Journal ArticleDOI
Relationships between deflation and near surface wind velocity in a coastal dune blowout
Reads0
Chats0
TLDR
In this paper, detailed field measurements were made of the degree of surface level change in a blowout, situated in the coastal dune area of Meijendel, The Netherlands.Abstract:
Detailed field measurements were made of the degree of surface level change in a blowout, situated in the coastal dune area of Meijendel, The Netherlands. A formula was established to express the erosivity of the wind for the corresponding 34 measurement intervals, over a period of about 3 years. Having established, for 12 wind sectors, the relationship between wind velocity at the nearest standard weather station and at five locations in the blowout, correlations were derived between the deflation rate in the blowout and the wind erosivity using standard hourly wind data.
The winter season, although the most windy, is by far the least effective season: the threshold shear wind velocity is disproportionally increased because the moisture content of the surface sand is high. The soil moisture conditions are described as a function of the daily precipitation and evaporation rate. The two most relevant upper and lower threshold shear wind velocities are determined empirically. During the summer season, deflation rate is even higher than indicated by the net surface level change because deflation is partly compensated by deposition of sand transported by rainwash from the blowout margin.
With regard to spatial variation in the deflation rate within the blowout, it appears that locations with relatively high velocities coincide with higher deflation rates. However, the spatial variation is commonly less than is expected from the horizontal wind velocity distribution. In view of this the role of wind direction, blowout morphology and algal coverage of the soil in the deflation rate is discussed.read more
Citations
More filters
Journal ArticleDOI
Foredunes and blowouts: initiation, geomorphology and dynamics
TL;DR: A review of the initiation, dynamics, geomorphology and evolution of incipient foredunes, established foredune, and blowout is given in this paper, where the authors present a new model of the evolutionary paths at various possible time scales.
Journal ArticleDOI
Forecasting the response of Earth's surface to future climatic and land use changes: A review of methods and research needs
Jon D. Pelletier,A. Brad Murray,Jennifer L. Pierce,Paul R. Bierman,David D. Breshears,Benjamin T. Crosby,Michael A. Ellis,Efi Foufoula-Georgiou,Arjun M. Heimsath,Chris Houser,Nicholas Lancaster,Marco Marani,Marco Marani,Dorothy J. Merritts,Laura J. Moore,Joel L. Pederson,Michael J. Poulos,Tammy M. Rittenour,Joel C. Rowland,Peter Ruggiero,Dylan J. Ward,Andrew D. Wickert,Elowyn M. Yager +22 more
TL;DR: The authors assesses the state-of-the-art tools and data that are being used or could be used to forecast changes in the state of Earth's surface as a result of likely future C&LUC.
Book ChapterDOI
7 – Disturbance Processes and Dynamics in Coastal Dunes
TL;DR: In this paper, it has been demonstrated that the predominant factors that have a significant impact on the dynamics of coastal dune vegetation can be divided into two groups: environmental gradients and recurring disturbances.
Journal ArticleDOI
High resolution measured and modelled three-dimensional airflow over a coastal bowl blowout
TL;DR: In this article, the authors measured and modeled the heterogeneity of wind flow over a bowl blowout on the Belmullet Peninsula, Ireland using ultrasonic three-dimensional anemometry (measuring at 50 Hz) and 3D computational fluid dynamic (CFD) modelling.
Journal Article
The development of coastal dunes and their vegetation in Finland
TL;DR: In this article, the development of coastal dune fields in the area from Virolahti to Hailuoto is studied from the literature, maps, aerial photographs and vegetation transect analyses.
References
More filters
Journal ArticleDOI
Principles of Environmental Physics
TL;DR: In this paper, the second edition of the Second edition, the authors present a list of symbolic symbols for the field of environmental physical sciences, including the following: 1.GAS LAWS Pressure, volume and temperature Specific heats Lapse rate Water and water vapour Other gases 3. TRANSPORT LAWS General transfer equation Molecular transfer processes Diffusion coefficients Radiation laws 4. RADI ENVIRONMENT Solar radiation Terrestrial radiation Net radiation 5. MICROCLIMATOLOGY OF RADIATION (i) Interception Direct solar radiation Diffuse radiation Radiation in
Book
The Physics of Blown Sand and Desert Dunes
TL;DR: The physics of blown sand and desert dunes, The physics of windblown sand and sand dunes, this paper, and the physics of dunes in the Middle East and Africa.
Journal ArticleDOI
The flow of cohesionless grains in fluids
TL;DR: In this article, it was shown that if the bed is composed entirely of potentially mobile grains a stress-equilibrium relation at the bed surface can be defined whereby the magnitude of a certain "bed load" of grains in transit over unit bed area is given in terms of the applied tangential stress.
Journal ArticleDOI
Measurements of sand transport by wind on a natural beach
J. N. Svasek,J. H. J. Terwindt +1 more
TL;DR: The measured critical shear velocity U*c at the beginning of sand movement on a clean dry beach agrees very well with that predicted by Bagnold's formula as mentioned in this paper, provided the shear stress velocity U * > 0·D4 m/s.
Related Papers (5)
The development of blowouts in `de blink', a coastal dune area near Noordwijkerhout, The Netherlands
The development of dune blowouts, as measured with erosion pins and sequential air photos
P.D. Jungerius,F. van der Meulen +1 more