Ch 9/10 Earth’s Water
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Transcript of Ch 9/10 Earth’s Water
Ch 9/10 Earth’s Water
Lesson 1
The Hydrosphere and the Water Cycle
Think About It…
Why is it that the water in your bottle could have been drunk
by George Washington?
Focus Question…
What is the structure and functioning of the
hydrosphere?
The Hydrosphere…A. The hydrosphere is…
• the water on and in Earth’s crust
B1. The percentage of water found in the oceans…• 97• We don’t call ourselves the
Blue Planet for nothing!
B2. The percentage of water contained by the landmasses…• 3
http://www.earthview.pair.com/earth300color.jpg
C. Of the Freshwater on Earth…
1. 90% is in the form of…• polar ice caps and
glaciers
2. Most of the remaining water is…• groundwater
3. Only a small fraction is in…• rivers, streams, and
lakeshttp://adventure.nationalgeographic.com/adventure/trips/family-trips/glacier-bay-alaska/
Alaska’s Glacier Bay
The World’s Water Supply…
Oceans – 97.2% - thousands of yearsIce caps and glaciers – 2.15% - tens of
thousands of yearsGroundwater - .31% - hundreds to
thousands of yearsLakes - .009% - tens of yearsAtmosphere - .001% - nine days!Rivers and streams - .0001% - two weeks
The Water Cycle…
a. oceans
b. groundwater 2. It returns to the surface and to the ocean
1. The Water Cycle…
Runoff…
1. Runoff is…• water flowing down slope along Earth’s
surface
http://myecoproject.org/wp-content/uploads/2009/02/stormwater.jpg
2. Four Factors that Affect Runoff…
a. Vegetation…
• Soils with no vegetation have more runoff.
2. Four Factors that Affect Runoff…
b. Rate of Precipitation…
• Heavy rain leads to more runoff (Water falls too quickly to soak into the ground)
http://luirig.altervista.org/cpm/albums/nrcs3/normal_1389-Runoff-from-a-heavy-rain-carries-topsoil-from-a-cr.jpg
2. Four Factors that Affect Runoff…
c. Soil Composition…… Soil with a lot of fine particles (like clay)
leads to more runoff (Clay prevents water from soaking in.)
2. Four Factors that Affect Runoff…
d. Slope…
• Steep slopes have more runoff.
• The steeper the slope, the faster the water flows.
http://secretagentworms.org/images/runoff2nrcs.jpg
Stream Systems…
1. If a sufficient supply of water develops, the water begins to flow more permanently in a channel and can become a stream.
2. A large stream is called a river and all its tributaries make up a river system.
The Rivers of North Carolina…
Watersheds and Divides…
3. A watershed is all of the land area whose water drains into a stream system.
http://dutchesswam.files.wordpress.com/2010/05/watershed-image-small.png
North Carolina Watersheds…
http://www.learnnc.org/lp/media/maps/nc/Watersheds-NC-map.jpg
Watersheds and Divides…
4. A divide is a high land area that separates one watershed from another.
• The Eastern Continental Divide is located in the Blue Ridge Mountains.
Divides of North America…
http://en.wikipedia.org/wiki/Eastern_Continental_Divide
Watersheds and Divides…
5. The watershed of the Mississippi River is the largest watershed in North America!
http://www.epa.gov/gmpo/lmrsbc/index.html
Lesson 2
Surface Water: Rivers
Think About It…
Why do rivers form?
Focus Question…
What is the structure and functioning of a river?
A. Stream Load and Velocity…
1. All the materials that the water in a stream carries is known as the stream’s load.
http://upload.wikimedia.org/wikipedia/commons/9/9c/Stream_Load.gif
A. Stream Load and Velocity…
Three ways in which a stream carries its load...
a. Material is carried in solution after it becomes dissolved in a stream’s water.
b. All particles small enough to be held up by the turbulence of a stream’s moving water are carried in suspension.
c. Sediments that are too large or heavy to be held up by turbulent water are transported as a stream’s bed load. (See next slide.)
A. Stream Load and Velocity…
2. Carrying capacity is the ability of a stream to…
• transport material
http://water.weather.gov/ahps2/images/hydrograph_photos/muri2/muri2_2.jpg
B. Floodplains…
1. When do floods occur?
• when water spills over the sides of a stream’s banks onto adjacent land
(Soccer fields were built on the flood plain of the Yadkin River in Davie County. Why?)
http://www.nowpublic.com/world/floodplain
B. Floodplains…
2. How are floods related to groundwater levels?
… It is more likely to flood when groundwater levels are high because…
… the aquifer is already full and can only hold so much water.
… the dotted line on the diagram represents the groundwater level. http://www.sciencedirect.com/science/article/pii/S004896970800380X
B. Floodplains…
3. What is a floodplain?… a broad, flat, fertile area extending out from a
stream’s banks that is covered with water during floods.
… It is not wise to build on a floodplain because it is prone to flooding!
B. Floodplains…
4. Which agency monitors potential flood conditions?
• The National Weather Service monitors changing weather conditions.
• USGS has established gauging station on more than 4400 streams in the USA!
http://pubs.usgs.gov/fs/2005/3113/images/Cropped_bridge.jpg
C. Stream Valleys…
1. As a stream actively erodes its path, it forms a V-shaped channel.a. The beginning of a
stream is called the headwaters. These are cold, oxygenated, and free of sediment.
b. V-shaped channels have steep sides.
c. The Grand Canyon is a V- shaped valley.
The Grand Canyon
http://media-3.web.britannica.com/eb-media/78/3078-004-9B8860F2.jpg
Formation of Stream Valleys…
http://www.indiana.edu/~geol116/week9/rivprof.jpgNext 3 slides
Stream Valleys…
2. A bend or curve in a stream channel is a -
• meander
The Yadkin River
http://www.wfae.org/wfae/images/Yadkin.jpg
The Cape Fear River
http://www.wilmingtonbeachrentals.com/2010/02/cape-fear-river-facts-pictures.html
Meandering Streams…
3. Water in a stream flows at different velocities…
a. Center – fastest
b. Bottom and sides – more slowly
c. Outside of a meander – fastest rate of flow
d. Inside of a meander – more slowly
Meandering Streams – A Diagram
Meandering Streams…
4. A blocked-off meander becomes an …• oxbow lake• We have our very
own oxbow lake in the Carolinas – in the Congaree National Park just outside of Columbia, SC.
http://www.daviddarling.info/images/oxbow_lake.jpg
Oxbow Lakes…
Oxbow Lakes in Alaskahttp://www.alaska-in-pictures.com/oxbow-lake-aerial-3405-pictures.htm
Oxbow Lake in the Amazon
http://muller.lbl.gov/travel_photos/AmazonWebPages/AmazonWebPages-Pages/Image1.html
Meandering Streams…
5. The end of a stream is called the mouth
… and is usually located at the ocean or another large body of water
http://carolinagreensense.com/uploaded_images/NIWB-731140.jpeg
(Yadkin)-PeeDee RiverA Bigger View!
Deposition of Sediment…
1. Streams that lose velocity also lose their ability to carry …• sediment
2. An alluvial fan is a fan-shaped deposit commonly found in mountains. Alluvial Fan in the Sonora Desert
http://practicalbio.blogspot.com/2011/09/sonoran-desert-soil-distributions.html
Deposition of Sediment…
3. A delta is a triangular deposit that forms where a stream enters a large body of water.
a. The city of New Orleans is on the Mississippi River Delta. The Mississippi River Delta –
picture taken by Landsat 7
http://earthasart.gsfc.nasa.gov/mississippi.html
Yadkin Riverkeeper Website…
The Yadkin Riverkeeper organization is a member of the international Waterkeeper organization. This alliance includes baykeepers, deltakeepers, riverkeepers, lakekeepers, etc.
http://www.yadkinriverkeeper.org/content/video-messages
Lesson 3
Lakes and Freshwater Wetlands
Think About It…
What is the biggest lake you have ever seen in person?
Focus Question…
Why are lakes and wetlands important?
A. Lakes…1. Some definitions…a. What is a lake?
o a depression in land that holds water
b. What determines where a lake can form?o the surface materials
c. What is a pond?o a small lake
d. What is a reservoir?o a manmade lake
http://en.wikipedia.org/wiki/High_Rock_Lake
High Rock Lake
http://www.city-data.com/picfilesv/picv23839.php
2. Origin of Lakes…Oxbow Lake… a meander gets cut off
Weston Lake (Oxbow) in Congaree National Park
The Great Salt Lake in Utah - the remains of a sea
http://www.americansouthwest.net/utah/salt_lake_desert/salt_l.html
Moraine-dammed Lake - glacial melt is dammed by a moraine
http://pubs.usgs.gov/of/2004/1216/i/i.html
Moraine-dammed Lake in Alaska
Kettle Lakes - Glacial melt in a depression created by the glacier
http://www.geo.msu.edu/geogmich/kettle_lakes.html
Kettle Lakes in Michigan
3. Lakes Undergo Change…
a. What maintains a lake’s water supply?o rain, runoff, and
groundwater
b. A lake will exist for a long time if…o it gets more water
than it loses
c. After a long time a lake will…o dry up and fill up!
The Aral Sea: Uzbekistan
http://earthobservatory.nasa.gov/IOTD/view.php?id=1396
3. Lakes Undergo Change…
d. Eutrophication is…o excess nutrients cause
the overgrowth of algae which die and decay and use up oxygen
e. The process of eutrophication can be sped up by…o over-fertilizing land
near a waterway
Fish kill in the Salton Sea, CA
Eutrophication in Australia
http://www.eoearth.org/article/Eutrophication
Eutrophication Explained…
https://commons.wikimedia.org/wiki/File:Scheme_eutrophication-is.svg
Eutrophication Explained (in English!)…
http://library.thinkquest.org/04oct/01590/pollution/culturaleutroph.jpg
C. Lakes Undergo Change…
f. Four things that can pollute lakes are…o animal wastes o phosphate
detergentso industrial toxinso untreated
sewage
B. Freshwater Wetlands…
1. A wetland is…o land that is
soaked with water
Three examples of wetlands are…
a. bogs
b. marshes
c. swamps
Boardwalk at Bethabara Park Our very own wetlands!
http://www.tommangan.net/twoheeldrive/index.php/2009/11/29/easy-hike-at-historic-bethabara-park/
a. Bogs…
I. A bog is a water-soaked area with poor drainage.
ii. Water in a bog comes from…o Precipitation (rain)
iii. The soil in a bog is acidic because…
o of the decaying moss – This slows bacterial growth which prevents nutrient recycling.http://water.epa.gov/type/wetlands/bog.cfm
A bog in Alabama
http://here4now.typepad.com/here4now/2011/05/weeks-bay-reserve.html
Bogs…
iv. Interesting plants that live in a bog are the…o Venus fly trapo Sun dewo Pitcher plantsV. These plants are
carnivorous because of the nutrient-poor soil of the bog. They must digest insects to obtain nitrogen.
http://www.duke.edu/~jspippen/plants/carnivorousplants.htm
Marshes…
i. A marsh is a water-soaked area at the mouth of streams.
ii. Fresh water marshes often form…o At the mouth of a
river
iii. Marsh grasses have shallow roots that …o anchor silt and mud
deposits in a delta. (Builds land!)
Brackish marsh near Wanchese, NC
http://www.duke.edu/~jspippen/vistas/outerbanks.htm
Marshes…
iv. Plants found in a marsh include…o Grasseso Reedso Sedgeso Rushes
Marsh with reeds and rushes - natural reserve near Ravenna,
Italy
Swamps…
i. A swamp is…o a low-lying area
near a stream
ii. Swamps may develop…o from marshes
that have filled in and support the growth of shrubs and trees.
Congaree National Park, SC
http://vogeltalksrving.com/wp-content/uploads/2011/12/Mosquito-meter.jpg
Water Lily in Bok Tower Gardens, Orlando, FL …
http://attractionsmagazine.com/blog/2012/09/14/water-lilies-seem-to-big-to-be-true-at-bok-tower-gardens/
Swamps…
iii. Trees that grow in a swamp include…o mangrove treeso cypress trees
Mangroves in Biscayne National Park, FL
Bald Cypress Trees in Florida
Swamps…
iv. If a swamp were to be buried under tons of sediment…
• COAL might form!
http://www.learner.org/courses/envsci/visual/visual.php?shortname=coal_formation
3. Environmental Issues…a. Two valuable functions of
wetlands include…o the filtering of
watero providing a habitat
for migrating birds and fish fry (fish babies!)
b. What percent of our wetlands were lost between the late 1700s to mid-1980s?o 50 %o Why were they filled
in? http://www.pwconserve.org/wildlife/birds/snowgoose.htm
Snow Geese in Prince William Sound
Three Ways to Preserve Wetlands…
EducationConservationRegulation
Lesson 4
The Movement, Storage, and Erosive Action of Groundwater
Think About It…
Does your family drink well water?
Focus Question…
How is groundwater stored and how does it move?
I. Groundwater Storage and Movement
A. Precipitation and Groundwater…1. Remember the water cycle?
a. Most water in the atmosphere comes from oceans!
b. Most precipitation that falls on land becomes groundwater.
2. Eventually groundwater will…… return to the ocean to complete the water cycle.
B. Groundwater Storage…
1a. The percentage of pore space in a material is called…
• porosity
1b. The types of soil that have -• highest porosity - well- sorted• lowest porosity – poorly-
sorted
2a. Groundwater is stored…• in the pore spaces of rocks
and sediments (See picture )http://core.ecu.edu/geology/woods/GWANSW2008_files/image002.jpg
Groundwater Storage…c. The zone of saturation is…
• the depth below Earth’s surface at which groundwater completely fills all the pores
d. The water table is ……the upper boundary of the zone of saturation
e. Figure 10-2: Groundwater Storage (p. 421)
Groundwater Storage…
f. The depth of the water table varies…
In swampy areas the water table is almost at Earth’s surface whereas in arid regions it is far beneath Earth’s surface
Green Swamp, FL
Groundwater Storage…
g. If the water table is high, it is more likely to flood. If the water table is low, it is less likely to flood.
h. The water table fluctuates with the seasons and weather conditions because…
• of its dependence on precipitation (rain) to recharge it
http://www.tulane.edu/~sanelson/images/chwattab.gif
Groundwater Movement…
1. What is permeability?• the ability of a material to let water pass
through it
a. What subsurface materials are permeable?• sand, sandstone, and gravel
b. What subsurface materials are impermeable?• clay, silt, and shale
c. Why is clay used to line ponds & landfills?• It is impermeable (our storm drainage pond)
Aquifer…
2. An aquifer is the underground storage area for water consisting of permeable rock layers.
3. An aquiclude is an impermeable layer above or below an aquifer.
Groundwater Movement…
6. aquifer
7.
8. aquiclude
Groundwater: A Music Video…
The Story of Groundwater!http://www.groundwater.org/kc/
groundwater_animation.html
Lesson 5
Groundwater Erosion and Deposition
Think About It…
Why do some homes in Florida get swallowed up by the ground?
Focus Question…
What are the unique features of caves?
A. Caves…
1. What is a cave?• A natural underground opening with a
connection to Earth’s surface
2. Which acid forms caves?• Carbonic acid (H2O + CO2 in the soil)
3. Which rock is eroded by this acid to form a cave?
• limestone
Caves of the USA…
http://giantcrystals.strahlen.org/america/lechuguilla.htm
Lechuguilla Cave, N. MexicoCarlsbad Caverns, N. Mexico
http://en.wikipedia.org/wiki/File:Witchs_Finger_Carlsbad_Caverns.jpg
Mammoth Cave, Kentucky
http://www.britannica.com/blogs/2011/07/dark-depths-mammoth-cave/
Mammoth Cave: A Closer Look…
http://images.travelpod.com/users/socks/1.1248576883.mammoth-cave-river-styx-tour-route.jpg
Cave Formations…
http://www.cr.nps.gov/history/online_books/orca/underworld/sec1b.htm
Karst Topography - Sinkholes…
6. What is a sinkhole?
• A depression in the ground caused by the collapse of a cave
• http://southeastsinkhole.com/
Karst Topography
7. Karst topography are limestone regions that have sinkholes, sinks, and sinking streams – named for an area in Croatia.
A aerial photograph of a classic Karst terrain north of Lewisburg, WV
http://www.virginiacaves.org/lok/ccvup56.htm
Karst Topography…
Karst Topography
http://www.mospeleo.org/ozark_caving/springs/sprkarst.htm
•Missouri
Hard Water…
9. Hard water is water that contains high concentrations of calcium, magnesiun, or iron.
• Common in limestone areas
• Causes deposits of calcium bicarbonate and can clog water pipes. (p. 247)
• More soap must be used
Lesson 6
Groundwater Erosion and Deposition
Think About It…
What forms a spring?
Focus Question…
What are the unique features of springs?
A. Springs…
1. Ground water discharges at…• Earth’s surface
2. These natural discharges of water are called…
• springs
3. Water may flow out of a rock when…• an aquifer and an aquiclude come in contact
Ponce De Leon Springs
http://www.eyekonic.net/gallery2/d/1232-2/Ponce_20De_20Leon_20Springs_202.jpg
Location of Springs:
B. Perched Water Table
http://www.physicalgeography.net/fundamentals/8m.html
A. Near HorizontalSedimentary Layers
C. Fault-blocked
D. Limestone Regions
Hot Springs…
4. The temperature of ground water is…• the same as the average annual temperature
5. Hot springs are…• springs which have temperatures higher than
the human body
6. Hot springs are so hot because…• the subsurface is still hot from relatively recent
igneous activity
• Picture on next slide
Hot Springs at Yellowstone N.P.
http://www.guideoftravels.com/wp-content/uploads/2011/09/Yellowstone-National-Park.jpg
Springs and Geysers…
7. Most hot springs in our country are found in the…
• western states
8. A geyser is an …• explosive spring
that erupts at regular intervals
Old Faithful Geyser Yellowstone NP
http://www.gogobot.com/old_faithful_geyser_and_upper-yellowstone_national_park-attraction
Wells…
9. A well is…• a hole dug to reach a reservoir of groundwater
10. A cone of depression is produced by…
• the over pumping of wells
11. Drawdown is…• the difference between the original water table
level and that of a pumped well
12. Recharge is…• when water from rain or runoff is added to an
aquifer
Wells…
http://pubs.usgs.gov/gip/gw_ruralhomeowner/gw_ruralhomeowner_new.html
Wells…
13. An artesian well flows from a deep, confined aquifer which contains water under pressure.
Lesson 7
Use, Abuse, and Conservation of Water Resources
I. Threats to Our Water Supply…1. Overuse
2. Subsidence (sinking land over an aquifer)
3. Pollution in groundwater (sewage, industrial waste, landfills, agriculture)
4. Chemicals (not filtered out by sediments; hard to remove from groundwater)
5. Salt (one of the major threats to groundwater supplies; esp. coastal areas)
6. Radon (generated by radioactive decay of uranium in rocks – esp. granite and shale)
Protection of Groundwater…
1. Identify and eliminate pollution sources.
2. Monitor pollution.
3. Pump groundwater to surface and treat it.
II. Water Use A. The Importance of Water
1. Four important uses of freshwater… Agriculture, transportation, recreation, drinking!
2. Water is indispensable for life on Earth because…
1. It exists as a liquid
2. It stores a lot of heat
3. It is the universal solvent
4. Solid water expands
A. The Importance of Water…
3. Eastern states get the most precipitation.
1. Eastern states - cooling, energy production, and manufacturing.
2. Western states - irrigation.
4. Withdrawal rates of freshwater are increasing each year because…
…our population is growing!
Western states use more water for growing their crops…
Use of Water in the USA…
http://fracfocus.org/sites/default/files/water-use-pie-chart.jpg
B. Managing Freshwater Resources
1. Dams are built to……control flooding downstream
and to manage freshwater resources
2. In the USA, 23% of all freshwater is obtained from…
… aquifers (groundwater)
… Florida, Hawaii, and Nebraska depend almost entirely on groundwater.
B. Managing Freshwater Resources
3. Drawdown causes…1. wells to go dry
2. streams to run low or go dry
3. shallow aquifers on the coast to get salty (This is called salt water intrusion)
4. Desalination is removing salt from seawater to make freshwater. It is not practical due to high costs. See next slide…
Saltwater Intrusion…
http://www.wrd.org/engineering/images/seawater-intrusion.gif
Desalination…
http://www.tampabaywater.org/tampa-bay-seawater-desalination-plant.aspx
III. Water Pollution…
A. Types of Pollution…
1. Point sources ……have a single point of
origin (often a piped discharge)
…Three examples include (but aren’t limited to)…
a. sewage
b. spills
c. industry
Drainage into the Ohio River
http://www.waterencyclopedia.com/Po-Re/Pollution-Sources-Point-and-Nonpoint.html
http://www.lakescientist.com/learn-about-lakes/water-quality/pollution.html
III. Water Pollution…A. Types of Pollution…
2. Nonpoint sources … … come from widely spread areas and cannot be identified and cleaned up as easily.
… Two examples include (but aren’t limited to)…a. pesticides and fertilizers from farms and yards
b. oil and gasoline from parking lots
http://oceanservice.noaa.gov/education/kits/pollution/media/pol04a_460.jpg
B. Clean up!
Surface water is more easily polluted than groundwater but easier to clean up.
http://www2.epa.gov/cleanups
C. Reducing Water Pollution…
1. The Safe Drinking Water Act (1974) was designed to …
… ensure our citizens have safe drinking water
… Our water does not always meet these standards.
2. The Clean Water Act (1972) was created to…
a. eliminate sources of water pollution
b. restore water quality (which it has done!)
IV. Water Conservation
A. Community Water Conservation1. Farmers can use irrigation techniques like
trickle irrigation to save water. http://www.tricklering.com/
2. Industries can use recycled or gray water to save water.
B. Personal Conservation: How can you and I conserve water in our homes and yards?
Lesson 7 Video Clip…
The Cycle of Insanity: The Real Story of Water http://www.rivernetwork.org/blog/7/2010/04/12/new-surfrider-video-
shows-%E2%80%98-real-story-water%E2%80%99