The Water Cycle Flashcards
Precipitation
The falling of atmospheric water vapour, for example, in the form of rain, snow, hail and sleet.
Condensation
The conversion of gas to droplets of water
Evaporation
The conversion of liquid to vapour
Transpiration
The evaporation of water through the stomata in a plant’s leaves
Evapotranspiration
The combined total moisture transferred from the Earth to the atmosphere, through evaporation and transpiration
Throughflow
Water moving horizontally through the soil, due to gravity
Infiltration
The process by which water enters and moves through the soil
Percolation
The process by which water enters and moves through the rock
Residency time
The amount of time something is held in a store.
What are the longest stores?
Deep oceans and ice.
What are the shortest stores?
Clouds + the surface of puddles, lakes etc., because lots of evaporation occurs
Albedo Effect
The refraction of the solar radiation by ice
Is the Albedo Effect an example of positive or negative feedback?
Positive feedback
Explain how the Albedo Effect is an example of positive feedback
- ice reflects solar radiation
- therefore, it stays cold
- so ice grows
- and there is more of an Albedo Effect
- so it continues to stay cold
This is an example of positive feedback, because an initial change is bringing about additional change in the same direction, further distorting the system and enhancing the Albedo Effect (?)
What is the difference between positive and negative feedback?
With positive feedback, an initial change will bring about an additional change in the same direction, whereas, with negative feedback, an initial change will bring about an additional change in the opposite direction. Positive feedback further distorts systems, whereas, negative feedback stops or reverses processes, meaning that the system becomes more balanced again.
Give some negative feedback examples
- dam
- mass movement
- deforestation, e.g., it prevents things like throughfall
- wildfires, e.g., it stops the trees in the Water Cycle from being able to do the transfers
How much of the Earth is covered in water?
3/4
How long have the oceans been here for?
Almost 4 billion years (our planet was born about 4.5 billion years ago)
What percentage of Earth’s water is in the ocean?
97%
What percentage of the Earth’s water is freshwater?
3%
How much of the Earth’s freshwater is accessible?
3% of the Earth’s water is freshwater. Within this, about 2% is locked in glaciers, ice caps and groundwater. There is only about 1% of water on Earth that is accessible and usable by humans.
System
A set of interrelated components working together towards some kind of process.
Elements
Things making up a system
Attributes
Characteristics of the elements
Relationships
How the elements and their attributes work together to carry out a process.
Isolated systems
No input or output of energy or matter
Closed systems
These have inputs and outputs of energy, but not matter.
Open systems
These have inputs and outputs of energy and matter
Dynamic Equilibrium
The inputs and outputs are balanced
What are the Earth’s 4 major subsystems?
- atmosphere
- lithosphere
- hydrosphere
- biosphere
Give an example of positive feedback, with regards to CO2 levels in the atmosphere
- global temperature rise
- leads to increased oceanic temperatures
- which leads to dissolved CO2 released by warmer oceans
- resulting in more CO2 in the atmosphere
- leading to a global temperature rise
Give an example of negative feedback, with regards to CO2 levels in the atmosphere
- increased use of fossil fuels
- leads to an increase in atmospheric CO2
- so there is more plant growth
- which reduces atmospheric CO2
- we continue to use fossil fuels more
How big is the Antarctic ice sheet?
The Antarctic ice sheet extends almost 14 million km squared
Effect of rising temperatures on permafrost
As climate warms, the permafrost has begun to melt. This melting releases large amounts of carbon dioxide and methane.
Approximately what percentage of the planet’s surface do oceans cover?
Approximately 72%
What is the main ecosystem in the Arctic?
Wetlands
Why do polar areas tend to be quite dry?
Because cold air can’t hold as much water as warm air
Sublimation
The change in state from solid to gas
Deposition
The change in state from gas to solid
Evaporation
The change in state from liquid to gas
Ice melt
Ablation
Ice gain
Accumulation
When do interglacial periods occur?
When ice melt (ablation) exceeds ice gain (accumulation)
Accumulation
Ice build up year on year
How long does it take for the weight of the snow to squeeze out all the air, forming ice?
About 20 years
Ice is a ……
Preserver
How often does ablation happen?
Seasonally
After around how many years does the Earth change from being in a glacial period to being in an interglacial period?
Roughly every 100,000 years
What are the 3 main reasons for natural climate change?
- sunspots
- volcanic eruptions
- The Milankovitch Cycles
The more sunspots you have ……
The hotter the sun
What can volcanic eruptions do to global temperature?
They can cool it down
The Milankovitch Cycles
When we move from being on a more circular orbit to a more elliptical orbit - we will have periods closer to the sun and periods further from the sun. This happens about every 100,000 years
What do The Milankovitch Cycles coincide with?
The glacial and interglacial periods
Convectional rainfall
When the sun heats the earth’s surface and causes water to evaporate, changing it to water vapour. When air is hot, it rises, cools and condenses to form rain.
Frontal rainfall
Occurs when a warm front meets a cold front. The moisture in the warm air condenses as it cools, which causes clouds and rain.
Relief rainfall
Occurs when warm moist air from the Atlantic Ocean rises up over mountains
Jet streams
A ribbon of very strong winds. The stronger the temperature gradient, the stronger the jet.
What are the 3 main types of rainfall?
- relief
- frontal
- convectional