2. WATER - The Hydrosphere
Objectives:
Define “hydrosphere”
Identify & describe the processes involved in the water cycle
Explain how the ocean regulates Earth’s temperature

3. The Hydrosphere All the water on or near Earth’s surface Oceans Lakes
Rivers
Wetlands
Icecaps and icesheets
Soil
Subsurface groundwater
Clouds and atmosphere

4. Water Cycle Review
What are the main processes involved in the water cycle?

5. What powers the Water Cycle?

6. Water Cycle Involves Transfer of Energy
Water absorbs heat energy
When enough energy is absorbed, water changes from liquid to gas (evaporation)
Energy is transferred from Earth’s surface to atmosphere
80% of water entering atmosphere originates from oceans between 60oN and 60oS latitude
Water moves to a cooler area and condenses
During condensation, water releases heat
Warms surrounding atmosphere

7. The World Ocean 71% of Earth’s surface Key functions:
1. Absorb/store energy from sun
2. Regulate temperatures in atmosphere

9. Oceans Regulate Global Temperatures
Water absorbs/releases heat more slowly than land
Temperature of atmosphere changes more slowly
Currents that circulate warm water (ex. Gulf Stream) cause land areas they flow past to have more moderate climate
2008 Worldwide Sea Surface Temperatures

11. WATER RESOURCES OBJECTIVES – Identify where Earth’s water is stored
Explain why water is considered a limited resource
Compare surface water resources and groundwater

13. TWO TYPES OF WATER SURFACE WATER – freshwater on Earth’s land surface
Lakes, river, streams, wetlands
GROUNDWATER – freshwater beneath Earth’s surface
In sediments and rock formations

14. SURFACE WATER – IT STARTS WITH A DROP
Buba River, Guinea-Bissau
SURFACE WATER – IT STARTS WITH A DROP
Precipitation falls to the ground, then flows into streams, streams flow into rivers, rivers flow into larger rivers
RIVER SYSTEM – flowing network of rivers moving across land

16. WATERSHEDS OF THE WORLD
WATERSHED – the area of land drained by a river
affected by – melting snow & rain, use, lack of rain and POLLUTION ANYWHERE IN THE WATERSHED
Weekly Average Flow of World Watersheds

18. GROUNDWATER
Forms when surface water percolates / infiltrates through soil into the rocks below
Essential for human survival – most freshwater is underground

19. Aquifers

20. Recharge Zone
Area of Earth’s surface through which water percolates down into aquifer Environmentally sensitive – any pollution in recharge zone can enter the aquifer

21. Aquifers can take tens of thousands of years to recharge/refill
What could interfere with recharge?

22. Well – a hole dug or drilled to reach water
More reliable as a source of water than surface water and cleaner. WHY???
Drilled to reach below water table…WHY?
What happens if water is removed faster than it can be recharged?

23. Water Use & Management
We all live downstream.

24. Section 2 : Water Use and Management
GOALS:
Identify how water is used in home, industry and agriculture.
Explain how and why water is treated before coming to your home.
Describe ways to increase water supplies
Identify ways to conserve water
TERMS:
potable, pathogen, dam, reservoir, desalinization

25. 783 million people do not have access to clean water
almost 2.5 billion do not have access to adequate sanitation
6 to 8 million people die annually from the consequences of disasters and water-related diseases

26. How Much Water Do You Use
Average person in US uses ~100 gpd
Average person in India~ 40 gpd

27. Making Water Safe Potable: safe to drink
Most water needs to be treated
Pathogens: organisms that cause diseases
Bacteria, viruses, worms

28. Uses of Water Industrial Water Use: 19% of worldwide water use
To make “stuff”
Dispose of waste
Cooling power plants (most)

29. Uses of Water Agriculture: 67% of worldwide water use
Irrigation: providing water to plants )other than by precipitation)
80 gallons to produce 1 ear of corn
1 lb. beef = 1,000 gal.
LOTS OF WATER

30. Irrigation
Where does all this water come from?

31. From the ground –
The figure shows ground subsidence (sinking) due to removal of groundwater
- 9 meters or 29 feet
or 7 inches per year!
WHY? To grow our food

33. What can you learn from this chart?

34. Water Management Humans have altered water flow for thousands of years
Engineering
Dams, canals, pipes, towers bring water to where it is needed

37. California aqueduct brings water hundreds of miles, across deserts, mountains

38. Dams and Reservoirs Reservoir: an artificial lake often behind a dam
Flood control
Recreation
Water supply
Drinking
irrigation
Generate electricity
20% worldwide

39. Pros and Cons of Dams Downstream cropland and
Large losses
of water through
evaporation
Flooded land destroys forests or cropland and
displaces people
Downstream flooding is reduced
Downstream cropland and
estuaries are deprived of
nutrient-rich silt
Reservoir is useful for recreation and fishing
Can produce cheap electricity (hydropower)
Migration and spawning of some fish are disrupted
Provides water
for year-round
irrigation of
cropland

41. Water Conservation
Fastest, easiest way to increase water supplies is to use less water
Agriculture
Industry
At home
What are some ways you can conserve water?

42. Irrigation As much as 80% normally evaporates
Drip Irrigation, reduces that number greatly

43. Desalinization Removing salt from salt water Has a lot of promise
Very energy intensive
Very expensive
What to do with waste?
Future?

44. Transporting Water
The Nordic Water Supply Company in Oslo, Norway, has signed a contract to deliver 7 million cubic meters of water per year in bags to northern Cyprus.

45. Section 3: Water Pollution
GOALS:
Compare point-sources and non-point sources of water pollution
Describe the 5 classifications of water pollution
Explain why it is difficult to clean up groundwater
What does the Clean Water Act do?
TERMS: water pollution, point-source, non-point source, wastewater, biomagnification, eutrophication

46. Freshwater animals are vanishing faster than those on land or at sea.

47. What is Water Pollution?
Water Pollution: is the introduction of chemical, physical, or biological substances that affects organisms that depend upon it
Many types of water pollution

49. Point Source Pollution coming from one single place Leaking tanker
Pipe from a factory
Leaking underground storage tank
Can easily be identified and traced

50. Point Sources – easily identified

51. Non-Point Source
Comes from various sources that are hard to identify and may be spread over a large area
Runoff from farms
Runoff from cities
Difficult to identify
Hard to control
HUGE PROBLEM – accounts for 96% of water pollution

52. How can a farmer in Montana affect a shrimp farmer in Louisiana?
NON-Point

53. Principal Water Pollutants
Pathogens – disease causing organisms
animal wastes
Organic Matter – animal and plant remains
Organic Chemicals – pesticides, fertilizers
Inorganic Chemicals – salts
Heavy Metals – lead, mercury, arsenic
Physical Agents – thermal & suspended sediments

54. Types of Water Pollution 1) Wastewater
Water that flows down the drain
What’s in it?
Where does it go? (out-of-sight, out-of-mind)
Is it harmful?

56. 2) Eutrophication Natural process – however -
Too many nutrients (N & P) in the water causes algal blooms and decreased oxygen in water
Causes “dead zones” in water
Little or no oxygen

57. 3) Thermal Pollution Occurs when temperature of water rises rapidly
Power plants
Factories cooling equipment
Causes fish kills
Decreases oxygen in water – suffocates aquatic organisms

59. 4) Groundwater Pollution
Pollution that percolates down from land or surface water pollution
Fertilizers, pesticides, leaking underground tanks
Many leaking underground tanks

60. Groundwater Pollution
What could happen if recharge zone is polluted?
Common pollutants in recharge zone:
1. Nitrates
2. Petroleum products
3. Pesticides
4. Heavy metals
5. Industrial pollutants

61. Difficulties with cleaning groundwater pollution:
1. Recharge is very slow; 100s – 1000s years to recycle
2. Water dispersed over large areas
3. Pollutants can cling to particles that make up aquifer
Best course of action is to prevent groundwater pollution

62. 5) Ocean Pollution Pollutants directly or indirectly put into oceans
85% of ocean pollution is land based
Oil spills
Runoff
River pollution
Cruise Ships
Development along coasts
Increasingly a problem

63. 15 BIGGEST OIL SPILLS

64. Water Pollution and Ecosystems
Can cause immediate damage to an ecosystem
Effects can be far reaching
Some pollutants build up (they do not decompose quickly)
Biomagnification is the accumulation of pollutants at successive levels of the food chain.

65. Biomagnification

66. in an individual
in a food chain

67. WETLANDS – VITAL TO THE PLANET
Serve as a buffer between land & sea
Absorb pollutants
Absorb excess water
Habitat for wildlife

68. Cleaning Up Water Pollution
1969 Cuyahoga River in Cleveland caught fire
1972 Congress passes Clean Water Act
1970s Environmental Activism/Awareness

69. Cleaning Up Water Pollution
Clean Water Act of 1972 was to “restore and maintain the physical, chemical and biological integrity of the nation’s water.”
Fishable and Swimmable
Better, but… still many polluted water bodies

71. What does the future hold for water on planet Earth?
The Ocean: A Driving Force for Weather and Climate
What does the future hold for water on planet Earth?
Climate Change?
Melting Glaciers?
Human Population Rising?
Water Scarcity?