The highly asymmetric near-ground outflow within the downburst has been analyzed within an axi-symmetric framework, by undertaking circumferential spatial averaging of the wind speed components, in order to explore whether the salient features of the outflow can be represented using the simpler models employed in wind engineering.
The explanation for the link, Marks suggests, is that thunderstorms pass over land containing rye grass, suck up rye pollen--a potent allergen--and then redirect it toward the ground in an outflow.
The downdraft hitting the ground creates an outflow boundary.
Huge linear swathes of scoured ground, known as outflow channels, cut across the surface in around 25 places.
Liquefaction and related phenomena, such as the outflow of ground water, sand boils, mud volcanism, and ground subsidence, are commonly observed after earthquakes (Manga and Wang 2007).
Radar data also reveal that the upstream portions of the channels lie near a lengthy system of fissures called Cerberus Fossae, the presumed source of the massive outflow of ground water thought to have carved Marte Vallis.
Following the first storm event, flow at the downstream locations was generated primarily through shallow subsurface flow and runoff whereas in the headwaters region – where a pond is located in the stream channel – shallow ground-water and pond outflow contributed to the flow.
Gustnadoes, short-lived vertical circulations near ground level, can be spawned by outflow boundaries.
It was ascertained from the application of void rate models in the hydro-thermal investigation of an underground coal fire that the correlation between heat production and ground surface temperature presents a linear function, while that between outflow velocity and fire source temperature has a negative-exponential-power relationship.
Precipitation, potential evapotranspiration, surface outflow, and water stored in the soil were evaluated for a 13-min period to determine the amount of ground water entering the bay.
