The global hydrological cycle Flashcards
Does Earths water ever change in quantity?
Never
Does earths water change its location?
Earths water constantly changes location and form as it moves through the GHC
What is the GHC (AKA the water cycle) ?
A closed system with inputs, flows, stores and outputs, no water arrives into or leaves from it
Where are the main water stores?
The ocean, ice, atmosphere, rivers and lakes, groundwater, permafrost, glaciers and biosphere (Plants and animals)
What are the main water fluxes? (flows/transfers)
Ocean evaporation, Ocean precipitation, Land precipitation, evaporation, transpiration, percolation and surface flow
What are the largest water stores?
The ocean and ice
How do you find a water budget?
Water inputs can be compared to outputs for any region on earth which gives the water budget or water balance
Since evaporation loss is greater than precipitation gain in the ocean why don’t they dry up?
The water budget for the ocean is balanced by surface flow from the land
Where does water reside for the longest time?
Groundwater where it can be stored for up to 10,000 years
Where does water reside for the shortest time?
Biospheric water which resides for up to 1 week
What gives proof that glaciers are very long term stores of water?
Otzi, a 5,300 year old frozen mummy found in the alps and other frozen relics
What happens if the water budget is not balanced?
Stores may become non-renewable
What is an example of an unbalanced water budget?
Cryosphere losses where ancient ice is melting due to climate change
Where is an example of the cryosphere being lost?
The Greenland Ice Sheet where 1000km^3 is being lost every 4 years
Why are ancient aquifers unbalanced?
Fossil water such as ancient aquifers are often under threat due to overexploitation
