impacts and wind velocity for two hours on 21 February 2009 at an open ocean beach in Japan, in order to investigate characteristics of the aeolian sand transport flux over a sand dune slope. The Charnock constant, related to wind shear on the sand bed surface, calculated from the wind velocity data on the slope had a larger value over a flat. Furthermore, the aeolian flux on the slope tended to be larger than that on the flat. Knowledge of the Charnock constant and the aeolian flux on the flat and slope was obtained from the field measurements, which will become a great help for further investigation of the aeolian sand transport mechanisms Davidson-Arnott Jackson 1996 Sensit Stockton Gillette 1990 Safire Baas 2004 UD Udo 2008 UD-101 UD m Foot F CrestC

Junaidi 2009 0.04m z 0.04m 1Hz 1 z 0.3m1.0m 1 11:23 13:38 2 154 3 FootFCrest C F 4 Crest 3Foot Crest 0.3 0.35mm Foot 0.33mm Crest 0.35mm 3. 1 Foot Crest Crest z 0.3m 1.

2 Junaidi m z 0.04m 1Hz 1 z 0.3m1.0m 1 11:23 13: FootFCrest C F 4 Crest 3Foot Crest mm Foot 0.33mm Crest 0.35mm 3. 1 Foot Crest Crest z 0.3m 1.0m Foot z 0.3m 1 3 z 0.3m 1.0m 1u mean z 0.04m 1 n5 6 u * z 0.3m Foot Crestz 1.0m Foot Crest Foot Crest Foot 3.0cm Crest 2.5cm 1 1.5cm 2 Udo z 0.3m 1.0mu mean u mean u * z 0.04m n

3 7 z 0.3m1.0m u mean C0.05 C0.16 C0.29 c 0 = u mean n 2 1 κ 0.4 u * z z 0 z 0 z 0s 2 Charnock 1955 Owen 1964 Raupach 1991 Sherman Farrell 2008 g 9.81ms -2 c 0 Charnock constantraupach Sherman Farrell 2008 c 0 c Raupach Crest Footz 0.3m1.0m u mean 7 c 0 = Crest Foot c Crest Foot6 1 z 0 u 2 * /2g Crest Foot c u mean u * 3 n 1 1 n mean 8 z 0.3m n mean Crest n mean Foot z 1.0m Foot Crest n mean u * n mean n mean u * Udo G ρ (u * u *t ) u * 0.5ms -1 Crest Foot u * 0.5ms -1 n mean 1951 Crest u * ms -1 Crest c 0 2u * 5 u * 3

4 8 z 0.3m 1.0mu mean n mean 9 u * n mean KW Eq Foot u * z 0.3m 1.0m0ms -1 5 u * z 0.3m 1.0m 3 3 z 1.0mz 0.9m Udo 2008 n mean n mean 0 3ms ms -1 10D mm 0.1mm Bagnold z 1.0mz 0.9m 4 Foot-Crest FootCrestn 5 26 nn F n C 10 dt 0s n F n C n F dtn C dt 0s R Rdt 10 Foot 12:23 12:281n mean n F dtcrestn mean n C

5 n C Foot Crest n F n C R 3 6s ms -1 z 0.04m 2009 Foot Crest 3 6s Foot Crest 80m 10 16ms Charnock constant Charnock constant z 0.04mn mean z 0.3m n mean z 1.0m z 0.3m 1.0m u mean u * n mean u * 0.5ms -1 u * 0.5ms -1 FootCrestn n F n C dt 3 6s n F 2009 B2 65 pp No. 5 pp pp Baas, A.C.W. (2004) : Evaluation of saltation flux impact responders (Safires) for measuring instantaneous aeolian sand transport intensity. Geomorphology, 59, pp Bagnold R.A. (1941) : The Physics of Blown Sand and Desert Dunes, Methuen, London, 265p Charnock, H. (1955): Wind stress on a water surface, The Quarterly Journal of the Royal Meteorological Society, vol. 81, pp Davidson-Arnott, R.G.D., Yang, Y., Ollerhead, J., Hesp, P.A., and Walker, I.J. (2008) : The effects of surface moisture on aeolian sediment transport threshold and mass flux on a beach. Earth Surface Processes and Landforms, 33, pp Jackson, D.W.T. (1996) A new, instantaneous aeolian sand trap for field use. Sedimentology, 43, pp Junaidi 2009 B2 65 pp Owen, P. R. (1964) : Saltation of uniform grains in air, Journal of Fluid Mechanics, vol. 20, pp Raupach, M.R. (1991) : Saltation layers, vegetation canopies and roughness lengths, Acta mechanica, [Supple] 1, pp Sherman, D.J. and Farrell, E.J. (2008) : Aerodynamic roughness lengths over movable beds: Comparison of wind tunnel and field data, Journal of Geophysical Research, 113, F02S08, doi: /2007jf Stockton, P.H. and Gillette, D.A. (1990) : Field measurement of the sheltering effect of vegetation on erodible land surfaces, Land degradation & rehabilitation, vol. 2, pp Udo, K., Kuriyama, Y., and Jackson, D.W.T. (2008) : Observations of wind-blown sand under various meteorological conditions. Journal of Geophysical Research, 113, F04008, doi: /2007JF

Field Observations of Aeolian Sand Transport Rate Using a Piezoelectric Ceramic Sensor This study conducted field observations in terms of the number

Field Observations of Aeolian Sand Transport Rate Using a Piezoelectric Ceramic Sensor This study conducted field observations in terms of the number of blown sand impacts and wind velocity in the period