global science: The Water Cycle

a) Once the sun heats a body of water such as an ocean, lake, or river the water evaporates back into the air, once that happens the water vapor condenses and form into clouds, once enough water condenses the droplets become heavy and turn into rain, snow, sleet, hail and so on. Then the cycle repeats again and again and again.

"Evaporation"- is when a liquid (water) changes into a state of gas and the water became water vapor.
"Transpiration"- is the process of evaporation through plant leaves which adds to the water vapor in the air.
"Condensation"- happens when gas changes to a liquid and the temperature of a vapor decreases. (opposite of evaporation).
'Precipitation"- water released from clouds. (such as rain, snow, or hail).
"Infiltration"- Water is filtered out. (cleaned)
"Surface runoff"- The water returns back to the oceans or lakes.
"Groundwater"- the underground movement of water.
"Absorption"- when water (rain,sleet,snow) is absorbed into the ground.

http://www.angelfire.com/nj/PflommScience/H20Cycle.htm
http://ga.water.usgs.gov/edu/watercycle.html

b) River water always flows downhill. Groundwater (aquifer) "moves sideways--but still downhill very slowly" underground. http://chamisa.freeshell.org/flow.htm
Water in the wetlands is always just still water that's basically just flood water that never dries up due to all the rain, but floods often. Lake water is also very still water that can also flood due to heavy rains, freeze and turn into ice at 32 degrees Fahrenheit or 0 degrees Celsius. Lake water is also sometimes water that rivers flow into, but that's based on the location of the river or lake. http://ga.water.usgs.gov/edu/watercycle.html

c) There are two types of rivers and streams, White water ("lightly acidic to neutral pH 6.3-7.0") and black water rivers ("pH between 3.5-6"). http://rainforests.mongabay.com/0602.htm. The black water rivers are the considerably the cleanest waters in the world. River erosion is the "gradual removal of rock material from the river banks and bed". http://library.thinkquest.org/20035/river.htm