Earth’s Water Resources

1. Earth’s Water Resources By: Alessia, Luki, Jasmine and Amanda

2. Fresh Water • It has been estimated that the amount of fresh water on Earth could support 20 billion people, more than three times the current population of the world. Reality is much different considered these three factors: • Most fresh water exists in forms that are not directly accessible, for example, in polar glaciers and permafrost, and as water vapour in the atmosphere. • Large functional freshwater reserves are often not located where the demand for water is greatest. Example, in Canada 60 percent of rivers drain north, away from where 90 percent of Canadians live. • In wealthy Old Core nations, water pollution can be a significant conflict. Water pollution is a problem almost everywhere. The devastating reality is that hundreds of millions of people are forced to rely on unsafe water sources. As a result, millions die of water-borne disease each year.

3. Pollution of Surface Waters Human activity is the main source of pollution of fresh water. Urbanization, industry, mining, forestry, agriculture and shipping are associated with the activities that affect water quality.

4. Sewage Waste • Human and animal wastes contain bacteria that spread disease. When these wastes enter the water supply, people may contract serious illnesses such as cholera, diarrhea, intestinal parasites and many more. • About 1.5 billion people worldwide do not have access to safe drinking water, and about another three billion do not have adequate sanitation , that is, the ability to dispose of their sewage safely. • 80 percent of the infectious diseases in Far Periphery, Near Core, and New Core countries result from impure water. • Many communities in Old Core nations and most in the rest of the world do not have adequate sewage treatment.

5. Chemical Waste • The chemical by-products of manufacturing often reach our water bodies and, as a result, pose a threat to our health • Some industrial pollutants are biodegradable which is they break down as a result of natural processes in the environment • Care needs to be taken when flushed down so that it does not upset the natural environment • Lead, copper and arsenic are very dangerous even in small quantities because they will never be biodegradable and break down • Large amounts of phosphates from laundry detergents, and nitrogen from industry and agriculture enter Lake Erie and fertilized the growth of aquatic plants. Americans depend on Lake Erie for their drinking water

6. ..Cont’d • In 1972, Canada and the U.S signed the first Great Lakes Water Quality Agreement, and steps were taken to reduce phosphate discharge into the great lakes. • In 1995, the International Joint Commission (IJC), was put into position to solve the chemical-waste problems in the Great Lakes logically but very expensive. • A study by the World Bank in 2003 found that Old Core countries made some improvement in the water quality of their rivers. River-water quality in many New Core countries generally showed little change, while river-water quality in other New Core countries and in the Periphery continued to deteriorate. • Generally approaches to remediation can be considered in four ways: • Source Control: The first step is to stop the addition of more contaminates. • Natural Recovery: The best approach is to give nature a chance to solve the problem. The two major important ways that this happens occurs when natural sedimentation covers dangerous materials on lake and river bottoms and when biological processes break down dangerous compounds. • Environmental dredging: When natural recovery is not enough, large dredging machines can remove dangerous materials. Materials that are removed are placed in specially designed landfills. • Thick-layer capping: The contaminated materials are sealed off from the water by placing 20 to 100 cm of clean materials such as clay, or sand on top of them.

7. Agriculture Wastes Irrigation washes away soil sediments that then clog waterways, destroy fish habitats and fill in wetlands Excessive use of pesticides that frequently end up in lakes, ponds, and rivers, has been linked to high rates of cancer and birth defects.

8. Groundwater Open aquifer – water percolates into the aquifer from above, through permeable (having small spaces through which water can move) soil, rock and sediments. Closed aquifer – water cannot percolate into the aquifer from directly above because the aquifer is surrounded, on top and bottom, my impermeable rock or sediments, such as shale or clay. Instead, water enters the aquifer from a source at a higher elevation and often a considerable distance away. Much of the water in a closed aquifer may be fossil water – from rain that fell thousands or even million years ago. The Ogallala Aquifer- is an important source of water in the US. This largely closed aquifer underlies a major agricultural area that is part of eight states, stretching almost 1300 kilometers from north to south and 650 kilometers from east to west.

9. Fossil Water Use in Saudi Arabia Saudi Arabia relies heavily on fossil water. Saudi Arabia’s water comes from a combination of renewable water from aquifers, desalinated water and reused water. The remaining two thirds comes from fossil water in underground aquifers. Desalinated water – seawater from which salt has been removed.

10. Wetlands - can be found in every major climatic zone on earth -known as different names: swamps, marshes, bogs, fens, tidal marshes, mangrove swamps. - have been filled in or drained for residential, industrial and especially agricultural purposes. - many factors have led to the protection of wetlands in Old Core countries especially. -24% of wetlands are found in Canada. *-temporary water storage sites that can recharge aquifers moderate stream flow and lessen floods *- vegetation holds soil in place and anchors shore lines. *- provide habitats and breeding grounds for fish, birds and mammals, invertebrates *- natural recycling of chemicals circulates nutrients to plants and animals, used to treat sewages. *-provide people with food and fuel. see figure 17-11

11. Managed Water Large scale dam projects present a variety of issues related to preserving the earths freshwater supply. -see figure 17-12 -Benefits of large dam projects/ negative (in text book, figure 17-13)

12. Irrigation Schemes -large scale schemes are associated with large dams. - 40% of the world supply is produced in this land, this is good but they are things to consider. - hot dry climates- water evaporates. -when water evaporates it causes a salt and the salt is poisonous to the earth. -this makes farming impossible.

13. Sustainability It costs about as much to tear down a dam as it does to build one

14. Alternatives to Large Dams -building small dams that manage water on a local rather than regional scale -planting trees to hold a rainwater back until it has a chance to sink into the ground where it can be accessed with wells. -choosing to grow crops require less water -using drip irrigation (see figure 17-16) -reducing waste since only 40% of water diverted for agriculture actually contributes to food production.

15. Water transfer • In many parts of the world, fresh water is in short supply; in other parts, it is abundant. One method of dealing with the inequity is to transfer water from one place to another. Consider the two sides: • In favour of transfer- supporters of transfers (often from parts of the US that are short of water), argue that Canada has an enormous amount of surplus fresh water- an amount far beyond what the country needs or is likely to need in the future.Canada is happy to export non-renewable sources like oil, gas, so why not export renewable water? A properly managed water-export industry would provide jobs and money that could benefit Canada, and help parts of the US that are dry now and likely to be drier still as a result of global warming.

16. Cont’d • In opposition to transfer- those who oppose transfer (including environmentalists and Canadian nationalists). Although fresh water is plentiful in Canada, it is located in the North, far away from where it is needed for human activities. From this, it is made that there is much less water available for transfer than to the US that would first appear.They also say that that higher global temperatures will increase evaporation and change precipitation patterns, we may need all the water we have.

17. Preserving Our waters In 1977, after years of enduring the indiscriminate fishing practices of other nations, Canada declared a 370 kilometre exclusive fisheries zone extending from its coastlines. In doing so, Canada took upon itself the protection of its coastal waters. In 2007, (Nations with jurisdiction in the Artic Ocean basin are Canada, Russia, the US, Norway and Denmark). Russia declared that its jurisdiction extended from its coastline to the North Pole, which was thought to contain rich reserves of oil, and natural gas, gold, diamonds, and other minerals. In 1994, the United Nations convention on the Law of the Sea, (UNCLOS) put into force a legal agreement for promoting peaceful uses of the worlds oceans, the equitable use of ocean resources and the protection of marine environments.

18. Question time! Saudi Arabia does not rely on fossil water heavily. True or False?

19. FALSE They rely heavily on fossil water.

20. The countries involved with the Artic ocean basin include: a) Canada, us, china, Australia & Denmarkb) Russia, Australia, US, Canada & JapanC) us, Canada, Russia, Norway & Denmarkd) Norway, Denmark, Us, Japan & Australia

21. C) US, Canada, Russia, Norway & Denmark

22. It costs It costs about as much to tear down a dam as it does to build one. True or False?

23. TRUE

24. The main source of water pollution is: A) MiningB) ForestryC) AgricultureD) All of the above

25. D) All of the aboveHuman activity is the main source of water pollution which includes things such as mining, forestry and agriculture.

26. In favor of transfer is supporters of transfers (often from parts of the US that are short of water)True or False?

27. TRUE

28. _________ leads to high rates of cancers and birth defects. A) Not exercising B) Excessive use of pesticidesC) Bad cleaning habitsD) A & B

29. B) Excessive use of pesticides

30. Most fresh water exists in forms that are directly accessible. True or False?

31. FALSEMost fresh water exists in forms that are not directly accessible, for example, in polar glaciers and permafrost, and as water vapour in the atmosphere.

32. VIDEO http://www.youtube.com/watch?v=QqNUTlY5foQ