Geography T1 - River regimes + Hydrographs

What is river channel?

the part of the river that holds the water (the confine of a river)

What is channel/drainage network?

system of surface and underground channels that collects and transports precipitation falling on the drainage basin.

what is drainage density?

The relative density (mass) of natural drainage channels in a given area. It is obtained by dividing the total length of stream channels by the total area of the drainage basin.
Lower drainage density means a lower chance of flooding.
This can be shown using a hydrograph.

What is a hydrograph?

is a diagram that shows how rainfall affects the discharge of a river.

What is time lag or lag time?

time taken for the rainwater to reach the river

what is river regime?

seasonal variation in the discharge

what is base flow?

the ‘normal’ discharge of a river

what is discharge?

the amount of water carried by a river at any given time. This is measured in cumecs, that is the cubic metres of water per second moving past a particular point along the river’s course.

Example of a hydrograph

What does a storm hydrograph record?

charging discharge of a river after a passing rainstorm