1. Water Resources 1. Hydrologic Cycle and Water Reservoirs 2. Floods and Flood Control 3. Use of Water 4. Water Composition 5. Water Problems

2. Hydrologic Cycle

4. Distribution of Water (from Resources of the Earth 1972 data) TypeLocationVolume (l)Percent SurfaceLakes1.25 x 10 17 0.009 Saline lakes/seas1.04 x 10 17 0.008 Streams1.00 x 10 15 0.0001 SubsurfaceVadose6.7 x 10 16 0.005 Groundwater (to 750 m)4.17x 10 18 0.31 Groundwater (below 750m)4.17x 10 18 0.31 Other ReservoirsIcecaps, glaciers2.9 x 10 19 2.15 Atmosphere1.3 x 10 16 0.001 Oceans1.32 x 10 21 97.2

5. Distribution of Water h ttp://ga.water.usgs.gov/edu/waterdistribution.html (1997 data) h ttp://ga.water.usgs.gov/edu/waterdistribution.html SourceVolume (km 3 )% Fresh% Total Oceans1338 x 10 6 96.5 Ice caps/glaciers24 x 10 6 68.71.74 Groundwater23.4 x 10 6 Fresh10.53 x 10 6 30.10.76 Saline12.87 x 10 6 0.94 Soil Moisture.0165 x 10 6 0.050.001 Permafrost0.3 x 10 6 0.860.022 Lakes0.1764 x 10 6 0.013 Fresh0.091 x 10 6 0.260.007 Saline0.0854 x 10 6 0.006 Atmosphere0.0129 x 10 6 0.040.001 Swamp Water0.0115 x 10 6 0.030.0008 Rivers0.00212 x 10 6 0.0060.0002 Biological Water0.00112 x 10 6 0.0030.0001

6. Bibliographical Acknowledgment referenced publication for content development Peixoto and Kettani, 1973 The Control of the Water Cycle Scientific American - Vol. 228 - pp. 46-6

7. Heat Capacity of Water This means that water has the ability to absorb and hold heat with a minimal change in temperature Why? When water evaporates it takes 540 cal/gm. This means that evaporation creates a cooling effect. Ice going to water releases 80 cal/gm, thus releasing heat

10. World water resources http://www.worldmapper.org/

11. Evaporation (mean annual U.S.) http://geochange.er.usgs.gov/sw/changes/natural/et/

12. http://ga.water.usgs.gov/edu/watercycleevapotranspiration.html Evapotranspiration

13. Mean Annual Evapotranspiration

14. When ppt >>> e/t Then we get rivers and streams Eastern NAwater surplus Western USwater deficiency Plays a role in population density in U.S. and Canada

15. Freshwater Reservoirs Rivers and Streams Lakes Icecaps Groundwater

16. Much greater in volume than either lakes or streams Non-renewable in our lifetime

17. Water Table Surface below which pores and fractures of rocks and overburden are water filled

18. What is an aquifer? Geologic formation that possesses porosity and permeability

19. Water Resources 1. Hydrologic Cycle and Water Reservoirs 2. Floods and Flood Control 3. Use of Water 4. Water Composition 5. Water Problems

20. Surface Water/Floods/Flood Control Surface water is water that flows off the land in streams and rivers What is it dependent upon??

21. Amount of precipitation Slope and Length of drainage basin Rock and soil type of drainage basin Vegetation Extent of impermeable areas

22. Red River Discharge Hydrograph

23. When does flooding occur? When surface run-of exceeds a normal stream channels capacity and water spreads out onto the flood plain Is this a problem?

24. What do we do to minimize flooding? 1. build dams 2. build levees 3. create channels (channelization) 4. Moveable damsThames

25. Dams: pro 1. Do help with flood control 2. Supply electricity 3. Provide recreation 4. Sources of water for irrigation 5. Increases groundwater Does anyone see some inconsistency here?

26. Dams: con 1. Sediment catchment 2. Increased evaporation 3. Loss of land 4. Interruption of river transport and fish migration 5. Environmental alteration

27. Some Dams Aswan High Dam

28. Glen Canyon Dam

29. Hoover Dam

30. Three Gorges Dam http://svs.gsfc.nasa.gov/vis/a000000/a003400/a003433/#topm http://svs.gsfc.nasa.gov/vis/a000000/a003400/a003433/#topm

32. Levees

33. Channelization Replacement of a meandering stream by a deeper, straighter channel

34. Drawbacks Transfer of flooding Flood plain doesnt get new sediment

35. Kissimmee river in Florida

36. Drawbacks of Channelization Increased erosion Transfer of flooding downstream Reduced natural filtering of water and drainage basin Loss of wetlands Reduction in available water for general use Less evapotranspiration Less infiltration Lower ground water levels Larger variations in flow rates Reduction in wildlife