The Water Cycle
Processes in the Water Cycle
• The water cycle is made up of 5 processes
– Evaporation/transpiration- water vapor entering the
atmosphere (from large bodies or water or plants
– Condensation- when air cools down, it can’t hold all
the moisture so it forms liquid drops on surfaces
– Precipitation- when water droplets get too large and
fall out of clouds back to the Earth
– Runoff- water that flows back to the oceans over the
land
The Water Cycle
Where Freshwater is Found
• Atmosphere (water vapor)
• Streams/rivers
• Ponds/lakes
• Groundwater
• Glaciers and icebergs
Groundwater
• Makes up 25% of freshwater
• Found underground
• If water fills all the spaces in the rock-saturated
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zone
Permeable-water can pass easily through spaces
in rocks
Impermeable-water cannot pass through the
rocks spaces
Acquifer- a permeable layer of rock that is
saturated with water
Weathering and Erosion
• Erosion-the process that wears down and
carries away rock and soil
• Weathering-process where rocks are
chemically altered or physically broken
down into fragments
Erosion
• Ways that erosion can
take place
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Gravity
Movement of streams
Groundwater
Glaciers
Wind
Waves
Cliff eroded
Glacier erosion feature
Groundwater eroding land
Waves eroding base
Of cliff
Gravity’s effect
Wind erosion
Types of Weathering
-Mechanical
• Mechanical weathering- physically
breaking down rocks through
– Frost wedging- ice expands and cracks rocks
– Abrasion- when rocks scrape or grind against
each other
– Growth of plant roots- gets in between rocks
and cracks them
Wind eroding a hole
through a structure
Water gets into the spaces in a rock,
expands while it freezes and cuts
through a rock
Types of Weathering
-Chemical
• Chemical weathering-chemical reactions
dissolve the minerals in a rock or change
them into new minerals
• Water is the main agent of chemical
weathering
Chemical eroding of ancient buildings