Geoscience Reference
In-Depth Information
Between Storms
During Storms
Figure 1.3
The processes involved in one perceptual model of hillslope hydrology (after Beven, 1991a).
affected by the topography and vegetation cover. Much deeper snow will often be found in the lee of
ridges, a feature that has been well documented in the Reynolds Creek catchment in Idaho and elsewhere
(see Bathurst and Cooley, 1996 and Section 5.3). There can also be feedback effects, in that deeper snow
cover might lead to more water being available to the vegetation leading to greater growth and, in the
case of trees, to greater trapping of snow drifting in the wind.
Once the rain or snowmelt water has reached the ground, it will start to infiltrate the soil surface,
except on impermeable areas of bare rock, areas of completely frozen soil, or some man-made surfaces
where
surface runoff
will start almost immediately. The rate and amount of infiltration will be limited
by the rainfall intensity and the
infiltration capacity
of the soil. Where the input rate exceeds the infil-
tration capacity of the soil,
infiltration excess overland flow
will be generated. Soils tend to be locally
