Water Cycle

• what are the main stages of the water cycle?

  - evaporation

  - condensation

  - precipitation

  - surface run off

  - transpiration through leaves
• what type of system is the hydrological cycle?

  closed system
• what type of system is the drainage basin?

  open system
• is the hydrological cycle global or local?

  global
• is the drainage basin global or local?

  local
• what are inputs?


  entering an open system
• what are outputs?


  exists the system
• what are stores?


  how water is held eg reservoirs
• what are flows?


  how water is transferred / moved from stores
• what are fluxes?


  rate of flow between stores
• what are processes?


  physical mechanisms that drive the rate of flow
• how much water is on the earth and in the atmosphere?

  1.4bn km3
• what are the main water stores?

  - oceans (97%)

  - rivers (0.01%)

  - ice caps / glaciers (1.9%)

  - groundwater (1.1%)

  - soil moisture (0.01%)

  - atmosphere (0.001%)
• what is the largest store?

  oceans (97%)
• what is the largest freshwater store?

  glaciers (ice) - 69%
• what do people extract drinking water from?

  - glaciers

  - groundwater

  - rivers
• what is the residence rate?

  how long water spends in a store
• what is the largest residence time?

  ice caps (15,000 years)
• what is fossil water?

  water held for thousands of years as groundwater (underground in rocks)
• what is the cryosphere?

  water frozen into ice or snow
• what drives the water cycle?

  - solar energy

  - gravitational potential energy
• what are the main processes in the water cycle?

  - evaporation

  - condensation

  - freezing

  - melting

  - precipitation

  - transpiration
• what is blue water?

  water stored in rivers, streams, lakes and groundwater in liquid form
• what is green water?

  water stored in the soil and vegetation
• what is a drainage basin?


  the area of land drained by a river and its tributaries
• what are the features of the drainage basin?

  - source

  - tributary

  - confluence

  - watershed

  - river channel

  - mouth (estuary)
• what is a tributary?

  a river or stream flowing into a larger river or lake
• what is confluence?


  the point where two rivers join
• what is evaporation?


  a liquid turns into a gas
• what is condensation?


  gas turns into a liquid
• what is precipitation?


  rain, snow, sleet, or hail that falls to the ground
• what is transpiration?


  evaporation of water from plant leaves
• what is freezing?


  liquid to solid
• what is melting?


  solid to liquid
• what is interception?


  water which is stopped by vegetation eg leaves
• what is throughfall?


  water dripping from leaves
• what is throughflow?


  water moving slowly downhill through the soil
• what is stem flow?


  water running down a twigs or branches
• what is infiltration?


  water on the ground surface enters the soil
• what is percolation?


  water moves vertically down through soil and rock