In this study, sediment transport rates by raindrop-impacted shallow flow were measured under wind-driven rain. By comparing the results from windward and leeward slopes, the AA aimed to clarify the effects of wind velocity and direction
on the transport process. The study was conducted in a wind tunnel rainfall simulator facility at Ghent University, Belgium.
The effect of a change of wind direction on the orientation (and some other morphometric characteristics) or aeolian dust ripples is investigated. Ripple formation is simulated in a wind tunnel on surfaces that are already characterized
by a previously established rippling. The effect of a wind rotation 45 degrees, 90 degrees, and 180 degrees is examined.
Morfologické vplyvy na zmeny vetra na tatranskych vrcholech. (The morphological effects on changes of the Wind in the High Tatras)
The disturbances of the wind through geomorphological influences are studied according to measurements of the wind velocity and wind directions in two selected meteorological stations in the High Tatras. The results are statistically evaluated
Wind erosion of residue waste. Part I. Using the wind profile to characterise wind erosion
Aeolian features ; Agropedology ; Australia ; Erodibility ; Field experiment ; Sedimentology ; Western Australia ; Wind erosion
A portable wind tunnel is used to assess the erodibility of prepared surfaces of residue waste. The data are extensive and include wind profiles, collections of saltation and suspension material as well as particle sizing by elutriation. Still
, the data show no definitive information on the effects of treatment. There are difficulties in the use of the gradient of the log profile and the intercept as measures of the shear stress and the scale.
Interannual variability of wind speed and wind power at five tall-tower sites in Minnesota (1996-2001)
Interannual variability ; Methodology ; Minnesota ; United States of America ; Wind ; Wind energy ; Wind speed ; Years 1990-99
patterns of variability. They use the standard deviation (computed from mean hourly data) as a measure of within-year variability because squared differences emphasize the effects of the long tails of the wind speed and wind power distributions.
The AA. use wind speed measurements from 1996-2001 at 70 m above ground (a typical wind turbine height) to investigate interannual variability in wind speed and wind power at 5 sites in Minnesota, and to determine whether the sites have similar
Simulation of the effect of wind speedup in the formation of transverse dune fields
Aeolian features ; Dune ; Earth surface processes ; Model ; Simulation ; Wind speed
The AA. analyse Werner's dune-field simulation model for the uni-directional wind regime leading to the evolution of transverse dunes. Following this, they introduce 2 revisions to the Werner model, which lead to dunes that more closely resemble
those in nature. The first revision incorporates wind structure over a dune, and the second considers the wind speedup and the equilibrium dune shape.
The aim of this study is to investigate the physical effects of rock fragment eccentricity on the dust deposition mechanism. This was examined in a wind tunnel. All data in this study refer to intial dust deposition (not accumulation), since only
wind velocities below the dust deflation threshold were tested.
The effect of single vegetation elements on wind speed and sediment transport in the Sahelian Zone of Burkina Faso
Arid area ; Burkina ; Sahel ; Scrub ; Sediment transport ; Soil erosion ; Tree ; Vegetation ; Wind erosion ; Wind speed
The aim of this study was to determine the effects of a single tree and shrub on wind speed and sediment transport in the Sahelian zone of Burkina Faso. First an overview will be given of the effects of sparse vegetation and single vegetation
elements on wind speed and sediment transport as known from the literature. Subsequently, results of experimental work that was done in the north of Burkina Faso on the pattern of wind speed and sediment transport around single trees and shrubs
Wind-blown particles as weathering agents? An Antarctic example
Observations from Taylor Valley suggest that the wedging effect of sand particles, packed by powerful winds into cracks in rocks, may act as a weathering mechanism. Discussion.
The effect of the dry bulk density, time and the presence of roughness elements at the surface on the wind erodibility of a dry dune sand (D=230-250m) were evaluated in a laboratory study.
Grain-size analysis of surface material under wind erosion using the effective surface concept
Aeolian features ; Aeolian transport ; Concept ; Experimentation ; Grain size distribution ; Methodology ; Roughness ; Wind erosion
This paper deals with the temporal variation in the grain size of surface material using an analytical method based on the effective surface concept. This method is applied to data collected in 2 series of wind tunnel experiments. The results
Crust strength : a wind tunnel study of the effect of impact by saltating particles on cohesive soil surfaces
Aeolian features ; Aeolian transport ; Duricrust ; Experimentation ; Soil ; Soil properties ; Wind erosion
A wind tunnel study examined the effect of distributions of saltating particles on sediment surfaces which were characterized by distributions of their tensile strength. The sediments consisted of varying proportions of large sand-sized particles
This study was conducted in a wind tunnel rainfall simulator facility at Ghent University, Belgium. The AA present experimental results directly obtained on the effect of horizontal wind velocity on sand detachment from splash cups
, with the objective of providing a better insight into the detachment process under wind-driven raindrops.
This paper deals with the effect of rainfall on the process of wind erosion of beach sands and presents results from both field and wind tunnel experiments. The study was carried out using fine, well sorted beached sand of one particular beach
. The influence of the surface moisture content on the initiation of wind erosion and on the vertical distribution of transported sand particles was studied in a wind tunnel. Moisture significantly increased threshold wind velocities for the initiation of sediment
A wind tunnel study under wind-driven rains was conducted at Ghent University, Belgium, to determine the combined effect of rain and wind on the rainsplash transport process. Transport rates were measured by trapping the splashed particles at set
distances in the upslope and downslope directions, respectively, for windward and leeward slopes. Rainsplash transport under wind-driven rains was adequately described by relating the transport rate to the rain impact pressure and wind shear velocity by log
Aeolian features ; Aeolian transport ; Avalanche ; California ; Mass movement ; Model ; Roughness ; Soil properties ; United States of America ; Wind erosion ; Wind speed
The increase of soil mass flux with distance downwind, the fetch effect for wind erosion, has been observed and reported on since 1939. The model proposed incorporates 3 mechanisms: 1) the avalanching mechanism in which one particle moving downwind
would dislodge one or more particles upon impact with the surface; 2) the aerodynamic feedback effect in which the aerodynamic roughness height is increased by saltation of particles; 3) the soil resistance mechanism, which is largely an expression
Vertical distribution of wind-blown sand flux in the surface layer, Taklamakan Desert, Central Asia
Aeolian features ; Aeolian transport ; Arid area ; China ; Desert ; Dune ; Experimentation ; Sand ; Wind speed ; Xinjiang
. The objectives were: to determine the effect of wind velocity on the distribution pattern of wind-blown sand flow; to examine the properties of the discontinuous function of the transport rate with height; and to develop an equation for expressing the vertical
The vertical distribution of the wind-blown sand flux in a 40 cm low layer above the ground surface was investigated through laboratory wind-tunnel tests and field measurements on the mobile dune surface during sand storms in the Taklamakan Desert
distribution and predicting the total sediment transport quantity of wind-blown sand flux near the ground surface.
Experimental study of wind directional variability in the vicinity of a model valley
Aeolian features ; Aeolian transport ; Aerosol ; Atmospheric pollution ; Experimentation ; Modelling ; Topography ; Valley ; Wind ; Wind speed
This paper reports the results of a preliminary study examining the effects of valley presence on airflow direction and focuses on valleys situated in areas of low relief. Wind tunnel experiments are used to visualise near-surface airflow over
Regional wind fields and dunefield migration, southern Brazil
Aeolian features ; Aeolian transport ; Beach ; Brazil ; Coastal environment ; Dune ; Grain size distribution ; Local wind ; Remote sensing ; Santa Catarina ; Topography
This paper outlines an initial study examining the factors possibly responsible for a marked variation in dunefield migration trends. These factors include grain size variations, topographic effects on local winds, shoreline orientation
, and regional wind field changes. Two beaches with opposite migration trends, Joaquina on Florianopolis and Pinheira on the adjacent mainland are examined in detail.