Transcript Slide 1

Freshwater
Distribution of Water
Water source
Oceans, Seas, & Bays
Percent
of fresh
water
Percent
of total
water
--
96.5
Ice caps, Glaciers, & Permafrost
69.6
1.79
Groundwater
30.1
1.7
Lakes
0.26
0.013
Soil Moisture
0.05
0.001
Atmosphere
0.04
0.001
Wetlands, Swamps
0.03
0.0008
Rivers
0.006
0.0002
Biological Water
0.003
0.0001
Source: USGS
70% of fresh water on earth exists as ice
South pole – 2 miles deep
North pole – 15 feet deep
Melting = 200 ft sea level increase
+ 45 ft
- 375 ft
If all the atmospheric moisture fell to the earth
at once the sea level would rise only one inch
Available Freshwater
Groundwater
Lakes
Soils
Wetlands
Rivers
0.775%
0.8%
er
e
RiR
v eiv
Ri resr
ve s
rs
Fr
esE
Lhwar
Ic Fre i quatthe
e s
i
an h d r
w
Ic G d G a
e ro
anu n lacter
d dw ier
G a s
lac te
ie r
Li rs
Su
qu
rfa
id
Gc
roe Li
n qu
G uW
ro dawteid
Su u nd atrer
r w
Su fac ate
rfa e W r
c e La a t
Wk e er
at s
e
La r
At
ke
m
o
L
s
At p ak s
At m oshe eres
m ph
os e
ph re
acre-feetof
ofwater
water
acre-feet
acre-feet of water
Water
on on
Earth
Liquid
Water
onEarth
Earth
Freshwater
1E+15
3E+13
1E+13
9E+14
9E+12
3E+13
8E+14
8E+12
7E+14
7E+12
2E+13
6E+14
6E+12
5E+14
2E+13
5E+12
4E+14
4E+12
1E+13
3E+14
3E+12
2E+14
5E+12
2E+12
1E+14
1E+12
00 0
Resource
Resource
Resource
98% of readily available freshwater is in groundwater
Water Distribution
Location, Location
6 countries possess half of the world’s
total renewable freshwater supplies.
Brazil
Colombia
Russia
Canada
Indonesia
China
Water Availability and Location
South America:
3 of the 10 largest rivers
25% of fresh river water
5% of world population
Greenland: 8 million gallons/person/day
Alaska: 1 million gallons/person/day
Congo: 130,000 gallons/person/day
Gaza: 37 gallons/person/day
Australia is the driest continent, but has small population
Asia has 2/3 of world population, but 1/3 renewable water
Water Demand
The three major factors causing increasing water
demand over the past century
•population growth
•industrial development
•expansion of irrigated agriculture.
Agriculture accounted for most freshwater withdrawal in
developing economies in the past two decades
Population expected to grow to 9.3 billion by 2050
2 billion people will be “water scarce” (UNFPA, 2002)
Industry and Income
Country
Agriculture
Industry
High income
30%
59%
Middle income
74%
13%
Low income
87%
8%
Industrial use in China is expected to increase 5-fold
.
Agricultural Production
1% world energy
Food production has
grown with population
70% of all water used
Irrigated land expected to expand by 23% in 25 years
Overall Consumption
Irrigation for crops uses 65- 70 percent of fresh supplies
It takes over 528 gallons of water to produce
enough food for one person for one day
Over the past 30 years, the area of land under
irrigation has increased by about 30%.
Industry uses 20-25 percent of available freshwater
steel, computers, and raw materials for industrial products
annual industrial water use in China could grow from
52 billion tons to 269 billion tons (5X) within the next two decades
Domestic use accounts for about ten percent of water use
each person needs between 2 -3 gallons of water a day
for drinking, food preparation, and cooking
average consumption per person is five gallons a day (WHO, UNICEF),
but in the U.S., Canada, and Western Europe the total
consumption rises dramatically (>50 gal/day)
Supply and Demand
Turning to Groundwater
Turning to Groundwater Use
Local, On-demand Availability, Drought Resistance, Good Quality
Heavy investment in groundwater exploration
50% of the world’s drinking water
40% of industrial water
20% of agricultural water
1.2 billion urban citizens worldwide depend on groundwater
Groundwater Use
Fastest growing countries
India
China
Pakistan
½ the world’s
total agricultural
groundwater use
In India, 80% of domestic supply and 70%
of agricultural supply is from groundwater
Growing Pains
This part of China is mostly flat
and the soil, replenished by silt
carried down by the Yellow River,
is well-suited to agriculture
Shallow sand, gravel, rock
North China Plain
½ China’s wheat, 1/3 corn
Shallow aquifer largely depleted (renewable)
99,900 wells were abandoned
Shift to Deep fossil aquifer (non-renewable)
Agricultural well depths can exceed 1000 feet ($)
Municipal well depths can exceed 3000 feet
Aquifer Levels dropping 3 ft/year
China’s grain production has fallen from its historical
peak of 392 million tons in 1998 to an estimated 358
million tons in 2005 (34 million tons-8%)
China largely covered the drop-off in production by
drawing down its once vast stocks until 2004, at
which point it imported 7 million tons of grain.
India
Population 1,132,446,000
21 million wells
water table is falling by 6 meters (20 feet) per year
falling water tables have dried up 95 percent
of the wells owned by small farmers
drilling 3000ft to reach water
agriculture is rain-fed and drinking water is trucked in
Pakistan
Punjab
Quetta
Pakistan is growing by 3 million people per year
In the Punjab plain, the drop in water tables appears to be similar to that in India.
In the province of Baluchistan, water tables are falling by 11 feet per year.
within 15 years Quetta will run out of water if the current consumption rate continues
Israel
Cenomanian-Turonian Mountain Aquifer
Besor
highly permeable
recharged from the West Bank
Coastal Aquifer
Width between 3 and 20 km
depth to groundwater 60 m to 8 m
chief resource of water for Gaza
Besor
Negev
Gaza has the lowest per capital
water availability in the world .
80-100 sites lack infrastructure and mitigation measures
Saudi Arabia Disi Conveyance Project
al-Disi aquifer
Sandstone aquifer not subject to recharge
Partly in Jordan
1984 Saudi national survey reported
fossil water reserves at 462 billion tons
Wheat on 2.5 million acres of desert
½ has been depleted
irrigated agriculture could continue for perhaps a few decades
The Sahara: Libya
1953
Nubian Sandstone Aquifer
“fossil” water
Formed 145.5 to 65.5 million years ago
two million square kilometers
world's largest fossil-water reserve
equivalent to the flow of 200 years
of water in the Nile River
located near the center of the world's largest continuous stretch of desert
The Great Man-Made River Project
the largest underground network
of pipes in the world
1300 wells more than 500 m deep
10,000km³
6,500,000 m³ water/day
4,800km³
Tripoli, Benghazi, Sirt
20,000km³
4 major basins
Water is 1/10 cost
Of desalinization
United States
Wettest
United States
Rhode Island
Florida
Land (mi2)
3,618,770
Water (mi2)
% water
79,481
2.2%
1,545
500.6
32.4%
65,975
11,808
17.9%
North Carolina, Maine, Louisiana, Minnesota, Massachusetts
Driest?
New Mexico
121,593
243
0.2%
Arizona
114,000
364
0.32%
24,232
145
0.6%
West Virginia
Surface water 79%
Texas
California
Idaho
Illinois
Groundwater 21%
California
Texas
Nebraska
Arkansas
Groundwater and Surface Water Use
#1 irrigation
#2 public Supply
#1 power generation
#2 irrigation
Groundwater
Surface water
Surface Water
Groundwater
Agriculture and the Ogallala Aquifer
Irrigation
1930s
1970s
600 wells
200,000 wells
¾ of wheat traded
on the world market
Slowly replenished:
Water tables have fallen
By up to 100 ft
5 – 25”/yr Rainfall
Pumping has declined by ½; new wells banned
irrigated
Below is a link for a story on NPR
http://www.npr.org/templates/story/story.php?storyId=12595774
Surface Water
Groundwater
Summary
Surface water 79% of withdrawals
Ground water 21% of withdrawals
#1 use of groundwater is for irrigation
#1 use of surface water is for power generation
Both ground and surface water withdrawals peaked in 1980
Texas uses the greatest amount of surface water
California uses the greatest amount of groundwater