Water CycleWater CycleWeather Dynamics UnitWeather Dynamics Unit

Science 10 Science 10

Mrs. S. Pipke-PainchaudMrs. S. Pipke-Painchaud

http://www.rspb.org/policy/waterwetlands/management/cycle.asp

http://ga.water.usgs.gov/edu/watercycle.html

The Water Cycle: http://www-k12.atmos.washington.edu/k12/pilot/water_cycle/grabber2.html

• Quotation:• “Water on earth is used over and over. The water cycle, the

continuous movement of water from ocean to air and land then back to the ocean in a cyclic pattern, is a central concept in meteorology. In the water cycle, the sun heats the Earth's surface water, causing that surface water to evaporate (gas). This water vapor then rises into the earth's atmosphere where it cools and condenses into liquid droplets. These droplets combine and grow until they become too heavy and fall to the earth as precipitation (liquid if rain, solid if snow).

• Water is temporarily stored in lakes, glaciers, underground, or living organisms. The water can move from these places by streams and rivers, returns to the oceans, is used by plants or animals or is evaporated directly back into the atmosphere.”– Source: University of Washington – Water- A Never Ending Story

• http://www-k12.atmos.washington.edu/k12/pilot/water_cycle/teacherpage.html

• Water vapour enters the atmosphere through transpiration, evaporation and sublimation.– Transpiration: the evaporation of water through the stomata in

the leaves.– Evaporation: changing from a liquid to a vapour (gas)– Sublimation: changing from a solid to a vapour (gas)– Deposition: reverse sublimation vapour to solid

• In the cool upper atmosphere, the water vapour condenses, forming clouds.

• Over time enough water collects to cause precipitation.– Falls over ground

• Absorb into the ground (percolation), runoff into nearby lakes streams, rivers or lakes (surface runoff).

• Some water percolates down to the bedrock where it becomes groundwater. It may eventually run back to lakes or other bodies of water.

– Some of the water in the soil moves up to the roots of the plants by capillarity.

Source: Biology 20 Duotang – Water Cycle

Stomate on the underside of a leaf:

~ Mike Morganhttp://www.microscopy-uk.net/mag/indexmag.html?http://www.microscopy-uk.net/mag/articles/stomata.html

Condensation: change from a vapour to a liquidhttp://2xup-ph.org/album/03/12/condensation.php

• Plants obtain water from the soil.

• Animals obtain water from eating plants, other animals or drinking it directly.

• When plants and animals die, their decomposing bodies release water back into the environment.

Source: Biology Duotang – Water Cycle

The Water CycleThe Water Cycle

• Consult the following websites to review the water cycle:– United States Environmental Protection Agency

(EPA) – Water Cycle Animation• http://www.epa.gov/globalwarming/kids/water_cycle_version

2.html• Quiz

– http://www.epa.gov/globalwarming/kids/quiz_water_cycle.html

– BBC Educational Resources – Water Cycle Animation• http://www.bbc.co.uk/schools/riversandcoasts/water_cycle/riv

ers/pg_02_flash.shtml– Earth Diagrams

• http://earthguide.ucsd.edu/earthguide/diagrams/watercycle/

• Dr. Art’s Guide To Planet Earth– Water Cycle

• Be sure to try each of the three activities (Watch me Cycle, Reservoirs, and Residence Time)

• http://www.planetguide.net/book/chapter_2/water_cycle.html

• UNESCO – World Day for Water– Description of the Hydrological Cycle

• http://www.unesco.org/science/waterday2000/Cycle.htm

• The World’s Water – Is There Enough?

• “Global Run-off per Capita Year Average– 1970 - 12.900 m3/person– 1995 - 7.600 m3/person

• Source: Assesment of Water Resources and Water Availability in the World; State Hydrological Institute, St. Petersburg, Russia, Prof. I. A. Shiklomanov, et al. 1996.” (World Day for Water)

Aral Sea – A Case of Over-Aral Sea – A Case of Over-exploitation of Water Resourcesexploitation of Water Resources

• Quoted from: - World Day for Water – The World’s Water – is there enough?”

• The problems of the Aral Sea provide a clear message about over-use of water resources. Fed by the flows of about 50 cubic kilometres of water a year from the rivers Amu Dar’ya and Syr Dar’ya, it used to be the world’s fourth largest inland body of water. Since 1960, much of the flow of these rivers has been diverted for irrigation of the cotton, rice and other crops. From that time the area of the sea has shrunk by almost 50 per cent and salinity has increased dramatically. The level has fallen by 15 metres, exposing large parts of the sea bed. The result has been catastrophic for the people living in the Aral Sea Basin.

• The fishing industry has been lost, and salts blown from the former sea bed are toxic to humans and detrimental to crops.

• Moreover, inefficient irrigation has caused waterlogging and salinization. These and other problems, such as water pollution from domestic and industrial wastes, are set against the background of an aquatic ecosystem which has been largely destroyed.

Aral Sea ImagesAral Sea Images

http://www.dfd.dlr.de/app/land/aralsee/chronology.html

The Aral Sea Homepage:

http://www.dfd.dlr.de/app/land/aralsee/

• View the animation and see the decrease in water.

The HydrosphereThe Hydrosphere

• Section 13.8 ~ Nelson Science 10 Textbook

– Include freshwater (2.5%) and saltwater (97.5%)– Freshwater (of the 3%):

• 87.3% - glaciers & polar ice caps• 12.3% - underground water• 0.4% - surface and atm water

– Of the 0.4%• 90% - lakes• 9% - atmosphere• 1% - rivers

– Source: Nelson Science 10 522

Canada & FreshwaterCanada & Freshwater

• We are very fortunate to live here.– We have 0.5% of the world population– We have 10% of the world’s freshwater supply!

• Did You Know?– Pacific Ocean:

• Largest ocean – 46% • Deepest ocean – 11 km deep in one place

– Arctic Ocean:• Smallest Ocean – 2.6%

• Nelson Science 10 522

Water TriviaWater Trivia

• USGS – • http://ct.water.usgs.gov/EDUCATION/trivia.htm

– CSREES – Florida Water Quality Program• http://waterquality.ifas.ufl.edu/Water%20primer/Tri

via/Trivia.htm

– Water Trivia:• http://www.sbvmwd.com/water%20conservation/w

atertrv.htm

Text Questions:Text Questions:

• Page 524 – 2,3,4,5,6,8

Resource Websites:Resource Websites:

• The Water Cycle• http://www.picadome.fcps.net/lab/currl/water_cycle

/default.htm

• University of Illinois – Hydrological Cycle

• http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/hyd/home.rxml

• UNESCO – World Day for Water – http://www.unesco.org/science/

waterday2000/general.htm