Water CycleWater Cycle

What is the water cycle?What is the water cycle?

• This is how water circulates through our environment

• Water changes from water to gas over and over again to complete the water cycle.

EvaporationEvaporation

• Water evaporates into the atmosphere from the ocean, lakes, etc.

• Evaporation = liquid gas

CondensationCondensation• When water vapor particles join together

to form a liquid and condense into clouds or dew.

• Condensation = gas liquid

PrecipitationPrecipitation

• Rain or snow that falls to the Earth

InfiltrationInfiltration

• The seeping in of water into soil or rocks through the cracks in the ground.

• Eventually, this water goes back into the lakes and rivers.

RunoffRunoff• Water that flows downslope on Earth’s

surface and may enter a stream, river, or lake.

• The rate of runoff is influenced by the angle of the slope, vegetation, rate of precipitation and soil composition.

• Water that doesn’t go through infiltration, goes through runoff.

RunoffRunoff

TranspirationTranspiration• When plants absorb the water and then

release it back into the atmosphere through evaporation

• Evaporation off of a plant

Water CycleWater Cycle

The Structure of HydrosphereThe Structure of Hydrosphere

• Oceans—96.5% of water found here

• Fresh water—3.5% of water found here

• Fresh water distribution:– Ice: 1.762%

– Groundwater: 1.7%

– Surface Fresh Water: 0.014%

– Atmosphere and soil: 0.002%

Understanding Where Your Water Is Understanding Where Your Water Is Located—Oceans and IceLocated—Oceans and Ice

• What bodies of water hold the largest amount of water?– Oceans—the largest bodies of water on Earth

(contain salt water only)• Features housing water as ICE

– Icebergs: a large piece of freshwater ice floating in open waters. **approx. 85% of icebergs are under the surface of the water.

– Glaciers: any large mass of ice that moves slowly over land formed by snow falling and compressing layer upon layer.

– *permanent snow areas also “house” water as ice

Fresh Water Locations—Surface Fresh Water Locations—Surface WaterWater

• What is the difference between a watershed and a river basin?– Both terms describe land that drains into a

river, stream or lake• River Basin: the term used to describe an

area that drains into a large river• Watershed: the term used to describe an

area that drains into a smaller river or stream

Fresh Water Locations—River Fresh Water Locations—River Basins and WatershedsBasins and Watersheds

• Larger river basins are made up of many interconnected watersheds– Example: Cape Fear and Neuse River Basins

are made of many small watersheds

• The water in a watershed runs to the lowest point—a river, stream, lake, or ocean

Fresh Water Locations—Rivers, Fresh Water Locations—Rivers, Streams, and LakesStreams, and Lakes

• What is a river?– A large channel along which water is continually

flowing down a slope—made of many streams that come together

• What is a stream?– A small channel along which water is continually

flowing down a slope—made of small gullies• What is a lake?

– A body of water of considerable size contained on a body of land

Fresh Water Locations--GroundwaterFresh Water Locations--Groundwater

• What is groundwater?– The water found in cracks and pores in sand,

gravel and rocks below the earth’s surface

• What is an aquifer?– A porous rock layer underground that is a

reservoir for water

What determines how far it What determines how far it goes?goes?

• Porosity: measure of a rock’s ability to hold a fluid.

• Permeability: a measure of the ease of flow of a fluid through a porous solid

AquifersAquifers

• porous rock layer which is capable of yielding useful supplies of water

• layers of sand or fractured rock in which the pore spaces or fractures are filled with water

Other Surface WatersOther Surface Waters

• What is a wetland?– An area where the water table is at, near or

above the land surface long enough during the year to support adapted plant growth

• What are the types of wetlands?– Swamps, bogs, and marshes

• Swamp: a wetland dominated by trees• Bogs: a wetland dominated by peat moss• Marshes: a wetland dominated by grasses