Water and Carbon Cycles

Question 1

What is a model in geography?

Answer 1

An idealised representation of reality.

Question 2

What is a system in geography?

Answer 2

A set of interrelated events or components working together.

Question 3

What is an isolated system?

Answer 3

A system in which there are no interactions between what is inside and outside of the system boundary. (no inputs/output of energy or matter)

Question 4

What is a closed system?

Answer 4

A system in which there is transfer of energy into and out of the system but no transfer of matter.

Question 5

What is an open system?

Answer 5

A system in which both energy and matter can transfer into and out of.

Question 6

What is a subsystem?

Answer 6

A component of a larger system, e.g. the earth is made up of 5 subsystems.

Question 7

What is the concept of dynamic equilibrium?

Answer 7

When there is a balance between inputs and outputs

Question 8

What is feedback?

Answer 8

What occurs when a change in one part of the system causes a change to another part.

Question 9

What is positive feedback?

Answer 9

A feedback in which there is a progressively greater change from the original condition of the system.

Question 10

What is negative feedback?

Answer 10

A feedback which keeps a system in its original condition.

Question 11

What are the earth’s five subsystems?

Answer 11

Atmosphere, hydrosphere, cryosphere, lithosphere, biosphere.

Question 12

What is evapotranspiration?

Answer 12

The process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by transpiration from plants.

Question 13

What is condensation with reference to clouds?

Answer 13

A physical process where water vapour becomes water. It happens when air cools and water molecules condense onto nuclei like dust or smoke.

Question 14

When do clouds form?

Answer 14

• When the air is saturated as it has cooled below the dew point or evaporation means the air has reached its maximum holding capacity.
• Condensation nuclei like smoke and dust are present

Question 15

What causes precipitation?

Answer 15

• Air temperature is reduced to a dew point so water drops.

- Volume of the air increases as it rises and expands but there is no addition of heat (adiabatic cooling)

Question 16

What is accumulation in the cryosphere?

Answer 16

Inputs into the glacial system due to snowfall.

Question 17

What is ablation in the cryosphere?

Answer 17

The output of a glacial system due to melting.

Question 18

What is sublimation in the cryosphere?

Answer 18

Ice changing directly into water vapour.

Question 19

What is a drainage basin?

Answer 19

An area of land, drained by a river and its tributaries.

Question 20

What is a watershed?

Answer 20

A watershed describes an area of land that contains a common set of streams and rivers that all drain into a single larger body of water.

Question 21

What is run-off?

Answer 21

The output of water from the drainage basin system as it moves across the land surface either as overland flow or channel flow.

Question 22

What is interception?

Answer 22

When precipitation does not reach the soil, but is instead intercepted by the leaves, branches of plants and the forest floor.

Question 23

What are the main types of water storage?

Answer 23

• Interception storage
• Surface storage
• Soil water storage
• Ground water storage
• Channel storage
• Vegetation storage

Question 24

What was the last ice age and when was it?

Answer 24

It was the Pleistocene epoch and happened 2,580,000 to 11,700 years ago

Question 25

What is stemflow?

Answer 25

Water that flows down the stems of plants and trees.

Question 26

What is infiltration?

Answer 26

Water that soaks into the soil.

Question 27

What is overland flow?

Answer 27

Rainfall flowing over the ground surface either because the soil is saturated or because rainfall is exceeding the soil infiltration capacity.

Question 28

What is through-fall?

Answer 28

Water moving from vegetation to the ground

Question 29

What is percolation?

Answer 29

Downward and lateral movement of water into underground stores.

Question 30

What is groundwater flow?

Answer 30

Downward and lateral movement of water within saturated rock.

Question 31

What is an aquifer?

Answer 31

An underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials (gravel, sand, or silt).

Question 32

What is a positive water balance?

Answer 32

Where precipitation exceeds evapotranspiration.

Question 33

What is a negative water balance?

Answer 33

Where evapotranspiration exceeds precipitation.

Question 34

What is river discharge?

Answer 34

This is the total volume of water flowing through a channel at any given point and is measured in cubic metres per second (cumecs).

Question 35

What does a “flashy” hydrograph look like?

Answer 35

It has a short lag time, high peak, steep rising and falling limbs.

Question 36

What does a “subdued” hydrograph look like?

Answer 36

It has a long lag time, low peak, gently rising and falling limb.

Question 37

What physical factors affect the response of a river to a storm event?

Answer 37

Drainage basin shape (circular/elongated), relief (steep/shallow), vegetation, geology (permeable/impermeable).

Question 38

What human factors affect the response of a river to a storm event?

Answer 38

Water abstraction, afforestation, urban growth.

Question 39

What are carbon fluxes?

Answer 39

The amount of carbon exchanged between Earth’s carbon pools.

Question 40

What are carbon pools?

Answer 40

Reservoirs of carbon that have the capacity to both take in and release carbon.

Question 41

What is an ecosystem?

Answer 41

A community of living organisms, their relationships between each other and the environment.

Question 42

What is photosynthesis?

Answer 42

A process used by plants and other organisms to convert light energy into chemical energy

Question 43

What is carbon sequestration?

Answer 43

a natural or artificial process by which carbon dioxide is removed from the atmosphere.

Question 44

How do wildfires affect the carbon cycle?

Answer 44

Dense areas of carbon-storing plants are burnt down, causing carbon dioxide to enter the atmosphere. Soil is then exposed, releasing more carbon from decaying plant matter. Increased CO2 concentrations lead to global warming.

Question 45

How does volcanic activity affect the carbon cycle?

Answer 45

Volcanic eruptions release lots of sulphur dioxide into the upper atmosphere, reducing the amount of incoming solar radiation, leading to global cooling, though this can be countered by greenhouse gases also produced.

Question 46

How do farming practices affect the carbon cycle?

Answer 46

Ploughing introduces air into the soil causing decomposition to accelerate and releasing lots of carbon into the atmosphere. Livestock release methane by product of digestion and equipment like tractors can release CO2.

Question 47

What is a carbon budget?

Answer 47

A list of all the carbon pools with an estimate of their size and a summary of all the fluxes that constitute inputs and outputs.

Question 48

How has fossil fuel combustion affected the carbon cycle on land?

Answer 48

• The amount of carbon plants take up has increased meaning, plants have grown more (carbon fertilisation)
• Wildfires could become more frequent and of higher magnitude.

Question 49

How has fossil fuel combustion affected the carbon cycle in the oceans?

Answer 49

• Ocean acidification due to carbonic acid being created form carbon dioxide in the atmosphere affecting coral reefs
• Phytoplankton can grow better in cooler oceans so this could reduce their ability to absorb carbon.
• Reducing sea ice, reduces the earth’s albedo as water is more absorbent of solar radiation than reflective.
• Sea levels have risen (eusostatic change)

Question 50

How has fossil fuel combustion affected the carbon cycle in the atmosphere?

Answer 50

The earth will warm due to the greenhouse effect.