The Water Cycle Classwork
Name: _________________________
6th Grade PSI
1. Is water ever destroyed? Explain your answer.
2. True or False: The water we drink was around during the time of the dinosaurs.
Explain your answer.
3. What powers the water cycle? Explain two ways in which this energy source
causes changes to water within the cycle.
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The Roles of Water
The Water Cycle Homework
Name: _________________________
6th Grade PSI
4. True or False: The water cycle always follows the same pattern.
5. We cannot see evaporation occurring because water vapor is invisible. How can
we tell it is happening?
6. Water storage is an important part of the water cycle and our daily lives, where
do you observe water storage?
7. What might happen if the water cycle stopped?
8. We know the sun powers the water cycle but what powers the water cycle on
cloudy days?
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The Roles of Water
States of Matter in the Water Cycle
Classwork #1
Name: _____________________
6th Grade PSI
9. What is the opposite of evaporation? How do these two processes differ?
10. Describe how water can go through all the states of matter within the water cycle.
11. During what processes of the water cycle does a gas turn into a liquid?
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6th Grade PSI
The Roles of Water
States of Matter in the Water Cycle
Classwork #2
Name: _____________________
6th Grade PSI
From Toilet to Tap
Written by Stuart Thornton
October 21, 2010
Holding a plastic cup within the Orange County Water District’s Groundwater Replenishment
System (GWRS), program manager Shivaji Deshmukh announces a fact that might make some
people’s stomachs turn.
“An hour and a half ago, this was treated sewage,” he says. “A day ago, it was raw sewage.”
Having complete faith in the project and its end result, Deshmukh then downs the water without
blinking.
An ingenious method to fight California’s water shortage, the GWRS takes an unlikely
resource—sewage flushed down the toilets in Southern California’s Orange County—and
transforms it into drinking water that exceeds all state and federal drinking water standards.
Before taking the gulp of refreshing purified water, Deshmukh led me on tour of the facility,
which took about an hour, the approximate amount of time it takes the treated sewer water to
pass through three processes before becoming drinkable. Costing $480 million to construct, the
state-of-the-art water purification project has been up and running since January 2008.
The Groundwater Replenishment System is in an ideal location: just feet away from the Orange
County Sanitation District (OCSD), where the sewage from north and central Orange County is
treated. Every day, OCSD sends a third of their water over to the GWRS through a half-mile
long, 96-inch pipe. Orange County Sanitation District public affairs manager Michael Gold
explains the kind of water his neighboring facility receives: “When it comes in [to the OCSD], it’s
dirty,” he says. “It’s smelly. It’s full of viruses and junk. As it comes out of our plant, it looks
clean, but it’s not clean enough to swim and bathe in.”
Currently, OCSD sends about 70 million gallons of treated sewer water over to the GWRS every
day. Gold says that amount of water is roughly enough to fill up nearby Anaheim Stadium, home
to Major League Baseball’s Los Angeles Angels of Anaheim.
Three Processes
After OCSD sends treated water to the GWRS, it undergoes three processes to make it
drinkable: microfiltration, reverse osmosis, and ultraviolet disinfection.
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The first process is microfiltration. Deshmukh said this gets rid of bacteria, protozoa, and
suspended solids in the liquid by pushing it through a series of fiber membranes filled with tiny,
hollow tubes. He compared it to drinking iced soda through a straw. The pollutants are like the
ice, which is too large to be drawn up through the straw.
The water is propelled through the microfiltration membranes with giant, 600-horsepower
engines. Following microfiltration, the water sits in a large holding tank shaped like a rocket
ship.
Standing outside a sleek, modern building that resembles an airplane hangar, Deshmukh
looked toward the structure, which was marked with large lettering: Reverse Osmosis.
“This R.O. plant is one of the biggest in the world,” Deshmukh said.
Inside, the facility looks like a warehouse filled with stacks of plastic pipes.
“The water we get here has been microfiltered, but now we have to take the organics, the
pharmaceuticals, the viruses and salts out of the water,” Deshmukh said.
During reverse osmosis, specially made plastic sheets allow the passage of water while harmful
material as small as a molecule is separated out. “This is the heart of the treatment process,”
Deshmukh explained. “This allows us to make the water potable.”
In reverse osmosis, the water is pushed through the plastic sheets by 1,000-horsepower
engines. The program manager insists that the energy used in treating the water is worthwhile
when compared to other methods of supplying Orange County with water. One popular method
is shipping water from northern California.
“Reverse osmosis uses a lot of energy, but when you compare it to pumping water over a
mountain range [the Sierra Nevada], it’s less,” he said.
After Deshmukh taught me about the reverse osmosis process, we stepped outside into the
Orange County sun and walked towards the final stage the former sewer water had to be put
through. We stopped at a series of steel cylinders that are filled with ultraviolet light bulbs.
Ultraviolet disinfection destroys any of the water’s remaining viruses.
“This is the last step,” Deshmukh said. “After this, we actually add minerals back to the water.”
Aquifers
It’s here where Deshmukh and I tip back our plastic cups filled with the newly treated water and
drink in a liquid that may have been swirling around a toilet bowl just a day ago. But this water
actually has months to go before it will flow out of any of Orange County’s taps.
Half of the water treated by GWRS is injected into Orange County’s seawater barrier. The
barrier, a series of wells that function like a dam, helps keep the region’s aquifers, or
underground freshwater supply, from being overtaken by seawater from the nearby Pacific
Ocean.
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The Roles of Water
The other half of the water is pumped thirteen and a half miles up into Anaheim, where it is
discharged into several lakes. From there, it joins the region’s rainwater and settles into aquifers
as groundwater. In approximately six months, the groundwater is chlorinated by the cities of
Orange County and sent to taps for personal and business use.
Currently, Orange County Water District treats 70 million gallons of water every day. This
amount of high-quality water can meet the annual water needs of 500,000 people.
In addition to creating a renewable source of fresh water for the area’s growing population,
another benefit is that the GWRS reduces the amount of treated wastewater discharged in the
Pacific Ocean.
Though the initial idea of drinking reclaimed water might make some stomachs turn, the
success of Orange County’s Groundwater Replenishment System has caused a turn in
California’s thinking about the idea of transforming sewer water into drinking water. This change
has resulted in a series of proposals for similar facilities across the state.
Questions:
1. What was the purpose of this project? Why was the water treatment plant in the
article necessary?
2. Fill in the table below with a summary of each step of the water filtration process:
Microfiltration
Reverse
Osmosis
Ultraviolet
Disinfection
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The Roles of Water
3. Define the term aquifer. Why are aquifers important to the communities of
Orange County?
4. Provide three benefits to Orange County’s Groundwater Replenishment System:
a.
b.
c.
5. Water used for sanitation naturally becomes drinkable again as it travels through
the water cycle. Provide a detailed example of the steps this polluted water
could take to move through the water cycle and become clean again.
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The Roles of Water
States of Matter in the Water Cycle Homework
Name: ______________________
6th Grade PSI
12. You have learned about the textbook example of the water cycle. What are some
sub-cycles that exist?
13. Is it possible for water to become ‘stuck’ in a step of the water cycle?
14. During what processes of the water cycle does a liquid turn into a gas?
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6th Grade PSI
The Roles of Water
Forces of the Water Cycle Classwork #1
Name: ______________________
6th Grade PSI
15. What are the driving forces behind the water cycle?
16. What causes the oceans in polar regions to be cooler than oceans near the
equator?
17. The Coriolis Effect causes air currents to veer off course. What other impacts
might the Coriolis Effect have?
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6th Grade PSI
The Roles of Water
Forces of the Water Cycle Classwork #2
Name: ______________________
6th Grade PSI
Warming Waters
Written by Stuart Thornton
November 4, 2010
From the end of a pier jutting into Maryland’s Patuxent River, scientists at the Chesapeake
Biological Laboratory have determined that the region’s water temperatures are warming.
According to David Secor, a professor from the University of Maryland Center for Environmental
Science who works at the facility, the surface waters at the end of the pier have increased 3
degrees Fahrenheit since people began collecting data from the site in 1938.
Secor believes if little action is taken to slow global warming, the Chesapeake Bay could have
summer water temperatures comparable to Florida’s by the year 2100. Global warming is the
increase in the average temperature of the Earth’s air and oceans. The release of carbon
emissions into the atmosphere, mostly through industrial agriculture and burning fossil fuels,
probably contributes to global warming.
“If we do nothing—which is probably the simplest way to think about this—in 50 year’s time, we
are looking at at least a 3-degree Fahrenheit rise,” he says. “In 80 years time we could be
looking at a 6- to 8-degree Fahrenheit change.”
The Chesapeake Bay is an estuary off the Atlantic Ocean that stretches north into the states of
Virginia and Maryland and supports a variety of animal and plant species. More than 100 rivers
and streams from New York, Delaware, Pennsylvania, and West Virginia flow into the bay.
The plants and animals of the Chesapeake Bay have supported people since the first European
settlers arrived in the area more than 500 years ago. Oysters, fish, crabs, and wild rice were
part of the diet of the Powhatan, the Native Americans of the region. Chesapeake Bay still
produces more fish and shellfish than any other estuary in the United States. The blue crab, the
“state crustacean” of Maryland, is the most important fishery in the area.
Secor admits at this time he can only predict what might happen to the region’s ecology and
economy as the bay’s temperatures continue to climb. He thinks that climate change might
cause declines in species that are already stressed by disease and poor water quality.
Hot Water for Fishes and Plants
Secor says he suspects that Atlantic sturgeon and shortnose sturgeon will be affected by the
changes in the Chesapeake Bay. Sturgeon are huge fish, native to most rivers that feed the
Chesapeake Bay, including the James and the Susquehanna rivers. Sturgeon, a cold-water fish
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The Roles of Water
also native to Russia, are mostly harvested for their eggs, or caviar. Sturgeon are a benthic
species, meaning they live near the bottom of rivers.
Sturgeon are particularly sensitive to pollution. Runoff from farms and industry, as well as
overfishing, have threatened sturgeon populations in the Chesapeake Bay region.
“The combination of warm water and maybe frequent droughts, which are in the offing in the
future, could be the final nail in the coffin for species like sturgeon,” Secor says.
Secor also suspects that fish that thrive in cooler waters, including shad and striped bass, could
experience decreases in population brought about by a warmer climate.
“These species are already very stressed by water quality, by watershed development, by
impervious surfaces, by dams,” he says. “A stress like warming could produce a threshold
condition that causes very rapid declines in these species.”
According to Bill Dennison, the vice president for science application at the University of
Maryland Center for Environmental Science, the Chesapeake Bay’s rising water temperatures
could also change the makeup of the region’s plant communities. He cites an unusually warm
summer in 2005 that caused a mass die-off of eelgrass, a marine plant that is commonly found
along the mouths of tributaries that flow into the bay from Virginia.
If eelgrass were to die out in the Chesapeake Bay due to warming water temperatures, its
disappearance would affect other species in the region.
“Blue crabs and peeler crabs go into the grass to molt, so when they lose that protection they
are more susceptible to predation,” Dennison says.
According to Secor, increasing water temperatures in the bay can also cause species there,
including striped bass, shad and river herring, to misread environmental cues.
“These species migrate into the Chesapeake Bay according to certain reproduction and feeding
schedules,” he says. “With warming, those schedules can get miscued due to environmental
conditions.”
Reinventing Ecosystems
At this point, Secor admits he doesn’t know how the Chesapeake Bay will change as its waters
warm.
“There’s a lot of discussion about what is the ecosystem [is] going to look like,” he says. “We
just can’t say we are going to look just like a South Carolina estuary or a North Carolina estuary
or something like that. What we will be doing is kind of reinventing these systems. There will be
some species that can adapt to these trends most assuredly, and then others that will be
colonizing into the Chesapeake.”
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6th Grade PSI
The Roles of Water
Questions:
1. Define global warming. What impact is this having on the water of the
Chesapeake Bay?
2. What impact does rising water temperatures have on the native plants and
animals in the region? Provide at least 2 examples from the reading.
3. The Sun is one of the driving forces of the water cycle. Besides an increase in
water temperatures, what other effects could this heat increase have on the
water cycle?
4. Other areas of the world are experiencing temperature changes that are similar
to that of the Chesapeake Bay. Some scientists believe that this change may be
the result of an increase in carbon dioxide (CO2) production. Carbon Dioxide
production is directly related to how much energy we use and how many fossil
fuels (gas, oil, coal, etc) are burned.
What are two ways that individuals can help limit the amount of carbon dioxide
that is being produced?
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6th Grade PSI
The Roles of Water
Forces of the Water Cycle Homework
Name: ______________________
6th Grade PSI
18. How does gravity impact the water cycle?
19. Where is heat transferred during the water cycle?
20. Why is the impact of solar energy different across the globe?
21. In what regions of the Earth would you find the warmest water? In what region
would you find the coolest water?
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6th Grade PSI
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Global Pattern of Ocean Currents Classwork
Name: ______________________
6th Grade PSI
22. What is an ocean current?
23. Which stores more energy: landmasses or oceans? Why?
24. How long does it take for a current to flow throughout the entire network of
currents?
25. What is the Global Conveyor Belt?
26. Explain what causes the ocean currents to rotate differently in the northern and
southern hemispheres.
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6th Grade PSI
The Roles of Water
Global Pattern of Ocean Currents Homework
Name: ______________________
6th Grade PSI
27. Define the term gyre.
28. What impact does wind have on the ocean currents?
29. What powers the Global Conveyor Belt?
30. How do water temperature and the position of landmasses influence ocean
currents?
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6th Grade PSI
The Roles of Water
Erosion and Weathering Classwork #1
Name: ______________________
6th Grade PSI
EASTER ISLAND STONE HEADS ARE 'DYING'
Gigantic statues will vanish without preservation effort
Written by Jen Ross
December 6, 2007
Sloping slightly sideways on the grassy hills beneath the Ranu Raraku volcano, a giant stone
head known as a moai shows the wear and tear of time on this triangular 64-square-mile island.
On the right side of the oblong rectangular face with male features, the rock is lighter in color
and its long, carefully sculpted ear and nostril are clearly visible. But on the statue's left side, the
sun and wind have eroded the nose, lip and ear.
"The moai are dying by natural causes," said archaeologist Sergio Rapu, a lifelong researcher
of this isolated South Pacific island of hills and extinct volcanoes also known as Rapa Nui. "The
prehistoric Rapa Nui people noted it would take 300 to 400 years for the statues to become
completely eroded."
Such predictions loom bleak for the island's nearly 1,000 signature moai statues, as the
constant battering of erosion and rain is slowly eating away at the island's porous volcanic
stone.
Easter Island is among the world's most isolated inhabited islands with about 4,000 inhabitants.
It lies 2,237 miles west of Chile, which annexed the island in 1888. It is a UNESCO World
Heritage Site.
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Rapu said erosion can be stopped by using chemical resins that seal the stone, as well as
stabilizing the ahu, or altar platforms that support some of the moai, many of which are slowly
falling into the ocean. But that would be costly, he said.
Archaeologists had hoped this summer's New Seven Wonders of the World contest - organized
by Swiss film producer and philanthropist Bernard Weber - would spark the release of funds to
restore the moai. The statues were carved between 1200 and 1550 to honor the gods. After
placing in the top 10 favorite sites during preliminary results, the island failed to make the final
seven, chosen by 100 million people in a popular vote by Internet, phone and mail. When the
moais finished eighth, Weber sent Chile a letter saying the statues were "morally" one of the
New Seven Wonders, according to the local press.
In the meantime, Jose Antonio Viera, minister of the presidency, said it is urgent for the Chilean
government and the international community to come to the rescue. Despite reconstruction
efforts by U.S. archaeologists in the 1970s, Japan has been the only country in the past decade
to offer significant financial assistance - $671,000 - to restore the sculptures.
"Obviously, Easter Island is Chile's No. 1 cultural heritage site," Viera said. "It has been
overseen by the state. ... But we could do a thousand times better."
Chile's President Michelle Bachelet has pledged to help preserve Easter Island by passing
legislation to create a national heritage institute on Easter. In August, the Chilean Congress
passed a bill, granting islanders greater authority over governance, fishing, tourism and bilingual
education in Rapa Nui and Spanish.
"When Rapa Nui became a candidate for the wonders of the world, it was an alarm bell for
authorities to wake up and look at what's going on," Rapu said.
Local activists also say the moai face threats from tourism, which has more than doubled in the
past three years from 22,000 visitors in 2003 to more than 50,000 in 2007, according to the
ministry of tourism. Although much of the island is protected by the Rapa Nui National Park,
there are only 12 park rangers, Rapu said.
"It's sad to say that after more than 40 years, the national park of Easter Island doesn't have a
budget of more than $300,000 a year," he said. "I've estimated that it needs at least $3 million a
year. Otherwise, we're just faking" (protecting the reserve).
Many locals - about 60 percent are native Polynesians - say tourism is straining the island's
meager infrastructure. Since the 1990s, they say, tourism has brought increasing problems with
garbage collection, sewage disposal, and destruction of archaeological sites.
Edgard Hereveri, president of the Rapa Nui Chamber of Tourism, said losing the Seven
Wonders of the World contest may have been a godsend for the fragile island.
"If we are already unable to control the tourist traffic we currently have, how would we control it
after all the publicity around the contest?" asked Hereveri, recalling the influx of visitors after the
release of the 1994 Hollywood movie, "Rapa Nui."
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Julio Hotus, who heads the island's Department of Culture and Tourism, said he witnessed the
father of Chile's minister of national property hit a moai with a stone to show his wife how they
were carved. He was fined $6,000.
"When tourism began on the island, locals saw tourists as cattle, and believed the more they
brought to the island, the more money they'd make," said Hoto. "But that has changed."
Now, local guides such as Cristian Reyes set ground rules with tourists before beginning any
tour. "You have to respect the archaeological sites. That means that you're not allowed to touch
the moai, and you're not allowed to step on the altars," he recently told two dozen tourists.
But throughout the tour, Reyes was forced to gently reprimand a handful of visitors who
clambered onto not-so-clearly marked altars to take pictures.
Rapu said efforts to preserve the island and its culture must be accompanied by educational
programs. He pointed out that 10,000 archaeological sites of varying sizes are in the hands of
private owners, who need to be engaged in the preservation. Rapu suggested paying them a
protector's fee per archaeological site.
"That way, each one of the landowners will become permanent park rangers," he said. The
"advantage is that they don't have social security, they don't go on strike, and they work Monday
to Monday because they are permanently on the site."
Questions:
1. What do scientists believe is causing these stone statues to “die”?
2. What are some measures that archaeologists can take to help preserve these
statues? What are the drawbacks of carrying out these measures?
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3. In what country can you find Easter Island?
4. Imagine that you are to take part in a debate with the national government over
the statues on Easter Island.
In your eyes, is it important to preserve these statues? Clearly explain your
argument.
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6th Grade PSI
The Roles of Water
Erosion and Weathering Classwork #2
Name: ______________________
6th Grade PSI
31. What are the results of weathering and erosion?
32. What is the difference between weathering and erosion?
33. What is the common element/force between weathering and erosion?
34. Are weathering and erosion interdependent or independent forces? In other
words, do both have to always happen at the same time and rely on each other
(interdependent), or can they happen on their own (independent)? Explain.
35. Define the term sediment.
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6th Grade PSI
The Roles of Water
Erosion and Weathering Homework
Name: ______________________
6th Grade PSI
36. Define the term deposition.
37. What force is in play when water freezes in the crack of a rock?
38. How are sink holes and caverns examples of weathering and erosion?
39. What role do glaciers play in weathering and erosion?
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Answer Key
The Water Cycle Classwork
1) Water is never destroyed because the Earth is considered a closed atmosphere.
Water is continuously recycled through the water cycle.
2) True. The water on Earth is millions of years old and simply gets recycled.
3) The sun powers the water cycle. Two ways it causes changes to water are that it
melts ice and it causes liquid water to evaporate.
The Water Cycle Homework
4) False. The water cycle is composed of many sub cycles and constantly changes.
5) Evaporation itself is difficult to see but through the effects of condensation we can
prove it is happening. Evaporation can be seen through steam, such as when you
shower. Its effects can also be seen in the condensation of dew on a lawn or when
you hold a cup over a boiling pot of water. You can also tell that evaporation has
occurred when you see puddles drying up the day after heavy rainfall.
6) Water tanks, ponds, reservoirs, etc.
7) If the water cycle stopped life as we know it would stop. Things would dry out and
all the water might be unusable.
8) Even on cloudy the solar energy from the sun powers the water cycle because it
still is providing heat to the Earth.
States of Matter in the Water Cycle Classwork #1
9) Condensation is the opposite of evaporation. In evaporation, the liquid water
becomes a gas. In condensation, the gas becomes a liquid again.
10) Answers will vary. Example: Liquid water is evaporated into a gas, the gas
condenses into a cloud, precipitation falls from the cloud in a frozen solid state.
11) Condensation is the conversion of a gas into a liquid.
States of Matter in the Water Cycle Classwork #2
1) The purpose of this project is to provide more clean drinking water to the people of
Orange County. This project is necessary because the area needed a renewable
source of fresh water to help it deal with its growing population. It also helps reduce
the amount of wastewater sent out to the Pacific Ocean.
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6th Grade PSI
The Roles of Water
2)
Microfiltration
This process gets rid of bacteria, protozoa, and suspended
solids in the liquid by pushing it through a series of tiny,
hollow tubes.
Reverse
Osmosis
The water passes through special plastics sheets where
harmful materials as small as a molecule get separated out.
Ultraviolet
Disinfection
Any remaining viruses are killed with ultraviolet light bulbs.
3) An aquifer is an underground freshwater supply. These underground supplies are
important to the communities of Orange County because they help provide water to
their large populations.
4) Possible answers include: more clean drinking water, less pollution being pumped
out into the Pacific Ocean, less water that needs to be shipped in from Northern
California, and the production of water that exceeds all standards.
5) Answers will vary.
States of Matter in the Water Cycle Homework
12) Answers will vary.
13) Water can be temporarily stuck in a glacier, lake or ocean. However, eventually the
water will return to the water cycle, although it may take thousands of years or
more.
14) Evaporation and transpiration are examples of a liquid turning into a gas.
Forces of the Water Cycle Classwork #1
15) The forces behind the water cycle are the sun, gravity, atmosphere and landforms.
16) The oceans in the polar regions are cooler because they receive less solar energy
from the sun due to the curvature of the earth.
17) Other impacts of the Coriolis Effect include the way airplanes or missiles move.
Forces of the Water Cycle Classwork #2
1) Global warming is the increase in average temperature of the Earth’s air and
oceans. This is causing the water of the Chesapeake Bay region to warm up,
which could have an effect on the wildlife in the area.
2) Some animals in the region are only found in cold water, which means that they will
be unable to live in the region anymore. Other animals could be affected by more
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The Roles of Water
frequent droughts that could come as a result of this warming. Some plants would
be unable to survive in a warmer climate as well. This would have a ripple effect on
animals that rely on these plants for food and protection. Finally, rising
temperatures could cause animals to misread environmental cues that help them
determine their reproduction and feeding schedules.
3) Answers will vary, but could mention an increase in air temperatures.
4) Answers will vary, but some examples could include: limiting the amount of driving,
buying fuel-efficient or alternative fuel cars, using less electricity, etc.
Forces of the Water Cycle Homework
18) As water is evaporated by the sun and lifted into the atmosphere, gravity pulls the
water back to Earth in the form of precipitation. Gravity also causes the runoff to
flow through rivers and streams back to the ocean. Along its way gravity pulls
against the water eroding the earth, cutting canyons and transporting sediments.
19) As water is constantly traveling through the water cycle it is releasing its absorbed
heat. The heat from the Sun that causes water to evaporate is put into the air when
the water condenses into clouds and precipitates. The continuous evaporation and
condensation cycle is a main way heat is transferred from the Earth's surface to the
atmosphere and in moving heat around the Earth.
20) While solar energy influences all surface process, its impact is not consistent
because the Earth is a sphere. The amount of sunlight and its influence depends
on the angle of the earth in relation to the sun.
21) The warmest water would be found closest to the equator and the coolest water
would be found closest to the poles.
Global Pattern of Ocean Currents Classwork
22) An ocean current is the movement of ocean water that flows in one of the Earth's
oceans.
23) When compared to the land masses on Earth, the oceans store much more heat.
Since the majority of the thermal energy on Earth is stored in the oceans, they are
important in the regulation of Earth’s climate.
24) It takes approximately 1000 years for a current to complete the cycle.
25) The Global Conveyor Belt is a deep ocean current that is fueled by differences in
temperature and salinity.
26) The rotation of the Earth causes the current in the northern hemisphere to rotate
clockwise and currents in the southern hemisphere to rotate counter clockwise.
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Global Pattern of Ocean Currents Homework
27) A gyre occurs when the warm equatorial surface waters move towards the poles
where they cool and return back towards the equator along the sea floor.
28) Wind blowing over the warm ocean water helps move the surface water and push
the current along.
29) Differences in temperature and salinity power the Global Conveyor Belt.
30) Water temperature influences the currents because they move from warm to cold.
Landmasses influence currents by changing or redirecting their course.
Erosion and Weathering Classwork #1
1) These statues are “dying” because they are being eroded and are not being
properly protected from tourists and from nature.
2) Erosion could be stopped by using chemical resins that seal the stone and also can
stabilize the altar platforms that the statues sit on so that they do not fall into the
ocean. The drawback is that these measures are expensive.
3) Easter Island is located in Chile.
4) Answers will vary.
Erosion and Weathering Classwork #2
31) Both weathering and erosion change Earth’s landscape. Weathering causes rock,
soil and minerals to break into small pieces. Erosion is when these small pieces
are carried and deposited somewhere new. This changes both the original
environment and the one that is receiving the new material.
32) Weathering is the breaking down of rock, soil and minerals into small sediments.
Erosion is when these small pieces are carried and deposited somewhere new.
33) There are two common elements of weathering and erosion: wind and water.
34) Erosion relies on weathering in order to occur. For the most part, erosion will only
happen after large objects have been broken into much smaller pieces. This makes
it easier for wind and water to move these pieces.
35) Sediments are tiny pieces of rocks.
Erosion and Weathering Homework
36) Deposition is when soil and rocks are deposited or left somewhere different than
where they started.
37) Weathering is occurring when water freezes in a rock crack. The expansion of the
water breaks the rock into smaller pieces and sediments.
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6th Grade PSI
The Roles of Water
38) Sink holes and caverns are proof of underground weathering and erosion. They
show that rocks and soil were broken down and then carried away.
39) Glaciers can both cause weathering and erosion. Glaciers can move sediment
from one area to another. They can also change the landscape through their own
formation and breaking apart. They can create valleys and cause changes in the
surrounding rock and mountain formations.
www.njctl.org
6th Grade PSI
The Roles of Water