Australie ; Capacité érosive ; Eastern Australia ; Energie cinétique ; Erosion des sols ; Erosion pluviale ; Goutte de pluie ; Géographie physique ; Pluie ; Précipitation
L'énergie cinétique des gouttes de pluie et, par suite, leur capacité érosive ne varient pratiquement plus dès lors que l'intensité des précipitations dépasse 100 mm/heure. - (JPB)
Seabed stress determinations using the inertial dissipation method and the turbulent kineticenergy method
Direct measurements of seabed stress are difficult, especially in field conditions. Several methods for estimating these stresses using current meter data are available. Two of these methods, the Inertial Dissipation Method and the Turbulent Kinetic
Energy Method, are described, and a Matlab program is used to analyse data from a wave-current environment.
In modelling interrill erosion caused by raindrops splashed on the soil surface, the parameters most frequently considered are the kineticenergy of the raindrops, the rain power and the rainfall intensity. This paper presents arguments supporting
the inclusion among these parameters of that part of the raindrops' kineticenergy that is expended to splash the soil downslope and introduces a theoretical mathematical equation for a dimensionless function of the kineticenergy distribution fd. This study
supports the division of raindrops into their upper and lower parts. The results demonstrated the benefit of using the dimensionless function of the kineticenergy distribution fd in empirical models of interrill erosion caused by raindrops.
The kinetic and available potential energy budget of a winter extratropical cyclone system
Amérique du Nord ; Atmosphère ; Bilan énergétique ; Climatologie ; Cyclone extratropical ; Date 1975 ; Dynamique de l'atmosphère ; Energie atmosphérique ; Evolution ; Géographie physique ; Hiver ; Libération de chaleur latente ; Perturbation ; Zone
Présentation du bilan d'énergie d'un système cyclonique extratropical d'une intensité assez exceptionnelle, ayant traversé l'Amérique du Nord du 9 au 11 janvier 1975. On insiste surtout sur le rôle de la libération de chaleur latente dans
Selective transport of sediment related to rainfall kineticenergy, plant cover-stoniness and clearing
Etude des relations entre le transport sélectif des sédiments, l'énergie cinétique de la pluie, la couverture végétale, la surface rocailleuse et la coupe de la végétation, dans des microparcelles expérimentales et des conditions semiarides
Interception, drop size distributions and rainfall kineticenergy in four colombian forest ecosystems
Les pluies interceptées représentent 11 à 20 % des pluies totales. La taille des gouttes a une distribution unimodale et bimodale pour l'égouttement. L'énergie cinétique de celui-ci est plus élevée que celle de la pluie à ciel ouvert (20-70 %) et
Comparison of blocking versus non-blocking using the local energetics of kineticenergy divided in vertical mean and sheared flows
Anticyclone ; Atmosphère ; Circulation atmosphérique ; Energie cinétique ; Modèle ; Pression atmosphérique ; Prévision météorologique ; Type de temps
The AA. compared the composite fields of typical cases for blocking and non-blocking, which where selected using objective thresholds. The results of this study demonstrate the obvious difference in mechanical energy flux between the blocking
and the non-blocking about 1.5 days after the onset time. It is suggested that the convergence of mechanical energy flux around the eastern flank of the ridge is the necessary condition for the blocking formation. In addition, there is a significant
convergence of mechanical energy flux around the upstream jet at 4 days before the onset. This may be the precursor signal of the formation of blocking.
The effect of a New Zealand beech forest canopy on the kineticenergy of water drops and on surface erosion
L'énergie cinétique des gouttes passant à travers le feuillage est toujours plus grande que celle des gouttes en champ ouvert. Lors d'une pluie de 36 h (51 mm) l'énergie cinétique totale de ces gouttes était 1,5 fois plus importante que les
The atmospheric energy budgets over North America, the North Atlantic and Europe
; Convergence ; Divergence ; Echange méridien ; Energie atmosphérique ; Energie cinétique ; Europe ; Géographie physique ; Hémisphère Nord ; Jet stream ; Système terre-atmosphère ; Variation diurne
Over the North American continent (the climatological jet entrance) there is generation and horizontal flux divergence of kineticenergy and adiabatic heating and divergence of temperature flux in the middle troposphere. The opposite holds
Author's concept is that relative relief means potential energy conceived in a physical sense. The value (theoretically calculated) for kineticenergy is referred to unit area und useful for the comparison of various catchments (in his example
Altitude ; Erosivity ; Island ; Kineticenergy ; Mauritius ; Precipitation ; Seasonal variation ; Soil erosion ; Tropical zone ; Volcanic rock ; Water erosion
Altitude ; Energie cinétique ; Erosion des sols ; Erosion hydrique ; Erosivité ; Ile ; Maurice ; Précipitation ; Roche volcanique ; Variation saisonnière ; Zone intertropicale
On Mauritius, erosive storm events are found to differ markedly between the coastal lowlands and the elevated interior with regard to the frequency, the total rainfall generated, the duration, total kineticenergy, and total erosivity of individual
events. However, mean kineticenergy, mean and maximum rainfall erosivity, and maximum intensities from individual erosive events do not show this distinct differentiation. Soil erosion risk occurs from storm-scale to synoptic-scale events, and extreme
Interrill erosion in soils with different land uses : The kineticenergy wetting effect on temporal particle size distribution
was used. Soil texture and aggregate stability were more important than overland flow in modifying the temporal PSD. Transport capacity appears to be diminished due to soil cover, making all predictions based on settling velocity ineffective. High kinetic
energy wetting (HKE) increases both the total and temporal sediment delivery rate (Di) values. Observed differences in Di were consequences not of particle size but of the number of particles released.
Measurement of soil splash erosion on an event-based scale under natural rainfall was carried out on a field spot. Kineticenergy of precipitation was calculated according to a model that incorporates horizontal terminal velocities of raindrops
induced by wind speed. A digital raingauge with a high output resolution was used to measure precipitation. Erositivity indexes were worked out based on the assumption that those minutes with the highest energy input in an event are decisive for soil
Rates of splash detachment from a sandy soil of the Cottenham series, subjected to a five minute design storm of 50 mm/h with a kineticenergy of 127 J/m and a median volum drop size of 3,2 mm supplied from a rotating-disc rainfall simulator
, are determined without a plant cover and with the cover of a single Brussels sprouts plant. The detachment rate was found rather surprisingly to be inversely related to the energy of the rainfall under the plant and positively related to the number of leaves.
Adsorption characteristics of modified sand for the removal of hexavalent chromium ions from aqueous solutions : Kinetic, thermodynamic and equilibrium studies
. The modified sand was characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDX) and FTIR. pHzpc of the raw and modified sands. The effect of important parameters such as initial concentration, contact time, adsorbent dosage, pH
and temperature on removal of Cr(VI) was investigated. Kinetics of removal process was studied by applying pseudo-first order and pseudo-second order models. The results obtained in this study show the modified sand to be a better adsorbent for removal of Cr(VI)
kineticenergy caused differences in soil detachability by overland flow. Furthermore, soil sampling in different periods of the year resulted in variations in soil detachment indicating a seasonal trend in soil detachability.
results are obtained when the product of rainfall kineticenergy and drop circumference is used or when rainfall detachment power is estimated as the 0.75 power of rainfall intensity.
Five simulated rainstorms, each with a different rainfall intensity pattern but all delivering the same total kineticenergy to the soil surface, were applied to three different soils in a laboratory flume. The three soils were : a clay loam