EARTH’S WATER RESOURCES
EARTH’S WATER RESOURCES
EARTH’S WATER RESOURCES
EARTH’S WATER RESOURCES
LAS VEGAS, NEVADA, USA• One of fastest growing major
cities in the United States (entire developed world)
• Las Vegas - located in center of Vegas Valley (desert region)
• Surrounded by Sierra Nevada and Spring Mountains
• Hot, windy & dry (38°C)• Mountains act as barrier from
moisture from Pacific• Dry (114 mm of precipitation in a
year - 216 clear days)
LAS VEGAS, NEVADA, USA
LAS VEGAS, NEVADA, USA• Vegas has enough natural water
(artesian spring) for 350,000 people
• Population is 1.95 million• 88% of Las Vegas water comes
from Lake Mead (at 43% capacity)
• Las Vegas will need to pump in water from other sources by 2010-11 water crisis US
• Lake Mead may be completed dry in 20 years Las Vegas grass
WORLD WATER RESOURCES
• Earth has 1376 million km3
• 97.4% in Oceans (1340.74 km3)
• 2.6% fresh water (36.26 km3)
• water
FRESH WATER RESOURCES• 1.8% glaciers & permanent
snow cover (24.87 km3)• 0.8% in ground water and
permafrost (10.85 km3)• 0.007% lakes, rivers & bogs
(1.10 km3)• 0.00072% H2O in
atmosphere (0.01 km3)
FRESH WATER RESOURCES• Under ideal circumstances there is
enough fresh water on the earth to support 20 billion
• Except 1) most F.W. exists in inaccessible
forms (polar glaciers & permafrost and vapour
2) Large reserves not available where demand for water is greatest (e.g. Canada - 60% of rivers drain north away from 90% of population
FRESH WATER RESOURCES3)Water pollution - 100s of
millions of people forced to rely on unsafe water
• 2.8 billion (40% of world) live with some shortage of fresh water
• 1.2 billion - severe water shortage
• 1.6 billion live in economic water shortage
• water
FRESH WATER RESOURCES• Some improvements since
1990 but still 1 billion people have no access to safe drinking water (1.6 billion have gained access)
Fresh Water Resources• Water use has more
than 2x the rate of pop for past century
• Water scarcity occurs when 75% of river flows are withdrawn
• 2.5 billion people living without proper sanitation (1 billion in Asia and 1/2 billion Sub-Saharan Africa
Fresh Water Resources• Water use has more than
2x the rate of pop for past century
• Water scarcity occurs when 75% of river flows are withdrawn
• 2.5 billion people living without proper sanitation (1 billion in Asia and 1/2 billion Sub-Saharan Africa)
Fresh Water Resources• 70% of pop without proper
sanitation live in rural areas
• In sub-Sahara Africa (21 countries) - 16% of poor and 79% of rich have access to sanitation
Fresh Water Resources• 70% of pop without proper
sanitation live in rural areas
• In sub-Sahara Africa (21 countries) - 16% of poor and 79% of rich have access to sanitation
Millennium Development Goals
Part of MDG’s to end poverty by 2015
• Goal #7 - Environmental Sustainability
• Target #3 - Halve the proportion of world population without sustainable access to safe drinking water and basic sanitation
Millennium Development Goals
• Diarrhea - 4 billion cases per year - 1.5 million deaths (most children under age of 5) - 88% of cases due to unsafe water, poor sanitation
• Trachoma - 5 million people visually impaired - infection rate could by 27% with improve water
• MDG7
Millennium Development Goals
• Schistosomiasis - 200 million infected - could be by 77% improved water and sanitation
• Intestinal worms - infect 1/3 of world pop - undernutrition caused by infections can lead to cognitive impairment, anemia or massive dysentery
Top Ten Sources of Fresh Water - Percentage of World
Total
Brazil - 14.9% Russia - 8.1% Canada - 6%United States - 5.6% Indonesia - 5.1%China - 5.1%Colombia - 3.9%Peru - 3.5%India - 3.5%DRC - 2.3%
• Nile