Distribution + Size of Stores

what is a open system?

• energy and matter can enter and leave

• e.g river basin

what is a closed system?

• matter is conserved but energy can enter/leave

• e.g global water cycle

what is a flow?

• movement of water between stores

what is a store?

• a place where water is held

what is the hydrosphere?

how much water does it hold?

• all water on earth e.g oceans, lakes

• ~1.332B km³ (97%)

what is the cryosphere?

how much water does it hold?

• frozen water in glaciers, ice caps, etc

• ~24M km³ (3%)

how is water stored in groundwater?

how much water does it hold?

• in underground aquifers

• ~23M km³ (0.6%)

how is water stored in the atmosphere?

how much water does it hold?

• water vapour and clouds

• 12,900 km³

input involved in moving water: precipitation

• rain, snow, sleet falling from atmosphere on Earth’s surface

• water vapour condensing and falling due to gravity

input involved in moving water: snowmelt

• melting of snow and ice, esp in spring/summer

• can cause flooding if rapid

output involved in moving water: evapotranspiration

• evaporation: liquid water → vapour

• transpiration: water released from plant leaves

• controlled by temp, wind + veg cover