Processes
What process turns water vapor into liquid water?
condensation
How can water particles leave the atmosphere?
condensation or precipitation
Can humans change how much water there is?
No.
How much of Earth's total water is salt water?
97%
What is salinity?
variations in concentrations of salt
What process turns liquid water into water vapor?
evaporation
How can water particles go from the ocean to the atmosphere?
evaporation
Why is the demand for fresh water increasing worldwide?
Human populations are increasing
How much fresh water is available as "free water"?
less than 1%
The ocean currents are broken up by...
giant landmasses.
How does the sun drive the water cycle?
adding energy to the system for evaporation
What is groundwater, and how does it form?
Water stored beneath Earth's surface, filters down from the soil.
List two human large-scale activities that require water use.
Industry and agriculture
Most of the water humans can easily use come from.... and ....
lakes and rivers.
What causes the ocean to have different densities?
temperature and salinity
Why does water evaporate faster on a hot day than on a cold day?
more energy is available on a hot day.
What role do clouds play in the water cycle?
Hold liquid water in the atmosphere, collects until the particles are large enough to fall as precipitation.
What effect might human population increase have on the water cycle?
Increased removal of water, depletion of freshwater sources, increased competiton for water, altered water patterns, droughts, flooding
Groundwater can be stored in...
porous rock or aquifers
What are the driving forces of ocean currents?
winds, differences in water density, and tides
What is precipitation? Give two examples.
Water falling from clouds. Rain, sleet, snow, hail.
Why is the water cycle considered a “closed system”?
Almost no material comes to Earth from space, and no material is lost.
How might removing trees affect the water cycle?
reducing water vapor released by trees, decreased rainfall, increased runoff, flooding, droughts
If evaporation didn’t occur, what would happen to the water cycle?
the water cycle would essentially stop, as there would be no way for liquid water on Earth to enter the atmosphere as water vapor, leading to a lack of clouds, precipitation, and ultimately, a severe shortage of freshwater available on land.
Describe two patterns seen on the map of Earth's Main Boundary Currents.
1) Circular patterns in the oceans following landmasses 2) currents are not crossing the equator