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El recurso viento y su disponibilidad en las áreas geográficas de México

Mexico ; Natural resources ; Renewable energy ; Wind ; Wind energy ; Wind speed

Wind energy potential in the Cape coastal belt

Wind energy potential in the Cape coastal belt
Climatological records indicate that the coastal zone of the Cape Province experiences sustained wind speeds for energy conversion systems. Three particular sites are investigated. - (AJC)

A simple model for current speed in tidal channels

A simple model for current speed in tidal channels
Coastal environment ; Denmark ; Hydrodynamics ; Model ; Sea level ; Storm ; Tidal creek ; Tidal current ; Wind
This paper presents a simple non-distributed, PC-based model describing current speed in a tidal channel based on the continuity equation with tide gauge water level as the only time dependent input parameter. This model is tested in a tidal channel
in the Danish Wadden Sea. This type of model can be used to extend and/or complete time series of current speed in a particular tidal channel and to make quick estimates of the current speed, with a minimum of information and CPU consumption.

The effect of wind gusts, moisture content and fetch length on sand transport on a beach

The effect of wind gusts, moisture content and fetch length on sand transport on a beach
Aeolian features ; Coastal environment ; Denmark ; Jylland ; Sediment transport ; Soil moisture ; Wind speed
This paper reports on an analysis of instantaneous sediment transport in relation to wind gusts, moisture content and fetch length from a field study carried out at Skallingen, Denmark. Wind speeds were measured with cup anemometers
and dune sediment budgets : wind speed, surface moisture conditions.

A stochastic model for initial movement of sand grains by wind

A stochastic model for initial movement of sand grains by wind
Aeolian features ; Aeolian transport ; Model ; Stochastic model ; Threshold ; Wind ; Wind speed
A stochastic model for entrainment of sand grains by wind is presented through analysis of the forces exerted on a single spherical grain, coupled with fluctuations of wind velocity and the change in grain position on the surface, in order
to understand the probability of initial movement of sand grains by wind.

Simulation of daily total wind energy using a time-series model

Simulation of daily total wind energy using a time-series model
Climatic variability ; Forecast ; Interannual variability ; Model ; Simulation ; Statistics ; Time series ; United States of America ; Wind ; Wind speed
The focus of this research is the development, evaluation, and implementation of a mathematical/statistical time-series model to simulate daily total wind energy in the central United States. By modeling the annual cycle, sub-annual cycles
, autocorrelation, and random component of the time series, a concise representation of daily total wind energy is provided. The model can be used to create scenarios and probability distributions for wind energy that are conditional on time of year and persistence

The response of saltation to wind speed fluctuations

The response of saltation to wind speed fluctuations
Aeolian features ; Aeolian transport ; Coastal environment ; Experimentation ; Geophysics ; Germany ; Mecklenburg-West Pomerania ; Turbulence ; Wind speed
anemometer tower. Sediment transport measurements were obtained over 4 periods. The Wiener filter, a signal processing technique, is used to obtain a discrete transfer function that relates the horizontal wind speed and the non-intermittent sand transport

An increase in the frequency and intensity of uppertropospheric jet streaks over Europe in the period 1958-2003

Algorithm ; Europe ; Interannual variability ; Statistics ; Troposphere ; Wind ; Wind speed ; Years 1960-69 ; Years 1990-99
Mesoscale wind-speed maxime (jet streaks) in the upper toposphere over Europe in the period 1958-2003 were detected using a numerical algorithm. The number and wind speed in the central point of jet streaks and total number of days with at least one
were estimated and annual cycles and long-term variability to the statistics sought. An upward trend was noted for both the frequency and speed of jet streaks within the sector of the polar jet stream. - (BJ)

The variation in the concentration of airborne particulate matter with wind direction and wind speed in Denmark

The variation in the concentration of airborne particulate matter with wind direction and wind speed in Denmark

Interactions between airflow and valley topography with implications for aeolian sediment transport

Aeolian features ; Aeolian transport ; Arid area ; Desert ; Model ; Namibia ; Topography ; Valley ; Wind ; Wind speed
This paper investigates the impacts of dryland valley topography on wind speed and direction in order to understand better the effects of a valley on aeolian sediment dynamics. Anemometers and wind vanes were used to measure airflow characteristics

Aeolian processes across transverse dunes. I : modelling the air flow

Aeolian features ; Aeolian transport ; Dune ; Model ; Roughness ; Turbulence ; Wind ; Wind erosion ; Wind speed
This paper discusses a two-dimensional second-order closure model simulating air flow and turbulence across transverse dunes. Input parameters are upwind wind speed, topography of the dune ridge and surface roughness distribution over the ridge
. The most important output is the distribution of the friction velocity over the surface. The simulated wind speeds resemble patterns observed during field experiments. In order to obtain realistic predictions of friction velocity it was essential to include

Sediment flux and airflow on the stoss slope of a barchan dune

Aeolian features ; Aeolian transport ; Arid area ; Barchan ; California ; Dune ; Grain size distribution ; Sand ; Slope exposure ; United States of America ; Wind speed
Measurements of sediment flux on the windward slope of an isolated barchan using an array of 30 sand traps provide new data that can constrain models of dune dynamics. The data show that at low incident wind speeds, flux increases up the dune
exponentially, whereas at higher wind speeds the increase with distance approaches linearity. The wind profile measurements demonstrate that conventional wind profiles, derived from anemometry on dunes, do not measure the part of the boundary layer

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.

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

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

Impact-entrainment relationship in a saltating cloud

Aeolian features ; Aeolian transport ; Experimentation ; Impact ; Model ; Research technique ; Wind speed
(PDA) that employs phase Doppler technique in a wind tunnel. The primary objectives are to define the probability distribution of the speed and angle of impacting and entrained particles, and establish the relationship between impact and entrainment
with respect to their mean speed, angle and energy.

Analysis of the wind regime in context of dune geomorphology for the Kumtagh Desert, Northwest China

Analysis of the wind regime in context of dune geomorphology for the Kumtagh Desert, Northwest China
Aeolian features ; Arid area ; China ; Desert ; Dune ; Earth surface processes ; Wind speed ; Xinjiang
Based on field observations, the AA. analyzed the wind regime of China's Kumtagh Desert. The wind regime can be characterized based on both the mean wind speeds and the drift potential. The mean wind speed varied both spatially and temporally
of an intermediate-energy wind environment, and the index of directional variability is also intermediate. The diversity of local dune geomorphology should be associated with the complexity of the wind regime in each part of the region. However, the general
understanding of the desert's wind regime provided in this paper is not yet adequate to clarify the precise relationships between wind regime and dune geomorphology.

Aeolian mass transport near the saltation threshold

Aeolian features ; Aeolian transport ; Desert ; Experimentation ; Wind ; Wind speed
In order to study grain response to natural winds the AA. have made a desert study of intermittent saltation where the flow was recorded at high frequency within the saltation layer together with total mass transport. Using a conventional equation
relating mass flux to friction speed the AA. will discuss how mass transport relates to the velocity observations and how sensitive the prediction will be to the choice of variables.

Field experiments on physical weathering and wind erosion in an Antarctic cold desert

Field experiments on physical weathering and wind erosion in an Antarctic cold desert
Antarctica ; Cold area ; Cold desert ; Freezing ; Mountain ; Salt ; Surface temperature ; Weathering ; Wind erosion ; Wind speed
rockwalls, 2) disintegration of tuff blocks with or without saline solutions, and 3) abrasion of artificial walls by wind. Monitoring was also made of rock surface temperature and wind speed.

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