hydrograph Flashcards
What is a hydrograph?
A hydrograph is a graph that shows the response of a river to a rain event in its drainage basin
What is peak discharge
Peak discharge is the point at which the river reaches its highest level.
What is peak rainfall
The highest amount of rainfall (most rain falls)
What is lag time
The time difference between peak discharge and peak rainfall.
What is the rising limb
Rising limb is the time when the river discharge is increasing.
What is the falling limb
The Falling limb is the time when the river discharge is falling.
What is base flow
Base flow is the normal flow of the river before the rain event.
Type of slope affects the line on a hydrograph. How would the steep line be and how would the gentle line be?
If it is steep, the water will fall very quickly into the water. This would have a very fast rising limb and then a falling limb and has a short lag time. Flashy hydrograph
If it is a gentle slope, it would have a longer lag time before it then falls. Non flashy hydrograph
Soil type hydrograph. How would the impermeable line be and how would the permeable line be?
If there is permeable soil, there would be rapid infiltration and little overland flow, resulting in a less steep rising limb. This is a non-flashy hydrograph
If it is impermeable, there would be a steeper rising limb and short lag time as there would be lots of overland flow. This is flashy hydrograph
