the composition of the planet’s water the hydrologic cycle
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The Composition of the Planet’s Water
The Hydrologic Cycle
0 1000 1700 2500 6000 15000 70000
Data not available
Cubic meters per person per year
Water scarce Water stressed
Global Freshwater Availability
Physical Water Scarcity vs. Economic Water Scarcity
Region Average water availability (cubic meters/person)
Middle East and North Africa 500
Sub-Saharan Africa 1,000
Caribbean 2,466
Asia/Pacific 2,970
Europe 4,741
Latin America 7,200
North America (including Mexico) 13,401
Water Availability per region (2012)
Green, Blue, and Gray Water
Global Water Use
Water Consumption Per Capita
Virtual Water:All the water (green, blue, grey) used throughout the
process of production of each good
Product Virtual-water content (liters)
1 sheet of paper (80 g/m2) 101 tomato (70 g) 131 slice of bread (30 g) 401 orange (100 g) 501 apple (100 g) 701 glass of beer (250 ml) 751 glass of wine (125 ml) 1201 egg (40 g) 1351 glass of orange juice (200 ml) 1701 bag of potato crisps (200 g) 1851 glass of milk (200 ml) 2001 hamburger (150 g) 2,4001 cotton T-shirt 2,7001 pair of shoes (bovine leather) 8,000
Type of fuel
Amount of water needed in the extraction/production of 2 Million BTUs of energy
Natural Gas (conventional) 5 gallons
Unconventional natural gas (shale) 33 gallons
Oil (conventional) 32 gallons
Oil tar sands (mining) 616 gallons
Biofuel type 1 (irrigated corn) 35,616 gallons
Biofuel type 2 (irrigated soy) 100,591 gallons
Virtual water used in six types of fuels, for a round trip New York City- Washington D.C.
Calculate your own water footprint = direct water use + virtual water of all goods and serviceshttp://www.gracelinks.org/1408/water-footprint-calculator
The average person living in the US consumes about 2220 gallons of water a day: That’s 44 bathtubs each day. Diet makes a big difference: a vegetarian’ water footprint can be less than 50% of a meat eater’s footprint.
National Water Footprint for selected countries, in cubic meters per person per year (1997-2001)
Water-Energy Nexus
Trade in Virtual Water : Cotton
Transfers of virtual water through tradeVirtual-water balance per country
(billion cubic meters)
1,5 million people internally displaced because of the 2006-2011 drought
March 2011: Anti-Assad Revolution erupts
Water Scarcity and Conflicts: Syria
Two people, one land, one aquifer: Water and the Israeli-Palestinian conflict
Addressing Water Shortages
Increasing water supply? •Dams (dramatic ecological and social consequences).•Pumping aquifers (20% aquifers are already being mined beyond their rate of recharge, including the Upper Ganges Valley in India and Pakistan, the Nile Delta Region in Egypt, and the Central Valley in California).•Desalination: energy-intensive and costly.Dealination in California: $1800-$2800 per AFGroundwater: $375-$1100 per AFSurface water: $400-$800 per AF
•Water ConservationMicro-irrigation – reuse and recycle wastewaterCost of conservation (San Diego county): $150-$1000 per AF
•How to promote water efficiency?
Demand
Supply (MC)
Marginal Social Cost (MSC)
Price
Quantity of WaterQSQEQ*
PE
PS
P* A B C
Regulation by the market? The market price of water and
the problem of subsidies for large irrigators
Subsidies to irrigation lead to a consumption of Quantity Qs of waterQe would be the market equilibrium without subsidiesQ* would be the ecologically optimal quantity withdrawn
Average Monthly Water Bills in U.S. Cities
Pric
e pe
r U
nit
Quantity of Water Used
Uniform Rate Structure
Pric
e pe
r U
nit
Quantity of Water Used
Increasing Block Rate Structure
Pric
e pe
r U
nit
Quantity of Water Used
Decreasing Block Rate Structure
Pricing Structures
Increasing Bloc Rate Structure in U.S. Cities
Water Use Average Value per AF Median Value per AF Navigation $146 $10 Recreation/Wildlife Habitat $48 $5 Hydropower $25 $21 Thermoelectric Power $34 $29 Irrigation $75 $40 Industrial $282 $132 Domestic $194 $97
Marginal Value of Water in Various Uses (per acre-foot)
Markets of Water Rights for Major Users (irrigators, industries, cities)
• Water markets are in place in several countries, including Australia, Chile, South Africa, the United Kingdom, and the United States.
• In the US, Municipalities are the most common purchaser of water (mostly from irrigators), but transfers between irrigators are also common. About 17 percent of the water purchased is for environmental purposes, including purchases by municipalities and environmental organizations. => great potential for water markets to improve the environment
Water Management and Governance: What institutional frameworks for water conservation?• State control? Public services in developing countries have often proven inefficient
and corrupt• Privatization? Promoted by World Bank and IMF – but without appropriate regulation,
water companies can charge excessive rates and fail to address the needs of the poorest
The “Water War” in Cochabamba, Bolivia, 2000
The acequias of New Mexico are communal irrigation canals, a way to share water for agriculture in a dry land.
“Communities have relied on institutions resembling neither the state nor the market to govern some resource systems with reasonable degrees of success over long periods of time ” - Elinor Ostrom, in “Governing the Commons” (1990)
Re-creating Collective Systems for Management of the Commons?
Local Movements for Re-Municipalization of Water
180 cities and communities in 35 countries, including Buenos Aires, Johannesburg, Paris, Accra, Berlin, La Paz, Maputo and Kuala Lumpur, have all “re-municipalized” their water systems in the past 10 years.