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Directional characteristics of potentially damaging wind gusts in the southeast United States

Directional characteristics of potentially damaging wind gusts in the southeast United States
Climatology ; Damage ; Forecast ; Natural hazards ; United States of America ; Wind ; Wind speed
In this study, this wind gust data is analyzed from a network of 20 weather stations in the southeastern United States. From this analysis, the AA. develop a short-term climatology that summarizes regional variations in the prevailing directions
and speeds of high winds. The results will provide a preliminary guide to the zones around trees that are most threatened by blowover from high winds.

Linear dune trends and wind directions in the northern Cape Province, South Africa

Linear dune trends and wind directions in the northern Cape Province, South Africa
Cape Province ; Dunes ; Eolian features ; South Africa ; Wind
Four linear dune fields in the northern Cape were examined and their trends related to prevailing wind patterns. Evidence is shown for the retention of direction from previous wind patterns, as well as the influence of the coriolis deflection

Vent fort et très fort et types de circulation atmosphérique en Pologne

Atmospheric circulation ; Poland ; Wind
Strong and very strong winds were recorded at 16 stations during the period 1956-1965. Poland's climate is characterised by rather small average frequency of strong and very strong wind. Nevertheless geographical and dynamical factors influence
the frequency of wind. Tha aim of this study is to estimate the influence of changes of the atmospheric circulation on the frequency of strong and very strong wind. - (DG)

Morfologické vplyvy na zmeny vetra na tatranskych vrcholech. (The morphological effects on changes of the Wind in the High Tatras)

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

Aerosol deposition off the South African West Coast by Berg winds

Aerosol deposition off the South African West Coast by Berg winds
Aerosol ; Atmospheric dynamics ; Coastal environment ; South Africa ; Wind
Berg winds off the west coast of southern Africa are associated with wintertime subcontinental and ridging anticyclone. Although not frequent, Berg winds are considered the most important atmospheric agents of aerosol transport and deposition off

Birds, wind and the making of wind power landscapes in Aude, Southern France

Birds, wind and the making of wind power landscapes in Aude, Southern France
Aeolian features ; Aude ; Bird ; Environmental management ; France ; Impact ; Landscape ; Languedoc-Roussillon ; Man-environment relations ; Wind energy
Landscape and birds are an important cause of blocking wind power projects. This paper investigates in the South of France the question of whether birds and wind power can be part of a same landscape and what type of landscape this could compose
. The AA. focuse on the attachments that animals or landscape might develop or entice humans to develop. They show that the process by which such a wind power landscape is composed engages birds into successive translations, which ultimately translate bird
intelligence in composing with the wind into a quality of the landscape. As a result, such a landscape emerges from a net of relations and has a quality which is not necessarily visually readable: it is accountable to the entities which have been brought

Jutranji termični veter v Barkovljah pri Trstu

Climate ; Forecast ; Italy ; Local climate ; Trieste ; Wind
Geographical position of Slovenia is the main reason that applicable winds are quite infrequent, therefore the knowledge about specific local winds is of a great significance. The research objective was to determine and evaluate conditions
for the development of amplified morning thermic wind in the gulf in front of Barcola village near Trieste, analyzing the general weather conditions, local wind and air temperature conditions and the influence of coastal relief. The article shows that beside air
temperature difference between coastal region and the Karst plateau, steep coastal relief with explicit valleys and narrows, the final wind parameters are influenced also by general air-mass movement in broader the Karst plateau. The comparison of actual wind
conditions with wind forecasts of meteorological model ALADIN returns the outlook of criteria for reliable forecasts of amplified morning thermic wind - (IKR)

The influence of rainfall on transport of beach sand by wind

The influence of rainfall on transport of beach sand by wind
Aeolian features ; Aeolian transport ; Beach ; Coastal environment ; Dune ; Experimentation ; Netherlands (The) ; Precipitation ; Sand ; Soil moisture ; Splash ; Wind ; Wind speed
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

Raindrop-induced and wind-driven soil particle transport

Raindrop-induced and wind-driven soil particle transport
Belgium ; Cultivated land ; Experimentation ; Sediment transport ; Slope gradient ; Soil erosion ; Splash ; Statistics ; Wind ; Wind speed
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

Influence of shelter on soil sorting by wind erosion. A case study

Influence of shelter on soil sorting by wind erosion. A case study
Agricultural practice ; Agropedology ; Denmark ; Jylland ; Soil erosion ; Soil properties ; Soil science ; Wind ; Wind erosion
Textural analyses were conducted in order to quantify the soil status in two nearby fields with 80 m and 200 m spacing of shelter hedges with unequal wind exposure and within the fields themselves. Chosen soil status indicators are the content
of silt+clay, coarse particles and organic matter. The aim of this paper is to provide a quantification and a spatial description of possible differences in soil status that can be linked to wind erosion.

A conceptual model of wind erosion of soil surfaces by saltating particles

A conceptual model of wind erosion of soil surfaces by saltating particles
Aeolian features ; Erosion rate ; Experimentation ; Model ; Soil erosion ; United Kingdom ; Wind ; Wind erosion
This paper presents a conceptual model of wind erosion by saltating grains in which the erosion rate is determined by the strength of the surface and the energy delivered to the surface by the saltating grains. Methods are presented
for the measurement of both distributions and consequent loss of material from the bed. It is concluded that saltating sand grains can rupture weak crusts under even moderate wind conditions, and that the rate of erosion will depend on the shape of the distribution

Wind erosion in agricultural soils : an example of limited supply of particles available for erosion

Wind erosion in agricultural soils : an example of limited supply of particles available for erosion
Agricultural practice ; Agropedology ; Aragón ; Arid area ; Semi-arid area ; Soil ; Soil erosion ; Spain ; Wind ; Wind erosion
Due to particular soil and climate conditions and inappropriate agricultural practices, Central Aragón (NE Spain) is a semiarid region prone to land degradation by wind erosion. A field study was conducted during the summer 1995 to provide a first
quantification of wind erosion in agricultural soils of this region. This paper focuses on the mouldboard ploughing experiment, analysing in detail changes in vertical dust flux with time in response to changes in soil surface erodibility.

Simulation of the effect of wind speedup in the formation of transverse dune fields

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.

Wind tunnel evaluation of a wedge-shaped aeolian sediment trap

Wind tunnel evaluation of a wedge-shaped aeolian sediment trap
Aeolian features ; Aeolian transport ; Dust ; Eolian deflation ; Experimentation ; Research technique ; Sand ; Wind erosion
A detailed set of tests in a wind tunnel investigated the characteristics of flow and sampling efficiency of a low cost sediment trap that can be used in wind tunnels and field applications. Results indicate that this trap, and others that have wide
side profiles, are very sensitive to incident wind angle.

Physical principle of wind erosion on sandy land surface in southern Beijing

Physical principle of wind erosion on sandy land surface in southern Beijing
Aeolian features ; Aeolian transport ; Beijing ; China ; Land use ; Wind erosion ; Wind speed
activities and measures controlling wind erosion in Daxing District of Beijing. Different land use types result in various degrees of coarse component. There is a significant exponential relation between sediment transport concentration and wind velocity.

Wind erosion of blanket peat during a short period of surface desiccation (North Pennines, Northern England)

Wind erosion of blanket peat during a short period of surface desiccation (North Pennines, Northern England)
Aeolian features ; Climatic data ; England ; Peat ; Precipitation ; Soil erosion ; United Kingdom ; Wind erosion ; Wind speed
The aim of this research is to report the first direct measurements of dry blow process of wind erosion on bare blanket peat in an upland environment. Data presented in this paper were collected as part of a longer-term project investigating wind

Wind erosion research in China : past, present and future

Wind erosion research in China : past, present and future
Aeolian deflation ; Aeolian features ; Arid area ; Bibliography ; China ; Desertification ; Erosion control ; Model ; Semi-arid area ; Wind erosion
Wind erosion is one of the most important processes associated with land degradation and desertification in the arid, semi-arid and portions of the subhumid regions of China. In this paper, an outline of the main research results from China related
to wind erosion are presented, and some prospects and suggestions intended to address some of the problems in both research and control practices of wind erosion in China are put forward.

Sand detachment by wind-driven raindrops

Sand detachment by wind-driven raindrops
Belgium ; Experimentation ; Impact ; Rainfall simulation ; Soil erosion ; Splash ; Water erosion ; Wind
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.

The flux profile of a blowing sand cloud : a wind tunnel investigation

The flux profile of a blowing sand cloud : a wind tunnel investigation
Aeolian features ; Aeolian transport ; China ; Desert ; Experimentation ; Grain size distribution ; Model ; Wind speed
The AA. report the wind tunnel results of systematic tests of the flux profiles of different sized sands at different free-stream wind velocities. The results reveal that within the 60-cm near-surface layer, the decay of blown sand flux with height
can be expressed by an exponential function. The AA. define the physical significance of the parameters in flux profiles and their relationship to grain size and wind velocity. They also discuss the average saltation height of blown sand

Vertical distribution of wind-blown sand flux in the surface layer, Taklamakan Desert, Central Asia

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 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
. 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
distribution and predicting the total sediment transport quantity of wind-blown sand flux near the ground surface.

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