1. Structure and processes within hydrosphere
WATER….
Structure and processes within hydrosphere

2. Water Earth is ¾ water Water breakdown Oceans -97.3% Frozen - 2.1%
Underground (aquifers) – 0.6%
Lakes and rivers – 0.01%
Atmosphere – 0.001%

3. Distribution of Water on Earth

4. Properties of Water Cohesive – sticks to itself
Adhesive – sticks to other materials
High specific heat – takes lots of energy to increase/decrease temperature

5. Properties of Water Water is polar Polar likes polar
Oil is not polar – oil does not mix

6. Properties of Water Density = 1 g/mL
Mass/volume (room temp)
Density is effected by temperature and salinity
Most dense at 4⁰C
Least dense - solid
Only substance to EXPAND when solid
Why is this a good thing?

7. Properties of Water Density influences ocean currents
Warm water flows from equator to poles
Cold water flows from poles to equator

9. Water Cycle Movement of water in, on, and above earth’s surface
Constantly changing forms; ice, water, vapor

10. Water Cycle
Flows over the land
Runs off
Infiltrates
Evaporates

12. Water Cycle Evaporates –moisture in atmosphere; forms clouds
Rain to Run off – streams, rivers, lakes, oceans, etc
Rain to infiltration – absorbed by vegetation, fills gaps in earth, becomes ground water

13. Water cycle Which would allow water to flow through more easily?
Notice the gaps!!!!
Easiest
Most Difficult
2nd Easiest

14. Water Cycle Create mural of water cycle Include the following:
Run off, precipitation, evaporation, infiltration, condensation, and transpiration
Define each term on the back of your mural
Can be found on page in blue Earth Science Book

15. River Basins
An entire geographical area drained by a river and its tributaries
Characterized by all runoff being taken to same outlet

16. Watersheds
Smaller area of land that drains to a smaller stream, lake or wetland
Many smaller watersheds within a river basin.

17. Ground Water
Ground Water: the water that lies beneath the ground surface
filling cracks and pores in all types of rock
Source
rain and snow that falls to the ground, some percolates down into the ground

18. Porosity and Permeability
Porous: a rock that holds much water
Permeable: a rock that allows water to flow easily through it
Impermeable: a rock that does not allow water to flow through it easily

19. The Water Table
water table: the upper surface of the zone of saturation

20. Aquifers
Aquifer: a body of saturated rock or sediment through which water can move easily
sandstone, conglomerate, limestone,
bodies of sand and gravel

21. Movement of Groundwater
Percolates into ground (downward)
May travel down slope
Moves easily through porous rock and not through compacted rock or rocks w/o pores

22. Ground Water and Flooding
Ground becomes too saturated – leads to flooding
saturated zone: the subsurface zone in which all rock openings are filled with water

23. Ground Water and Flooding

24. http://video. nationalgeographic

25. Human Use of Water

26. Wells
Well: cylindrical hole dug to penetrate aquifer within saturated zone
Recharge: addition of new water to aquifer

27. Balancing Withdrawal and Recharge
Not balancing can result in:
a regional water table dropping
the ground surface settling because the water no longer supports the rock and sediment
Subsidence of the land surface caused by the extraction of ground
water, near Mendota, San Joaquin Valley, CA. Signs on the
pole indicate the positions of the land surface in 1925, 1955, and
1977. The land sank 30 feet in 52 years.

29. Balancing Withdrawal and Recharge
Towns may use artificial recharge to increase recharge
Water is stored in infiltration ponds = increase the rate of water percolation into the ground

30. Groundwater Pollution
chemicals used for agriculture can find their way into groundwater
rain can also leach pollutants from city dumps into ground-water supplies

31. Groundwater Pollution
May affect water years from now
May take a long time to reach water

32. Groundwater Pollution
Saltwater Intrusion
Movement of saline water into freshwater aquifers
Contamination of drinking water
Salt water is denser, as freshwater is leached, salt water can take its place

33. Surface water Pollution
Non-point pollution – pollution from many sources
Sedimentation, stormwater runoff, etc
Not easily traced
Point-pollution – pollution from one source
Easily traced and easily taken care of

34. Water Treatment
Most water that goes down drains in urbanized areas are treated
Removal of sludge from water
Very toxic waste that we must dispose of

35. Water Treatment Drinking water from salt water
Desalination – removal of salt from saltwater
Takes lots of energy

36. Conservation Measures
1972 – Clean Water Act “restore and maintain the chemical, physical, and biological integrity of the nation’s waters.”
1972 – Marine Protection, Research, and Sanctuaries Act
1975 – Safe Drinking Water Act (groundwater and surface water)
1987 – Water Quality Act

37. Conservation Measures
Need to protect water sources for our future
Increase population = increase need for water
Increase population = increase pollution
Must take care of our water for our survival!

38. Hydroelectric Dams Build barrier in valley to retain freshwater
Water rises to the same level as top of barrier
Uses water flow to also generate clean electricity.

40. Hydroelectric Dams Positive effects
Long term large body of freshwater resource
Prevents water from reaching ocean quickly
Provides large areas with freshwater
Clean electricity
Recreation
Control water flow – less chance of flooding

41. Hydroelectric Dams Negative effects (down stream) Reduces water flow
Less water for down stream individuals
Less water for wild life
Less nutrients carried
Migrating/reproducing organisms cannot pass dam
Dam break = massive flooding

42. Hydroelectric Dams Negative effects (upstream)
Displaces wildlife/destroys lower level environments
Floods towns/homes below level of dam
Stagnant water = decrease in water quality

43. Hydroelectric Dams Much debate over building new power dams
Several dams being destroyed to allow natural flow
Energy/water crisis
Are dams our answer??