W&C: Key Words Flashcards
Key words in the introduction to systems
Cycle
An example of a continuous system.
System
A set of interrelated components working together towards some kind of process.
Helps to explain relationships.
Model
A way of simplifying or representing complex systems.
Elements
The parts or substances that make up a system.
Attributes
Characteristics of the elements that may be perceived and measured.
Relationships
Associations that occur between elements and attributes.
Boundary
The edge of a system.
Inputs
Elements entering a system.
Stores/components
Elements being stored in a system.
Flows/transfers
Elements moving around the system.
Outputs
Elements leaving the system.
Dynamic equilibrium
There is a balance between both inputs and outputs.
Open system
Where there are both inputs and outputs.
Energy and matter can be transferred across boundaries.
Closed system.
Where there are no inputs or outputs in a system.
Matter is confined to the system, but energy may enter and exit.
Positive feedback
The effects of an action are amplified by other knock on effects.
Negative feedback
The effects of a action are nullified by its knock on effects.
Isolated system
There are no interactions beyond its boundaries.
Cascading system
Made of a chain of open systems where the output from one system forms the input of another.
Atmosphere
The layer of gas between the Earth’s surface and space, held in place by gravity.
Lithosphere
The outermost part of the Earth.
It includes the crust and the upper parts of the mantle.
Hydrosphere.
Includes all the water on Earth.
- May be in liquid form, in solid form or in gaseous form.*
- It may be saline or fresh.*
Biosphere
Where living things are found.
All the living parts of the Earth.
Cryosphere
The parts of system where it is cold enough for water to freeze.
Magnitude
The assessment of the size or strength of something.
Precipitation
Water falling.
Can be in any form, such as rain, hail, sleet or snow.
Evaporation
The process by which liquid water changes into a gas.
This requires energy which is provided by the sun and aided by the wind.
Condensation
The process by which water vapour changes to liquid water.
Troposphere.
The lowest part of the atmosphere.
Where weather events occur.
ICTZ
Inter-Tropical Convergence Zone.
Dew point
The temperature at which water vapour turns into a liquid creating a cloud.
High pressure
When the air is descending and warming.
Low pressure
When warm air is rising, creating clouds and precipitation.
Orographic
The movement of water vapour over a mountain.
Prevailing wind
The most common wind direction.
Rain shadow
The side of the mountain that is dry due to the windward side receiving precipitation.
Ablation
When ice melts into water.
Accumulation
When liquid water freezes into ice.
Sublimation
When a solid turns immediately into a gas, without melting.
Deposition
When water vapour immediately freezes without turning into a liquid first.
Calving
When part of an ice sheet breaks off, creating an iceberg.
Ice sheets
A continental size mass of ice, covering at least 50,000 km², that is dome-shaped with flows of ice outward from the centre.
Ice caps
Thick layer of ice on land that are smaller than 50,000 km².
Glacier
A large mass of ice on land, moving downhill due to the influence of gravity.
Permafrost
Ground that remains at or below 0°C for at least two years.
Sea ice
The part of the Arctic and Antactic that freezes in the winter.
Latent heat
The amount of heat that is given out or taken in from the surroundings.
Water stress
The demand for water exceeds the amount of water available during a certain period, or when poor quality of water restricts its availability for human use.
When the annual supply of water per person is less than 1,700 m³.
Economic scarcity
Human and financial factors limit water use to less than 25% of river flows.
Water scarcity
When the annual supply of water per person is below 1000 m³.
