The Carbon and Water Cycle

Question 1

How Features of Drainage Basins might affect Discharge of the River

Answer 1

-Reservoir = holds water, reducing discharge during periods of high rainfall
-Tributaries = larger the discharge ratio, larger sudden increase in discharge, more permanent changes (physical) downstream
-Agricultural = infiltration/percolation through rock/water flows to river channels by groundwater through flow, increasing river discharge
-Urban = impermeable, decreased infiltration, increased surface runoff, increasing discharge

Question 2

Significant Impacts Droughts have on Stores and Transfers in the Water Cycle

Answer 2

-Reduction in water stores (rivers, lakes)
-Loss of vegetation affects processes (transpiration, interception, infiltration)
-Groundwater flow more important (long term)
-Heat and dry air causes initial high rates of evapotranspiration. This declines as water dries up and trees transpire less
-Soils dry out - soil water store now reduced

Question 3

Drainage Basin

Answer 3

(Or catchment area) is the area that supplies a river with its supply of water.

An open system (has external interaction)

Question 4

Human Factors Affecting Change in the Water Cycle

Answer 4

Climate change

Water Abstraction

Farming practices

Land use change

Question 5

Bradshaw Model

Answer 5

Increase as you move down the river:
-Discharge
-Depth
-Width
-Velocity

Question 6

What is a Cloud?

Answer 6

Visible mass of water droplets or ice crystals suspended in the atmosphere.

Cloud formation is the result of air in the lower layers of Earth’s atmosphere becoming saturated due to either or both of 2 processes:
-Cooling of air and increase of water vapour
-When cloud droplets grow they can eventually fall as rain

Question 7

Cryosphere

Answer 7

-Contains about 1.8% of water but 70% of fresh water
-Albedo effect - interactions between snow and ice cover and the radiation budget
-Strong positive feedback mechanisms - particularly sensitive to climate change

Question 8

Within the boundaries of a system there are 3 different properties…

Answer 8

Elements: things that make up the system. These may be atoms, molecules, raindrops, plants, animals, etc

Attributes: characteristics of the element that are perceived or measured e.g. size, colour, volume, temperature, etc

Relationships: the associations or connections between elements and attributes

Question 9

Isolated, Closed and Open Systems

Answer 9

Isolated system: no interactions with anything outside the system boundary.

Closed system: energy transferred into and out of the system. All matter is enclosed.

Open system: matter and energy can be transferred from the system into the surrounding environment.

Question 10

Fusion, Freezing, Vaporisation and Condensation

Answer 10

Fusion: the substance changes from a solid to a liquid

Freezing: the substance changes from a liquid to a solid

Vaporisation: the substance changes from a liquid to a vapour

Condensation: the substance changes from a vapour to a liquid

Question 11

Inter-Tropical Convergence Zone (ITCZ)

Answer 11

At the equator, high temperature result in high rates of evaporation. The warm air rises, cools and condenses to form towering banks of cloud and heavy rainfall in a low pressure zone known as the ITCZ

Moves North/South with the seasons

Question 12

Global Circulation System

Answer 12

1 Air cools and sinks, creating a belt of high pressure and a cold dry climate (polar cell)
2 60 degrees North and South, cold polar air mixes with warmer air and rises, creating a belt of low pressure(ferrel cell)
3 Cool air sinks (high) and becomes warmer and drier
4 Warm air rises (low) and cools. Clouds form and release precipitation, move to higher latitudes (equator)
5 Sun’s heat is concentrated (hadley cell)
6 Sun’s heat spread out (ferrel-polar cell)

Question 13

Frontal Rainfall

Answer 13

UK experiences a lot as we have depressions that bring lots of cold and warm air together. Occurs when:
-2 air masses meet, 1 warm, 1 cold
-Lighter, less dense, warm air forced over cold air
-Causes warm air to cool and begin to condense
-As warm air forced to rise, further condensation occurs and rain formed
-Produces variety of clouds, brings moderate-heavy rainfall

Question 14

Relief Rainfall (Orographic Rainfall)

Answer 14

Very common in west coast of UK as prevailing wind comes from that direction. Occurs when:
-Prevailing winds pick up moisture from sea
-Moist air reaches coast and forced over mountains
-Forces air to cool and condense, forming clouds
-Air continues over mountains, drops moisture as relief rain
-Once over top, drops over other side (and warming). Greater ability to carry out water moisture so little rain on far side of mountain (rain shadow)

Question 15

Convectional Rainfall

Answer 15

Common where ground heated by hot sun (Tropics, Costa Rica, Brazil, Madagascar, Indonesia), South East of UK in summer. Occurs when:
-Surface of Earth heated by sun, heating air above
-As it rises, cools, begins to condensate
-Further rising and cooling - large amounts of condensation (rain formed)
-Convection tends to produce cumulonimbus-nimbus clouds, produce heavy rain and possible thunder and lightning

Question 16

Positive and Negative Water Balance

Answer 16

If precipitation exceeds runoff and evapotranspiration, there will be a positive water balance (amount of water stored increasing)

If runoff and evapotranspiration exceeds precipitation, there will be a negative water balance (amount of water stored decreasing)

Question 17

Soil Moisture Budget

Answer 17

Change in amount of water stored in the soil throughout the year.

Main factors:
-Precipitation
-Potential evaporation = amount of evapotranspiration that could occur if sufficient water available
-Linked to temperature - increased temperature = increased evapotranspiration
-Often temperature is greater than amount of water available