W&C - The Water Cycle: Local Scale Flashcards
What are the inputs in the water cycle?
Precipitation
What are the 3 types of rainfall?
Frontal, relief, convectional
Describe frontal rainfall
- When two bodies of are at different temperatures meet, the warmer air rises over the cool air because it is less dense and therefore lighter
- This warm air rises and then condenses at higher altitudes, where it falls back down as rain
Describe convectional rainfall
- sun causes temperatures to increase
- warm air rises, condenses at higher altitudes and falls back down as rain
Describe relief rainfall
- warm air is forced upwards by a barrier such as mountains, where it condenses at the higher altitudes and falls as rain
What are the outputs in the water cycle?
- evapotranspiration
- streamflow
What is transpiration?
- the movement of water through a plant
- ends with the water being evaporated
Name and explain the flows in the water cycle
Infiltration = water moving into the soil from the ground surface
Percolation = water moving from the soil into porous rock
Throughflow = water flowing through the soil
Groundwater flow = water moving through the porous rock
Surface runoff = water flowing over the surface of the ground
Streamflow = water moving through designated channels
Stemflow = water moving down a plant as a result of interception
What are the stores in the water cycle?
Groundwater storage = water stored in the pores of rocks
Soil storage = water stored in the soil
Channel storage = water stored short term in river channels
Surface storage = water stored in bodies of water on the surface of the ground
Interception = water stored by plants before reaching the ground
What is the equation for the water balance?
Precipitation = total runoff + evapotranspiration +/- change in storage
Define the water balance
The balance between the inputs, outputs and processes within a drainage basin
What is the soil water budget?
The annual balance between inputs and outputs in the water cycle and its impact on the soil water storage
Describe the winter soil water budget
- soil moisture recharge
- water surplus
- minimum evapotranspiration
- increase in infiltration and percolation as precipitation refills water stores
Describe the summer soil water budget
- evapotranspiration exceeds precipitation
- soil water utilisation
- minimal precipitation
- can lead to a water deficit if there is a long summer
Name and explain the physical factors affecting the water cycle on a local scale
Storm events = large bursts of rainfall saturate the ground quickly
- doesn’t replenish water stores as effectively as prolonged rainfall because it does not allow for percolation to occur as much, instead increases surface runoff
Seasonal changes
- summer = low precipitation, high evapotranspiration
- winter = high precipitation, minimal evapotranspiration, less interception (plants have no leaves)