Storm Hydrographs Flashcards
What is river discharge? (+what is it measured in?)
The volume of water flowing in a river per second, it’s measure in cumecs (cubic meters per second)
What do storm/hydrographs show?
Hydrographs show the discharge at a certain point in a river
Storm Hydrographs show changes in river discharge during a storm
What is: The peak discharge? The lag time? The rising limb? The falling limb?
The highest discharge in the time period
The delay between peak rainfall and peak discharge
The inc. in discharge as rainwater flows into the river
The dec. in discharge as the river returns to the normal level
What causes lag time?
Rainwater doesn’t land directly in the river, it takes time to reach the channel by surface runoff or infiltration
Factors that inc. discharge are…
High rainfall Intense rainfall Impermeable rock Saturated soil Steep slopes Less vegetation
Factors that dec. discharge…
Low rainfall Light rainfall Permeable rock Dry unsaturated soil Gentle slopes More vegetation