1.2.1 Introduction to the water cycle Flashcards
All water on the planet is described as part of the …
Hyrosphere
What are the following four stores that make up the hydrosphere?
- Oceanic water
- Cryospheric water
- Terrestrial water
- Atmospheric water
Oceanic water
- The largest store of water on earth.
- Accounts for 97% of the earth’s water in total.
- Oceans cover 72% of the Earth’s surface.
- Broken up into oceans and seas.
- Oceanic water is salty with a falling pH.
Cryospheric water
- Water that is stored on earth in solid form (ice).
- Stores of cryospheric water includes sea ice, permafrost, ice sheets, ice caps and glaciers.
Terrestrial water
Freshwater that is on the earth, including:
o Surface water – Water on the Earth’s surface, e.g. in rivers and lakes.
o Biological water – Water stored within biomass (in plants and animals).
o Groundwater
o Soil water
Atmospheric water
- Can be held in all three states – solid , liquid or gas (water vapour).
- Water held in the atmospheric acts as a greenhouse gas and is used to control the Earth’s temperature.
Accessibility of water
- Water must be physically and economically accessible.
- Only 0.01% of all the water of the planet is accessible to us.
- Accessible water is mainly only available from rivers, ice/permafrost, swamps, marshes, soil moisture, the atmosphere, and lakes.
Change in the magnitude of water stores
Water can change between solid, liquid and gaseous forms. For water to boil or melt, it has to gain energy. For water to condense or freeze, it has to lose energy.
Blue water
All parts of the water cycle that are visible.
Green water
Any parts of the water cycle that are invisible (to the human eye).
Fossil water
Water is so deep that is unusable for humans.
Latent heat
The heat required to convert a solid into a liquid or vapour, or a liquid into a vapour without a change in temperature.
Residence time
The average length of time each water molecules are stored in each store.
Residence time for:
- Oceans
- Atmosphere
- Groundwater
- Oceans = 3,600 years
- Atmosphere = 10 days
- Groundwater = Up to 10,000 years.
Soil water budget
The annual balance between precipitation, evapotranspiration and runoff.