Distribution of Earth’s
Water
The Oceans
Water covers about 75% of the Earth’s
surface
97% is salt water
3% is fresh water
only 1% of fresh water can be used
There are 4 major bodies of water:
Atlantic Ocean
Pacific Ocean
Indian Ocean
Arctic Ocean
Ice
- 76% of fresh water
- Most of Earth’s fresh water is locked in thick sheets
of ice near the North and South Poles.
- Icebergs – huge chunks of floating ice made of
fresh water.
Rivers and Lakes
– .34% of fresh water
– Very little fresh water but important
to people who live near them.
Groundwater
- 23% of fresh water (shallow and deep combined)
- Water fills the cracks and spaces in underground
soil and rock layers.
Surface Water
River Systems
a. Tributary – streams and smaller rivers that feed into a main
river
b. Watershed – land area that supplies water to a river system.
c. Divide – separates one watershed from another by a ridge of
land
Pond
a. Body of fresh, standing water
b. Smaller than lakes – sunlight reaches the bottom
c. Formed when water collects in hollows or low-lying areas
of land
d. Home too many animals including frogs, crayfish, sunfish,
water lilies, algae, etc.
Lakes
- Body of fresh water that no sunlight reaches the bottom
- Deep and big
- Formed two ways
Same as a pond
Powerful forces that shape Earth’s surface such as ice
depressions, crust movement or volcanoes
Wetlands – a land area that is covered with water during
part or all of the year.
– 3 types
• Marshes – grass covered by shallow water
• Swamps – flooded forests with trees – usually in warm,
humid climates
• Bogs – depression from ice sheets – usually in cold
climates
Water Underground
Movement
– Permeable – water runs through the ground
• Gravel
– Impermeable – water cannot pass through easily
• Clay
• Granite
Zones
Saturated – soil is totally
filled with water
Unsaturated – soil can
still accept water
Ground water
– Springs – ground water bubbles or flows out of
cracks in rock to Earth’s surface
– Aquifer – underground rock or sediment that
holds water
– Well – channel dug into an aquifer to provide a
supply of water
– Geyser – hot spring from which water periodically
erupts out
Using Freshwater Resources
How People Use Fresh Water
– Household purposes
– Industry
– Transportation
– Agriculture
• Irrigation – supplying water to areas of land to make
them suitable for growing crops
– Recreation
Conserving Water
Reduce
Recycle
Reuse
Pollution – addition of any substance that has a
negative effect on water or the living things
that depend on the water