The water cycle Flashcards
Explain the global distribution and size of the lithosphere
- Outermost part of Earth including crust and upper parts of the mantle (30% freshwater as groundwater)
- Divided into tectonic plates which are unevenly distributed due to the constant creation at mid ocean ridges and destruction at subduction zones
- Distributed accross globe as continental and oceanic crusts
- Water stored in fault zones, soil and rocks mainly as groundwater OR in permafrost
Explain the global distribution and size of the hydrosphere
- Includes all the water on Earth in solid, liquid or gas form as saline or fresh water
- Ocean’s contain largest amount
Explain the global distribution and size of the cryosphere
- All parts of Earth’s system where it’s cold enough for water to freeze
- Largest amount in ice caps which are vast layers of ice covering land masses
- Glaciers (large masses of ice that form on mountains which are smaller than ice sheets) are distributed worldwide but concentrated in high altitude mountain ranges and are retreating due to climate change
- Permafrost is soil or sediment which remains frozen for 2+ years. Distributed in polar regions and holds large amount of carbon instead of water.
- Sea ice floats on ocean surface in polar regions and is only a short temporal store but is useful in albedo effect and doesn’t contribute to rising sea levels
Explain the global distribution and size of the atmosphere
- Layer of gas between the Earth’s atmosphere and space which is held in place by gravity
- Composed mainly of Nitrogen 78%, Oxygen and Argon.
- Lower atmosphere contains water vapour
- Densest nearest Earth’s surface
Explain the features of Earth as a system
- Closed system
- Broken down into subsystems
- Matter and energy can move between subsystems and cycled between them
- Cascading system
Explain the process of evaporation
Occurs when liquid water changes state into a gas, becoming water vapour and gaining energy from solar radiation
Explain the process of condensation
- Occurs when water vapour changes state to become a liquid by losing energy to its surroundings. Vapour cools to its dew point.
Give a long term change to evaporation rates
- During last glacial period, temperatures were low so evaporation was low (long term change)
Give % of fresh water frozen in cryosphere
69
Give % of freshwater stored in lithosphere as groundwater
30
Give % of freshwater stored as water vapour in atmosphere
0.04
What % of Earth’s fresh water is contained within the Antarctic ice cap ?
90
What % of water is stored as liquid fresh water on Earth’s surface in hydrosphere ?
0.3
What % of water on Earth is freshwater ?
3
Where in the world has there been a steep decline in groundwater due to salinity of aquifers and fresh water due to over abstraction of resources ? (change in lithosphere store)
California’s central valley
Give statistic for sea level rise due to increase in store of hydrospheric water ?
3.3mm sea level rise since 1993
In which region has global precipitation due to increased evaporation from climate change affected the worst ?
Carribbean
Give the statistic for the interglacial period which reduced sea levels and increased cryospheric store of water
During last ice age 20,000 years ago, 30% of Earth’s land surface was covered by glaciers and ice sheets
How long does water stay in soil for ?
1-2 months
How long does water stay in rivers for ?
2-6 months
How long does water stay in deep groundwater stores for ?
10000 years
How long does water stay in glacier stores for ?
20-100 years
What are the 2 largest ice sheets where water is locked up in the cryosphere ?
Antarctica and Greenland
What happens when rising sea levels destabilise ice shelves ?
Triggers calving and further melting
