Estimating Annual Onshore Aeolian Sand Supply from the Intertidal Beach Using an Aggregated-Scale Transport Formula

In this paper, we explore an approach for annual-scale transport prediction from the intertidal beach, in which we aggregate the surface conditions of the intertidal beach, in particular moisture content and roughness, and use hourly monitoring data of wind speed and wind direction. For our case study area (Egmond Beach, The Netherlands), we include Argus video imagery in our analysis to assess the occurrence of aeolian sand transport. With the approach described to determine a characteristic moisture content value for aeolian transport, we obtained surface moisture values of 1.2% to 3.2% for wind average and wind gust respectively, implying that we need a quite dry beach. This indicates that the main area for aeolian transport corresponds to the upper part of the intertidal source, most likely the region between mean high tide line and spring high tide line.

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Aeolian sand transport over gobi with different gravel coverages under limited sand supply: A mobile wind tunnel investigation

Aeolian Research ◽

10.1016/j.aeolia.2013.10.003 ◽

2013 ◽

Vol 11 ◽

pp. 67-74 ◽

Cited By ~ 21

Author(s):

Lihai Tan ◽

Weimin Zhang ◽

Jianjun Qu ◽

Kecun Zhang ◽

Zhishan An ◽

...

Keyword(s):

Wind Tunnel ◽

Sand Transport ◽

Aeolian Sand ◽

Aeolian Sand Transport ◽

Sand Supply

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A Review of the Effects of Surface Moisture Content on Aeolian Sand Transport

Desert Aeolian Processes ◽

10.1007/978-94-009-0067-7_13 ◽

1995 ◽

pp. 269-293 ◽

Cited By ~ 36

Author(s):

Steven L. Namikas ◽

Douglas J. Sherman

Keyword(s):

Moisture Content ◽

Sand Transport ◽

Aeolian Sand ◽

Surface Moisture ◽

Aeolian Sand Transport

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Discrete Element Simulation on Sand-Bed Collision Considering Surface Moisture Content

Processes ◽

10.3390/pr10010052 ◽

2021 ◽

Vol 10 (1) ◽

pp. 52

Author(s):

Hongchao Dun ◽

Peng Yue ◽

Ning Huang ◽

Jie Zhang

Keyword(s):

Moisture Content ◽

Discrete Element ◽

Coastal Areas ◽

Contact Forces ◽

Sand Transport ◽

Aeolian Sand ◽

Moisture Condition ◽

Surface Moisture ◽

Aeolian Sand Transport ◽

Long Time

The process of aeolian sand transport is an important mechanism leading to the formation and evolution of local landforms in coastal areas and desert lakes. For a long time, the role of surface moisture in incipient motion of sand grains by wind stress has been extensively studied but, in fact, sand-bed collision is the main mechanism in steady aeolian sand flow. At present, the lack of understanding of surface moisture content on sand-bed collision limits the application of aeolian sand transport models in wet coastal areas. In this paper, we adopt numerical simulations to discuss and analyze the effect of cohesive forces formed by surface moisture content on the sand-bed collision process based on discrete element method. High density contact forces appear with the surface moisture increasing, and form a closed structure around the edge of crater to resist the avulsion in horizontal direction. Under high moisture condition, even though the ejected sand grains saltate away from the surface, the tension forces will prevent from leaving. The ejected number trend with incident velocity shows some nonlinear characteristics due to the unequally distributed force chains and liquid bridges in the unsaturated sand bed surface.

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Using Video Monitoring to Test a Fetch-Based Aeolian Sand Transport Model

Journal of Marine Science and Engineering ◽

10.3390/jmse8020110 ◽

2020 ◽

Vol 8 (2) ◽

pp. 110 ◽

Cited By ~ 1

Author(s):

Pam Hage ◽

Gerben Ruessink ◽

Zilla van Aartrijk ◽

Jasper Donker

Keyword(s):

Wind Velocity ◽

Transport Model ◽

Transport Rate ◽

Beach Sand ◽

Sand Transport ◽

Winter Period ◽

Aeolian Sand ◽

Aeolian Transport ◽

Aeolian Sand Transport ◽

Strong Winds

Transport of beach sand to the foredune by wind is essential for dunes to grow. The aeolian sand transport rate is related to wind velocity, but wind-based models often overpredict this transport for narrow beaches (<100 m). To better predict aeolian sand transport, the fetch-based Aeolus model was developed. Here, we qualitatively test this model by comparing its transport-rate output to visual signs of aeolian transport on video imagery collected at Egmond aan Zee, the Netherlands, during a six-month winter period. The Aeolus model and the Argus images often agree on the timing of aeolian transport days, except when transport is small; that is not always visible on the Argus images. Consistent with the imagery (minimal signs of aeolian activity in strong winds), the Aeolus model sometimes predicts the actual transport to be smaller than the potential transport. This difference is largest when wind velocity is large, and its direction is cross-shore. Although transport limitations are not predicted to be common, the results suggest that their effect on the total transport in the study period was substantial. This indicates that the fetch distance should be taken into account when calculating aeolian transport for narrow beaches on longer timescales (>weeks).

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MANAGEMENT OF AEOLIAN SAND TRANSPORT ON A DIKE, DUNKIRK SEAPORT, FRANCE

Coastal Engineering Proceedings ◽

10.9753/icce.v33.sediment.91 ◽

2012 ◽

Vol 1 (33) ◽

pp. 91 ◽

Cited By ~ 2

Author(s):

Antoine Tresca ◽

Marie-Hélène Ruz ◽

Stéphane Raison ◽

Pascal Grégoire

Keyword(s):

Wind Speed ◽

Coastal Dunes ◽

Sand Transport ◽

Aeolian Sand ◽

Aeolian Transport ◽

Tidal Zone ◽

Aeolian Sand Transport ◽

Windblown Sand ◽

Wind Velocities ◽

Topographic Surveys

The shoreline of Dunkirk Seaport partly consists of a macrotidal beach oriented WSW-ENE backed by a 6 km long coated dike called “digue du Braek”. Aeolian sand transport was estimated on asphalt by means of sand traps. Also, time-averaged wind speed profiles were measured using cup anemometers under various wind velocities and directions along a transversal profile on the dike and the upper beach. High rates of sand transport enabled the setup of different kinds of experimental windbreaks on asphalt, in order to test potential dune formation on this kind of substrate. Under oblique onshore winds, it was regularly observed that amounts of sand captured in the traps placed on the dike were more important than those in traps placed on the upper beach. These results were related to sand sources: windblown sand captured on the dike originated from the coastal dunes developed at the dike toe, while sand trapped on the upper beach came from the tidal zone were aeolian transport is limited by complex intertidal bar-trough topography. It also appeared from the topographic surveys carried out on the windbreaks that although their location seemed to play a major role on the amount of sand captured, fences and synthetic fabrics deployed on sandy surfaces were also able to trap windblown sand on the seaport dike.

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