The Hydrosphere

A) Earth’s outer layer of water

( solid , liquid , gas )

B) Inland waters

1) Freshwater (lakes, rivers, etc)

2) Watershed

a) all inland waters drain into same body of water

b) depends on topography , geology, climate , vegetation , development of land

C) The Oceans

1) water temperature

a) depends on depth

i) light energy limited … water temp cools drastically ~200m (thermocline)

b) depends on season

i) winter vs summer

c) depends on latitude

i) equator vs temperate zones

2) salinity

a) ~ 3%

b) from rocks eroding/movement over rocks

c) glaciers, rivers dilute salinity

3) ocean circulation

a) surface currents (ex. Gulf Stream)

i) mostly due to wind (0-400m)

b) subsurface current (~ 800m)

i) due to density variations between water layers

- affected by salinity and temp.

c) thermohaline circulation

i) waters moving throughout the globe on a ‘conveyor belt’

ii) important in regulating Earth’s climate

D) The Cryosphere

1) frozen water on Earth

2) pack ice

a) floats on oceans, North & South poles

i) aka: ice floes (smaller pieces)

b) area reduced due to global warming

3) glaciers

a) 79% of Earth’s fresh water

b) mass of ice on land

i) ex. Greenland, Antarctica

c) ice breaks off into oceans (icebergs)

i) causes water levels to rise

ii) decreases salinity of water

- does not sink as fast = may change ocean circulation?

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E) Energy Resources

1) hydraulic energy

a) water falls and rivers

i) hydroelectric dams

b) waves and ocean currents

i) turbines to be developed

F) Pollution and Degradation

1) chemical pollution

a)domestic, industrial, agricultural,

and navigational sources

2) thermal pollution

a) from factories

b) decreases concentration of oxygen

3) Eutrophication

a) decrease in oxygen levels due to the accumulation of organic matter and nutrients (ex. phosphorus, nitrogen)

4) Threats at sea (don’t forget rivers & lakes & …)

a) London Convention 1972

b) pollution still exists

i) oil spills (hydrocarbons)

ii) the Great Pacific Garbage Patch