Second Class Session 29 September 2010

World Water Supplies: The Coming Crisis

Mendoza, Argentina ©eop

Session II: The Physical Geography of Water Supplies: Some Illustrative Materials

Thanks to a computer glitch, three videos I had wanted to use with the session were unavailable.  Below are those videos and a couple of notices. I shall post the outline of the session in a day or two.

I. World rainfall by Month, 1998-2009

Source: NASA Earth Observatory

II. World Snow Cover

Source: NASA Earth Observatory

3. Great Artesian Basin of Australia

Source: Government of Australia

The following information is thanks to one of our class members:
"Liquid Assets - The Big Business of Water   'The host explores the coing water crisis as fresh water becomes harder to find"  CNBC Thursday 30 October 9-10 pm
According to other class embers CNBC is available at Channel 68 on Cox cable and 102 on Verizon. The CNBC website does not give much additional information, but it sounds as if the broadcast will be worth watching.

Once again, by next session 6 October, please work out your water footprint. Go to the website at http://www.waterfootprint.org/?page=cal/WaterFootprintCalculator

Artesian Water

 1914 Label for Olympia Beer 

The beer was brewed until the 1980s in Tumwater, Washington (adjacent to Olympia) using artesian water, or so the brewery claimed. Today that beer brand is brewed in Southern California.

From the time I was a small child I remember people talking about artesian water, and until I was almost an adult I believed that it was somehow different from standard surface water or the water coming out of the tap. Advertising, including that for a popular brand of beer in the Puget Sound region, suggested that somehow artesian water tasted better or was more healthful. Based on marketing for Fiji water, a widely distributed brand of bottled water, that misconception persists.  In fact artesian is a description of the source and not of the water itself. Artesian water can be almost pure or nearly saturated with chemicals. Its primary trait is that it came from an underground aquifer where water is under pressure. When the aquifer comes to the surface a flowing or artesian well occurs. Many springs are of this sort.

A diagram of an artesian system where ground water is under pressure and rises to the surface when there is an opening. Source: http://www.littledippers.com/geocaching/ArtesianWell.jpg

Artesian wells are often a selling point for a property, especially a large property to be used for grazing where permanent surface water is distant or rare. In arid areas artesian seeps and wells are often the only source of water for many kilometers and thus are especially prized. In a later posting I plan to write a little about Australia's Great Artesian basin. The intense aridity of the outback would preclude almost all human use in many areas were it not for the water the artesian flow provides.

Artesian wells are but one aspect of ground water, a topic about which I shall have a great deal to say.