Fresh Water Resources
Water - Basic Knowledge
Made up of 2 hydrogen and one oxygen
We can live without food for 50-60 days, but we can only live without water for 1-2 days (3 at most) Water resources are scarce
Life without water is why we don't live on mars
Describes the continuous movement and distribution of water on, above, and below earth's surface By changing its state, water moves among great global reservoirs 3 stages: gas, liquid, solid (ice)
When solid, it expands to a crystalized structure that's less dense than liquid water, causing it to float
Global Flux: 577,000km3 of water moves annually
Inputs = outputs
By looking at three global states
Precipitation(to oceans and continents)
| Precipitation(from atmosphere)
| Evaporation(to atmosphere)
| Evaporation(from ocean and continents)
| Run off (to oceans)
| Run off (from continents)
How much water moves between the stores?
Residence time = how long water stays in a store
Ocean: 3200 years
Deep groundwater: 10,000 years
Atmosphere: 9 days
What do we use water for?
….pretty much everything
How much water do we have?
Too much water
After winning a football game?
Some people in the least developed countries have to carry water for a couple miles to their homes Droughts
Save water, drink beer?
Maybe not, it can take 60-100L of water to make 1L of beer
By 2025, 3 billion people will have water stress of shortages
Availability of fresh water
Availability of clean, fresh water
Distribution of this
THERE IS NO ALTERNATIVE FOR FRESH WATER
Poor vs rich countries
Case Study: Mexico City
Located in the central part of the trans-Mexican volcanic belt About 7,500km2
Basin altitude: 2,200m about sea level...
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