Unit 1C - River Landscapes in the UK - Rive discharge and flooding Flashcards
What is interception?
Water droplets collect on trees and plants
What is precipitation?
Rain, hail, sleet or snow
What is infiltration?
When surface water soaks into soil
Difference between permeable and impermeable?
Permeable - let’s water through
Impermeable - doesn’t let water through
What is surface runoff?
Water flowing on top of the ground
What is groundwater flow?
Water stored in porous rocks deep below the ground
What is throughflow?
Water flowing downhill through the soil
What is landscape?
An extensive area of land regarded as being visually and physically distinct
What is erosion?
Wearing away and removal of land by rivers, glaciers and wind, removing debris and providing input into river or coastal system
What is relief?
Height and shape of land
What are main causes of flooding?
Rainfall and snowmelt
What natural factors increase risk of flooding?
Relief, type of rock and prolonged and intensity of rainfall
What human factors increase risk of flooding?
Urbanisation, deforestation and agriculture
What is surface storage?
When water lies on ground as puddles or lakes
What is percolation?
Water moving downwards through soil into rocks below
What is transpiration?
Water vapour released by tress and plants
What is water table?
Upper level of saturated rock/soil
What is discharge of a river?
Amount of water in river at any given point and time, measured in cumecs (m³/s)
What does a hydrograph show?
How discharge at a certain point in a river changes over time in relation to rainfall
On a hydrograph, what is peak discharge?
Highest discharge in certain period of time
On a hydrograph, what is rising and falling limb?
Rising - increase in river discharge as rainwater flows into river
Falling - decrease in river discharge as river returns to its normal level
On a hydrograph, what is lag time?
Delay between peak rainfall and peak discharge
Difference between flashy and subdued hydrograph?
Flashy - rapid response to rainfall, ‘peaky’ graph and short lag time
Subdued - slower response to rainfall, ‘flatter’ graph and longer lag time
