1. Global Water Resources

2. Freshwater vs. Saltwater

3. Fresh Water, a renewable resource, is continually recycled and returned to the ecosystem through the hydrologic cycle.
As weather systems move through they deposit moisture in the form of rain, snow, hail or sleet.

4. Watershed: an area of land that captures rainfall and other precipitation and funnels it to a lake or stream or wetland

5. Water enters a watershed as either
precipitation directly into surface water
runoff from the surrounding land
Groundwater
inflow from upstream lakes.

6. Precipitation falling on the land infiltrates into the ground through percolation to replenish the groundwater.
When water accumulates below ground in the spaces between soil and rock, it is called groundwater.
Groundwater is contained in aquifers- porous, sponge like formations of rock, sand, or gravel that hold water

8. The water table is the boundary between the upper layer, or zone of aeration, and the lower layer, or zone of saturation, which is completely filled with water.

9. Water leaves the system through evaporation from the land and water surface or through transpiration, a process where moisture is released from plants into the atmosphere.

10. Water also leaves the system through
groundwater outflow
consumptive uses
drinking water, industrial/agricultural systems, etc.
Diversions
outflows to downstream lakes or rivers.

13. Salt water is more dense than freshwater
Salt makes water heavier
Heat makes water less dense

14. Ocean Circulation

15. Surface Current: an ocean current that generally flows in the upper 1000m of the ocean. Caused by:
Wind
Earth’s Rotation
Presence of Continents

16. Ocean Current: any continuous flow of water along a broad path in the ocean
Density Current: current in the deep ocean, driven by gravity and differences in density (NOT wind!)
Move slowly compared to surface currents

17. Warm Currents: flow away from the equator on the western side of ocean basins
Cold Currents: flow toward the equator on the eastern side of ocean basins
The temperature from these ocean currents is transferred to the atmosphere, thus affecting the climate of the areas around them!

19. Upwelling: when cold, deep water comes to the surface to replace the surface water that is pushed away by the winds
Contains large amounts of nutrients that phytoplankton need to grow
Very important to life in the ocean!

20. Downwelling: transports warm water downward, providing oxygen for deep-water life

21. Water as a resource

22. How we use water
Most uses of water are consumptive use, in which water is removed from a particular body of water and is not returned to it
Non-consumptive use of water does not remove, or only temporarily removes, water from an aquifer or surface water body

23. Agriculture
Most of this water is lost because of poor irrigation techniques

24. Industry
Water.usgs.gov

25. Industries that use the most water: Cement, Textiles, Paper
All forms of industry use water in the formation of their products or to clean, cool, or heat the machinery.

26. 95% of water use is hidden in the products you buy, the food you eat and the energy you use
wwf.org

28. Residential Use
Savingwater.org

29. How can we save water? At Home: Low-flow faucets, showerheads
Energy and water efficient washing machines and toilets

30. Xeriscaping: landscaping with less water use…less water loss
Before
After

31. Agriculture:
Drip system- 95% efficiency
Industry:
Require industries to reclaim and recycle their water

32. Surface and Groundwater issues

33. Consequences of depleting ground water: Drought
Instability, leading to sinkholes
Low water table
Diminished surface water
swfwmd.state.fl.us

34. Water conflicts in the United States
10% of U.S. watersheds are stressed to the point that the demand for water exceeds the supply
Major water sources in the United States:

35. Left Hand Side Water Source Affected States Ogallala Aquifer
TX, NM, OK, CO, KS, NE, WY, SD
Lake Mead
NV, AZ
Colorado River
CO, UT, AZ, NV, CA, NM, WY
Klamath River
OR, Klamath tribal nation
Chattahoochee River
GA, AL, FL

36. Ogallala Aquifer Lake Mead & Colorado River

37. Chattahoochee River
Klamath River

38. Global Water Conflicts
Demand for water is increasing due to…
population growth
Increasing agricultural and industrial use
less predictable rainfall due to climate change

39. The Solution…
Future water supplies may be increased by desalinization: removal of salt from salt water
Not economically feasible!
Conservation of water is Critical

40. International Water Conflicts
Nile River
Egypt and Ethiopia
Indus River
India and Pakistan
Tigris and Euphrates Rivers
Turkey and Syria
Jordan River
Israel and Palestine
Colorado River
United states and Mexico
Al-Disi aquifer
Saudi Arabia and Jordan