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POLLUTANT MOVEMENT THROUGH AIR, LAND, AND WATER
Introduction to WaterLecture 1
Consider
What is a model?
How is an equation like a model?
What did Dora Maar look like?
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Seated Portrait Of Dora Maar, 1939by Pablo Picasso
Portrait of Dora Maar, c.1937by Pablo Picasso
http://www.theage.com.au
Maps as Models
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Vermont, from actual survey [1795]Delineated & Engraved by Amos Doolittle N.H.
Published in Carey's American Atlas, 1795.
Google Earth
N44° 28’ 36.27’’ W73° 11’ 41.20’’
What is a model?
• A tool that describes something that cannot be observed directly (such as an atom) or something that is too complex to comprehend directly (like an ecosystem).
• A simplification of reality.
Types of models• Portrayals of Emotions, Events, Persons, Things
– poems, songs, paintings, dolls, etc
• Portrayal and Analysis of Spatial Patterns– maps, remotely sensed images, etc.
• Analysis of Spatial & Temporal Patterns– Provide insight, predictions, forecasts of future
conditions – enhance understandings of processes that control
dynamic behavior of eco-systems– allow comparison among alternative scenarios
How well do we understand the world from these “models”?
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Area = Length x Width
q = K * dh/dx(Darcy’s Law)
Points• Equations are models and as such are
approximations of “reality”
• The result from an equation is only as good as the error associated with the variables.
• The accuracy of the predication from an equation is dependent on the user’s understanding of the equation.
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How much water is there on earth?
• 326,000,000,000,000,000,000 gallons• 326 million trillion gallons• 1,260,000,000,000,000,000,000 liters• Global population (3 Nov 2010): 6,879,116,087 • Liters/person: 183,163,066,891 per person
http://science.howstuffworks.com/question157.htm
http://www.census.gov/ipc/www/popclockworld.html
Earth’sWater
Saline(oceans)
97%
Fresh Water (3%) Other (0.9%)
Lakes(87%)
Surface Water (0.3%)Ground
Water(30.1%)
Ice Capsand
Glaciers(68.1%)
Swamps (11%)
Rivers (2%)
Fresh Water (All)
Fresh Water (Available)
Distribution of the Earth’s Water
If ~half of Ground Water is available, then maybe ~0.75% of Earth’s Water is “available”.
http://ga.water.usgs.gov/edu/waterdistribution.html
World Water Balance (inches per year)
What is an inch of runoff?
Even at this gross level of aggregation, potential water resource problems are evident.
P = RO + Ev RO = ROGW + ROSW
Water Use in the US
(2000)
Is it “small” or “large”?
What is “consumptive
use”?
Fig 1.8 in Ward and Trimble
Water Use Trends by Source
http://pubs.usgs.gov/circ/2004/circ1268/
Water Use Trends by Sector
http://pubs.usgs.gov/circ/2004/circ1268/
How much water in 12 oz can of soda?
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How much water in 12 oz can of soda?
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Source L/can
Contents of the can 0.355
Direct withdrawlsFabrication 0.2Iron and steel 19.08Thermoelectric 3.42Other 0.45
Indirect withdrawlsIron and steel 6.13Thermoelectic 14.75Agriculture 13.27Mining 2.18Chemicals 1.44Paper 1.32Other 0.9
Sum 63.5Liters16.8gals
USGS (1976)
We often ‘use’ water without realizing it
Miller (2004)Fig. 13.6, p. 298
1 automobile
1 kilogramcotton
1 kilogramaluminum
1 kilogramgrain-fed beef
1 kilogramrice
1 kilogramcorn
1 kilogrampaper
1 kilogramsteel
400,000 liters(106,000 gallons)
10,500 liters(2,400 gallons)
9,000 liters(2,800 gallons)
7,000 liters(1,900 gallons)
5,000 liters(1,300 gallons)
1,500 liters(400 gallons)
880 liters(230 gallons)
220 liters(60 gallons)
What happens to the water we return?
Ward and Trimble Table 1.7
We use more water than most
Environment Canada (http://www.ec.gc.ca/water/e_main.html)
We pay lessfor water than
almost anyone else
Environment Canada(http://www.ec.gc.ca/water/e_main.html)
The basic structure of waterThe water molecule is a “dipole”
Water as a Solvent
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S. Berg, Winona College
Where does all the water go?
Miller (2004)Fig. 19.5, p. 482
Discharge of untreatedmunicipal sewage
(nitrates and phosphates)Nitrogen compounds
produced by carsand factories
Discharge of treatedmunicipal sewage
(primary and secondarytreatment:
nitrates and phosphates)
Discharge of detergents
( phosphates)
Natural runoff(nitrates andphosphates
Manure runoffFrom feedlots(nitrates andPhosphates,
ammonia)
Dissolving of nitrogen oxides
(from internal combustionengines and furnaces)
Runoff and erosion(from from cultivation,mining, construction,
and poor land use)
Runoff from streets,lawns, and construction
lots (nitrates andphosphates)
Lake ecosystemnutrient overload
and breakdown of chemical cycling
Stormwater
Biological Condition(Phosphorus)
Biological Condition(Nitrogen)
Impaired Rivers
Burton and Pitt (2002) Stormwater Effects Handbook
Impaired Lakes
Burton and Pitt (2002) Stormwater Effects Handbook
Biological Condition(Taxa)
Why should we care?• Drinking water
• Irrigation
• Contact (swimming, wading)
• Recreation (fishing, boating)
• Waste purification
• Aesthetics
• Ecosystem integrity
Friday, August 6, 2004
“U.S. beach closures hit 14-year high - Unsafe water caused by runoff, lack of funding, report says”
Credit: Center for Watershed Protection