Monday, September 30, 2013

The scarcity of water

Image above: Amazing representational visualisation from the United States Geological Survey showing the distribution of water on Earth - not a lot of fresh water really!!!

The image shows that in comparison to the volume of the globe the amount of water on the planet is very small - and the oceans are only a "thin film" of water on the surface. The blue spheres represent all of Earth's water, Earth's liquid fresh water, and water in lakes and rivers

The largest sphere represents all of Earth's water, and its diameter is about 860 miles (the distance from Salt Lake City, Utah, to Topeka, Kansas). It would have a volume of about 332,500,000 cubic miles (mi3) (1,386,000,000 cubic kilometers (km3)). The sphere includes all the water in the oceans, ice caps, lakes, and rivers, as well as groundwater, atmospheric water, and even the water in you, your dog, and your tomato plant.

Water scarcity on Earth

"Our unique island home still claims the title of being the driest inhabited continent on earth, and with droughts projected to increase, it’s getting drier. Australia has the least amount of water in our rivers, the lowest run off and the smallest area of permanent wetlands than any other continent?. One third of the continent produces almost no run off at all; and our rainfall and stream flows are the most variable in the world. Three quarters of our land is arid or semi-arid and a massive 44 per cent is desert."

 Water has a place in the Australian Curriculum: Geography, appearing as a distinct topic in Year 7 (Water in the world) and as an important component of Year 4 in relation to the content description: "natural resources provided by the environment, and different views on how they can be used sustainably." Water has a further focus in the curriculum in the Year 10 'Environmental change and management' topic, where students can choose to study 'inland water' as an option to explore sustainability issues.

The image above showed us the relative amount  fresh water on the Earth, but where is the water on Earth?

Despite the amount of water that makes up our ‘Blue Planet’, water scarcity is one of the biggest problems facing our Earth. Water is an essential resource for life and good health. A lack of water to meet daily needs is a reality today for one in three people around the world. Globally, the problem is getting worse as cities and populations grow, and the needs for water increase in agriculture, industry and households. The health consequences of water scarcity, its impact on daily life and how it could impede international development is a critical issue for the geography classroom. It certainly has a place in the Australian Curriculum: Geography at Years 7 and 10.
The 10 facts about water scarcity on the United Nations World Health Organisation website (look at the related links on the page) provides some great information on water scarcity. 

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