Water is constantly moving through the water cycle on Earth. It falls as precipitation, runs across the surface as runoff, collects in surface water bodies or infiltrates underground as groundwater. Water evaporates from plant leaves, soil, and surface water before condensing in the atmosphere and falling again as precipitation, continuing the cycle. Most water on Earth is salty ocean water, while freshwater is found in the atmosphere, on land and underground. Humans rely on and impact the water cycle through activities like agriculture, industry, and domestic use. Conservation efforts can help reduce human water usage.

1. Hydrology
Water on Earth
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2. Water is constantly
moving through the
components of the
water cycle.
Precipitation: water that falls to the earth in the
form of ice, rain, snow, sleet, hail, etc.
Runoff: the process whereby water that falls to
earth moves across the surface of the earth and
eventually into bodies of water
https://upload.wikimedia.org/wikipedia/commons/c/c1/Precipitation_by_type.png
https://upload.wikimedia.org/wikipedia/commons/thumb/2/2b/View_of_urban_runoff_discharging_to_coastal_waters.jpg/200px-

3. https://upload.wikimedia.org/wikipedia/commons/b/b1/Groundwaterimage.jpg Surface water: water that exists on the surface of the earth such as
rivers, lakes, streams oceans, etc.
Ground water: water found underground (this water can be found in
spaces in the soil and between rocks).

4. Evapotranspiration
Transpiration: the process in the leaves of
plants that releases water in the form of
vapor (gas) into the atmosphere.
Evaporation: the process whereby a
substance changes from a liquid to a gas
https://lemondeetnous.cafe-sciences.org/wp-
content/uploads/sites/4/2016/04/evapotranspiration-300x248.gif
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https://images.pexels.com/photos/38435/leaf-rain-coffee-water-
38435.jpeg?auto=compress&cs=tinysrgb&fit=crop&h=627&w=1200

5. Condensation: the
process whereby a substance
changes from a gas to a liquid
Percolation/Infiltration:
the movement of water through the soil as water
falls onto the earth. This leads to the recharge of
groundwater
https://upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Condensation_on_water_bottle.jpg/1200px-
Condensation_on_water_bottle.jpg
https://upload.wikimedia.org/wikipedia/commons/thumb/e/e2/Stormwater_Management_with_trees.webm/1280px--Stormwater_Management_with_trees.webm.jpg

6. The water
cycle
https://upload.wikimedia.org/wikipedia/commons/thumb/b/b1/Diagram_of_the_Water_Cycle.jpg/1200px-Diagram_of_the_Water_Cycle.jpg

7. Where is freshwater
found?
In the atmosphere as rain, clouds, snow etc.
On Earth’s surface in rivers, lakes and oceans
Below the surface as groundwater in aquifers
and underground rivers
http://www.thegeographeronline.net/uploads/2/6/6/2/26629356/8167998_orig.jpg?412

8. Wetlands
• Land that is covered with water much of the
year is called wetland.
• Estuaries are wetlands.
https://www.goodfreephotos.com/albums/other-landscapes/wetlands-
landscape-under-the-clouds.jpg

9. Most of the
water on Earth
is salty
Oceans hold 97.5% of the
earths supply of water.
https://c1.staticflickr.com/1/607/31520427614_ddb8a4c9f7_n.jpg

10. Ocean currents
• The movement of the ocean currents is affected by tides, winds, and
temperature as well as the level of salt concentration in a given area
(salinity).
https://upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Circulation_of_Ocean_Currents_Ar
ound_the_Western_Antarctic_Ice_Shelves.ogv/300px--
Circulation_of_Ocean_Currents_Around_the_Western_Antarctic_Ice_Shelves.ogv.jpg
http://astronomyonline.org/SolarSystem/Images/Earth_Moon/OceanCurrent.jpg http://www.thegeographeronline.net/uploads/2/6/6/2/26629356/4648314_orig.jpg

11. What is brackish water?
Brackish water is a mixture of freshwater from rivers
and streams with saltwater from the ocean.
Brackish water is found in estuaries and any wetland
that has a mixture of salty sea water and fresh water.
https://wikiislam.net/wiki/images/a/a1/Estuary.jpg
https://santosasandyputra.files.wordpress.com/2015/12/estuary.jpg?w=1000

12. What is groundwater?
Groundwater is water that enters the ground as rain
or other precipitation infiltrates or percolates down
from the surface and collects between rocks and in
soil.
We access groundwater by drilling wells into the
water table and pumping out the water.
https://s3-us-west-2.amazonaws.com/candimgs/Mi8WsV/f-
d62fa713af72548f922d754148b3c962d1d070e90a9f2069c4bcae0a3IMAGE_THUMB_POSTCARDIMAGE_THUMB_POSTCARD.1
https://c1.staticflickr.com/1/461/31551458883_75b534e3f4_z.jpg

13. Humans use water
• cooking
• irrigation for agriculture
• bathing
http://www.groundreport.com/wp-
content/uploads/2016/05/Pot_irrigation_by_On-line_drippers.jpg
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gj5Lb2Q1Pic/WtTAVVsfODI/AAAAAAABy1Y/YjGWI1jwdh48wG-
zfXOnxkyV6XsX60YxACLcBGAs/s1600/10.jpg
https://farm3.staticflickr.com/2131/2347718246_9066990814_z.jpg

14. cleaning wastewater
• Wastewater treatment involves
collecting water from houses, businesses
and outdoor sewer drains at a
wastewater treatment plant. There large
particles are filtered out. Then the water
is disinfected by UV, chlorine, or ozone.
The water may be sent to be stored in a
reservoir to await reuse, or it may be
released into a river. When the water is
needed again, it is treated by removing
solids, and any pollutants. When it is
clean and safe to drink, it is sent through
pipes back to the municipal water system
and from there into homes and
businesses.
https://scioly.org/wiki/images/thumb/3/35/Wastewater_treatment.jpg/550px-Wastewater_treatment.jpgeg

15. The impact of agriculture on our
water supply
Agriculture is the largest user of our
water supply. Farmers use
groundwater to irrigate crops, which
can lead to aquifer depletion.
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D_TINY%2BIMAGE_THUMB_POSTCARD_TINY.1

16. Positive effects of hydroelectric dams
a. no emissions
b. renewable
Negative effects of hydroelectric dams
a. cause loss of habitat for the plants, birds and animals displaced by the
reservoir
b. makes less water for irrigation
https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/2011-06-07_17-17-11_996.jpg/1200px-2011-06-07_17-17-
11_996.jpg
https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/2011-06-07_17-17-11_996.jpg/1200px-2011-06-07_17-17-11_996.jpg

17. We can reduce our water use
a. install low-flow toilets and
shower heads
b. wash full loads of laundry and
dishes
c. use drip irrigation for
agriculture and rain barrels for home
irrigation
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