EQ1- Water Balance and River Regimes Flashcards
precipitation=
discharge+evaporation +/- changes in stores
river regime
-the annual variation in discharge of a river at a particular location. most of river flow isn’t from immediate precipitation but is from groundwater between periods of rain
Factors affecting the characteristic of a river’s regime include:
▪ Channel capacity of the river
▪ Area and relief of the drainage basin
▪ Volume, pattern and intensity of precipitation
▪ Climate
▪ Geology of the soil (affecting the input of groundwater)
▪ Anthropogenic (human) activities, such as building dams or terracing the land.
storm hydrographs
-represent variation in discharge within a short period of time
-Before a storm begins, the main supply of water to the river is through groundwater or base flow.
-However, as a storm develops, infiltration and surface runoff will increase which causes a greater throughflow.
storm hydrograph
rising limb
-the increase of river discharge, not necessarily instantaneously after precipitation
storm hydrogaph
peak flow
The maximum discharge, delayed after maximum precipitation has occurred.
storm hydrpgraph
lag time
The time delay between peak rainfall and peak discharge
storm hydrograph
falling limb
-As the storm precipitation levels decrease, discharge will in turn decrease over time
storm hydrograph
base flow
Eventually, the discharge returns to its normal level
simple regime
where river experiences a period of seasonality with high discharge followed by low discharge.
EG river rhone w/ a temperate climate where summer snow melt occurs
complex regime
where larger rivers cross several diff relief + climatic zones, therefore experineces diff climate events
EG Ganges which flows 2,500 km from western himalayans to bay of bengal
spatial variations
