The water cycle Flashcards
(21 cards)
What is the percentage of fresh water in this world?
2.5%
Definition Of hydrological cycle
the continuous movement of water on, above and below Earth’s surface’
What is a rock that stores water called?
Aquifer
What is sublimation?
When solid water turns into water vapour
What is deposition?
When water vapour turns into solid water
What is evaporation?
Evaporation is the process of turning from a liquid to a gas. Evaporation occurs when energy from the sun hits the surface of the water/land and causes liquid to change from liquid to gas.
Factors of evaporation
Rates of evaporation depend on:
Amount of solar energy
Availability of water
Humidity of the air - The more humid the air the closer to saturation point the air is so less evaporation will occur
Temperature of the air – Warmer air can hold more water than cold air.
What is condensation
Condensation is the conversion of a vapor or gas into a liquid.
Condensation occurs because air is either;
Cooled or
There is an increase in pressure.
As air cools or if there is a increase in pressure it is able to hold less water vapor.
The dew point is the temperature at which water vapour in the air turns into liquid water.
How do clouds form?
As the air reaches the dew point and there’s enough condensation nuclei in the atmosphere air drops collide to form larger drops and cools and condenses to form clouds.
How is convectional rainfall formed.
1) Solar radiation emits energy which causes the evaporation of water. The water vapour then rises where it condenses at the cloud base. This creates thunderstorms or cumulonimbus clouds.
How is orographic rainfall formed?
Humid air hits the ground and rises due to the relief of the land.It then cools and condenses to form clouds at the cloud base and rains.Further down the air will have less moisture and will be drier which causes a rainshadow.
What is frontal rainfall.
In the UK we also get Frontal Rainfall.
Here, warmer air meets colder air at areas that we call FRONTS.
At a cold front, cold dense air pushes warmer air up to create large cumulonimbus clouds
At a warm front, warm air rises more gently over colder air creating nimbostratus and higher cirrus clouds
Since a lot of our weather comes from the WEST, this can work together with RELIEF or OROGRAPHIC rainfall
Crysopheric processes
Ice forms from the compression of falling snow. As layer upon layer of snow is added it can exert a pressure on the snow at the base, compressing that snow and forcing air out of it. This will slowly form a denser substance called Névé and eventually ice. Melting and refreezing of previously fallen snow can also assist in this process.
What is accumilation and ablation?
The build up of ice mass
and loss of ice mass
Cryosphere water changes?
More condensation
more freezing
more deposition
An example of climate change that causes the process of change in the water cycle?
Glacial and interglacial periods
glacial is cold = 100,000
interglacial = 10,000
How does interception and infiltration affect a drainage basin?
explain…
What are the 5 LOCAL CHANGES in the water cycle in a drainage basin?
Deforestation - Removal of trees reduces interception and infiltration. Surface runoff increases
Urbanisation - Increased impermeable surfaces reduce infiltration and increase surface runoff.
farming - Compaction of soil reduce infiltration. Irrigation increase surface stores
seasonal - Frozen ground in the winter reduces infiltration. Deciduous trees lose their leaves decrease interception
storms - Increase magnitude of stores
What are the flows along a hill slope?
Infiltration
peroculation
ground water flow
through flow
overland flow
Stream flow
Outline the flows within the water cycle operating on a hill slope.
Surface runoff occurs when water runs directly on the ground. This may be due to saturated soil or impermable surfaces.
Infiltration is when water moves into the soil and moves down into impermable rock or ground water sources.
Throughflow occurs under the force of gravity when water moves downslope in the soil into a water source.
Groundwater flow is the movement of water through permeable rock under the force of gravity and is slow.
Explain the concept of dynamic equilibrium in relation to the water cycle?
Dynamic Equilibrium is where there is a balance between inputs and outputs in the water cycle. Globally it is an closed system as no matter (water) enters or leaves the system (1).
Locally the drainage basin is an open system input is the precipitation and output of the system is evaporation, transpiration and river output (1).
Theses input/outputs can change over time as global weather patterns change or extreme weather events like a storm hazard but will over time the disruption to dynamic equilibrium return to equilibrium as the river regime output will increase(1).
Dynamic equilibrium can be changed by human activity such as dams or other modification to the drainage basin(1).
