Physical Causes Of Flooding Flashcards
What are the stages of the water cycle?
Precipitation - Evaporation Interception Transpiration - Evap Surface Storage Surface Run-off - Infiltration. River - Soil Moisture Throughflow - Percolation - Groundwater. Groundwater flow
What are the input stages?
Precipitation.
What are the Output stages?
Evaporation (x2)
Transpiration
River carrying water to lake or sea
What are the storage stages?
Interception
Surface storage
Soil moisture
Groundwater
What are the flow/transfer stages?
Infiltration Percolation Surface run off Throughflow Groundwater flow
What is Infiltration?
Water sinking into soil/rock from the ground surface.
What is percolation?
Water seeping deeper below the surface.
What is throughflow?
Water flowing through the soil layer parallel to the surface.
What is Groundwater flow?
Water flowing through the rock layer parallel to the surface.
What is a water table?
Current upper level of saturated rock/soil where no more water can be absorbed.
What increases flood risk (physical)?
- Bands of depressions passing over the UK at frequent intervals
- Sudden bursts of heavy rain
- Prolonged light rainfall
- Sudden snow melt
How can geology and relief increase flood risk?
- impermeable rock increases flood risk
- thin soils with lack of vegetation
- Compacted impermeable clay soil
- Steep slopes increase flood risk
- Low lying flat flood plains increase flood risk as there is not enough gradient to remove the water.
What is groundwater?
Water stored in the rock.
What is interception?
Water being prevented from reaching the surface by trees or grass.
What is transpiration?
Water lost through pores in vegetation.
