The flood hydrograph Flashcards
What is discharge?
the volume of water passing through a river at a moment of time
What is discharge measured in?
cumecs (cubic metres per second
What is a flood hydrograph?
a graph to show the discharge of a river
What is the basin size like in a flashy hydrograph?
small which leads to a rapid water transfer
What is the basin size like in a low hydrograph?
large which leads to slower water transfer
What type of hydrograph has a short lag time and high peak?
Flashy hydrograph
What type of hydrograph has a low peak?
low hydrograph
Define lag time.
the time between peak rainfall and peak discharge
What is the drainage basin like in a flashy hydrograph?
has a high density which speeds up water transfer
What is the drainage basin like in a low hydrograph?
has a low density which slows water transfer
What is the rock type like in a flashy hydrograph?
impermeable which leads to rapid overland flow
What is the rock type like in a low hydrograph?
permeable rocks which leads to slow transfer by groundwater flow
What is the land use like in a flashy hydrograph?
Urbanisation
What is the land use like in a low hydrograph?
forests which slow down the water transfer because of interception
What is the relief like in a flashy hydrograph?
steep slopes
What is the relief like in a low hydrograph?
gentle slopes
What is the soil water like in a flashy hydrograph?
saturated soil
What is the soil water like in a low hydrograph?
dry soil which soaks up the water and slows down its transfer
What is the rainfall intensity like in a flashy hydrograph?
heavy rain
What is the rainfall intensity like in a low hydrograph?
light rain
