Teacher Resources

Student Handouts	Items for Group Display	Material Items	Facility/Equipment Requirements
Investigation 1: Ch-ch-ch-changes
Science notebooks  Arctic sea ice data Scatterplot example Sea ice flip book	video “Alaskan Native Thoughts on Climate Change” video "George Divoky: The BirdWatcher Who Saw the Future” Shrinking Ice Headlines PowerPoint Sea ice animation	Graph paper 1B: Melting Sea Ice and Sea Level For each pair of students: Water 1 clear plastic 6-8 oz. cup Permanent felt-tip marker or tape Ice cube 1C: Temperature and Sea Level Conical flask Two-hole cork for flask Thin glass tube Long thermometer Portable clamp-on reflector lamp 150-watt floodlight Dye or food coloring Graph paper	Projector and/or computers to view online videos and PowerPoint Internet access Chart paper or board
Investigation 2: Impacts of Change in Glacier Ice
Science notebooks Alaska glacier photos Glacier photo comparison worksheet "Small fry may be big problem" article Transparency/Turbidity Lab instructions Glacier Game Board #1 or Glacier Game Board #2	Stream table	2B: Melting Ice Each pair of students will need: Plastic cup or other container that will hold water Clay, wood, or other material to represent land in the container Ice cube Permanent marker or tape Water 2C: Stream Table Materials needed: Cookie sheet or foil pan Sand Potting soil Gravel (optional) Water source (a bucket with water in it or a watering can) Funnel Pieces of hose or other soft tubing Books or block (to elevate the table) 2D: Transparency/Turbidity    Sticky note pads Per student group: Large containers with water (1,000 ml beakers) Powdered milk Ruler (with centimeters) String White plastic container lid Nail or sharp object to make a hole in the lid Permanent black marker Pencil and data sheet Duct tape Nuts or washers or something similar for a weight Measuring cups Calculator 2E: Glacier Game Printed and assembled game board per 2-3 students 1 dice for each student group Game markers	Chalkboard, whiteboard, or overhead projector Access to sink or other water source Computer with projector Student computers, preferably one per student or pair of students
Investigation 3: Bering Sea Expedition
Science notebooks WebQuest Presentation Rubric	video “Climate-driven Change in the Northern Bering Sea"	Posterboard and art materials for presentations if PowerPoint is not used	Projector and/or computers to view online videos and PowerPoint Internet access Computer and Internet access for students
Investigation 4: Changes in Our Local Environment
Science notebooks Photo Comparison Worksheet Photos of the local area	One or more of the following videos: Saving a Community: Shishmaref, Alaska Orville Huntington, “It’s a Changing Thing” Richard Glenn, At Home in Two Worlds	Video cameras or digital cameras for interview and photos Tape recorders for interview Pens or pencils Paper Clipboard Blank paper Any old outdoor photographs of your community that you can find	Computers and software to download photos, create newspaper. Printer or quick photo processing service
Investigation 5: Explaining Impacts of a Warming Climate
Science notebooks Digital Story rubric	Climate change videos For Community Presentation: Tools, instruments, photos, and “artifacts” from Investigation 4 and previous investigations as appropriate.	Poster board and art supplies if needed for presentations. Invitation materials and supplies for potluck if applicable. Computer and appropriate software for each student group Digital cameras, video cameras if available Drawing materials	Computer access for online research, word processing, and development of story. Software such as iMovie, PowerPoint, Photo Story 3, etc. If available and desired: video cameras and editing software Digital projector

Our Changing World addresses the following GLEs for grades 6, 7 and 8:

Grade Level Expectations for Grade 6	Investigation
	1	2	3	4	5
The student demonstrates an understanding  of the processes of science by: SA1.1 asking questions, predicting, observing, describing, measuring, classifying, making generalizations, inferring and communicating.	x	x	x	x	x
The student develops an understanding of the processes of science by: SA1.2 observing and describing their world to answer simple questions.	x	x		x
The student demonstrates an understanding that interactions with the environment provide an opportunity for understanding scientific concepts by: SA3.1 observing local conditions that determine which plants and/or animals survive. (L)		x		x	x
The student demonstrates understanding of the structure and properties of matter by SB1.1 using models to represent matter as it changes from one state to another		x
The student demonstrates an understanding of the interactions between matter and energy and the effects of these interactions on systems by SB3.1 recognizing that most substances can exist as a solid, liquid, or gas depending on temperature		x
The student demonstrates an understanding of how science explains changes in life forms over time, including genetics, heredity, the process of natural selection, and biological evolution by SC1.2 recognizing that species survive by adapting to changes in their environment		x
The student demonstrates an understanding that all organisms are linked to each other and their physical environments through the transfer and transformation of matter and energy by SC3.2 organizing a food web using familiar plants and animals		x	x
The student demonstrates an understanding of the forces that shape Earth by SD2.3 describing how the surface can change rapidly as a result of geological activities (i.e., earthquakes, tsunamis, volcanoes, floods, landslides, avalanches).		x
The student demonstrates an understanding of how to integrate scientific knowledge and technology to address problems by SE1.1 recognizing that technology cannot always provide successful solutions for problems or fulfill every human need.
The student demonstrates an understanding that solving problems involves different ways of thinking by [6] SE2.1 identifying and designing a solution to a problem.		x
The student demonstrates an understanding that solving problems involves different ways of thinking by: [6] SE2.2 comparing the student’s work to the work of peers in order to identify multiple paths that can be used to investigate a question or problem. (L)	x	x	x
The student demonstrates an understanding of how scientific discoveries and technological innovations affect our lives and society by SE3.1 describing the various effects of an innovation on a global level.			x

 

Grade Level Expectations for Grade 7	Investigation
	1	2	3	4	5
The student develops an understanding of the processes of science by: [7] SA1.1 asking questions, predicting, observing, describing, measuring, classifying, making generalizations, inferring, and communicating.*	x	x	x	x	x
The student demonstrates an understanding of the processes of science by: [7] SA1.2 observing, measuring, and collecting data from explorations and using this information to classify, predict, and communicate. add new	x	x		x
The student demonstrates an understanding of the attitudes and approaches to scientific inquiry by [7] SA2.1 identifying and evaluating the sources used to support scienitifc statements aa new
The student demonstrates an understanding that interactions with the envrionment provide an opportunity for understanding scientific concepts by [7] SA3.1 designing and conducting a simple investigation about the local environment. (L)		x		x	x
The student demonstrates understanding of the structure and properties of matter by [7] SB1.1 using physical properties (i.e., density, boiling point, freezing point, conductivity) to differentiate among and/or separate materials (i.e., elements, compounds, and mixtures)		x
The student demonstrates an understanding of motions, forces, their characteristics, relationships, and effects by [7] SB4.3 describing the characteristics of a wave (i.e., amplitude, wavelength, and frequency)
The student demonstrates an understanding of the forces that shape Earth by SD2.2 describing how the movement of the tectonic plates results in both slow changes (e.g., formation of mountains, ocean floors, and basins) and short-term events (e.g., volcanic eruptions, seismic waves, and earthquakes) on the surface.
The student demonstrates an understanding that solving problems involves different ways of thinking, perspectives, and curiosity by: [7] SE2.1 identifying the function of a variety of tools (e.g., spear, hammer, hand lens, kayak, computer)
The student demonstrates an understanding that solving problems involves different ways of thinking, perspectives, and curiosity by:  [7] SE2.2 identifying multiple explanations (e.g., oral traditions, folklore, scientific theory) of everyday events (e.g., weather, seasonal changes). (L)*	x	x	x
The student demonstrates an understanding of how scientific discoveries and technological innovations affect our lives and society by SE3.1 recognizing the effects of a past scientific discovery, invention, or scientific breakthrough (e.g., DDT, internal combustion engine).
The student demonstrates an understanding of the dynamic relationships among scientific, cultural, social, and personal perspectives by SF1.1-SF3.1 investigating the basis of local knowledge (e.g., describing and predicting weather) and sharing that information (L)				x
The student demonstrates an understanding that scientific knowledge is ongoing and subject to change by SG3.1 revising a personal idea when presented withexperimental/observational data inconsistent with that personal idea (e.g., the rates of falling bodies of different masses)* (L)	x

 

Grade Level Expectations for Grade 8	Investigation
	1	2	3	4	5
The student demonstrates an understanding  of the processes of science by: [8] SA1.1 asking questions, predicting, observing, describing, measuring, classifying, making generalizations, inferring, and communicating.	x	x	x	x	x
The student demonstrates an understanding of the processes of science by: [8] SA1.2 using quantitative and qualitative observations to create their own inferences and predictions.	x	x		x
The student demonstrates an understanding of the attitudes and approaches to scientific inquiry by SA2.1 recognizing and analyzing differing scientific explanations and models.	x	x
The student demonstrates an understanding that all organisms are linked to each other and their physical environments through the transfer and transformation of matter and energy by SC3.1 stating that energy flows and that matter cycles but is conserved within an ecosystem			x
The student demonstrates an understanding of the forces that shape Earth by SD2.1 interpreting topographical maps to identify features (i.e., rivers, lakes, mountains, valleys, islands, and tundra).	x
The student demonstrates an understanding that solving problems involves different ways of thinking, perspectives, and curiosity by: [8] SE2.1 investigating a problem or project over a specified period of time and identifying the tools and processes used in that project. (L)*
The student demonstrates an understanding that solving problems involves different ways of thinking, perspectives, and curiosity by: [8] SE2.2 comparing multiple explanations (e.g., oral traditions, folklore, scientific theory) of everyday events (e.g., weather, seasonal changes). (L)	x	x	x
The student demonstrates an understanding of how scientific discoveries and technological innovations affect our lives and society by SE3.1 predicting the possible effects of a recent scientific discovery, invention, or scientific breakthrough (L).  ADD	x	x	x
The student demonstrates an understanding of the dynamic relationships among scientific, cultural, social, and personal perspectives by SF1.1-SF3.1 describing how local knowledge, culture, and the technologies of various activities (e.g., hunting, fishing, subsistence) influence the development of scientific knowledge (L).				x
The student demonstrates an understanding that scientific knowledge is ongoing and subject to change by SG3.1 revising a personal idea when presented withexperimental/observational data inconsistent with that personal idea (e.g., the rates of falling bodies of different masses)* (L)	x

(L) Some GLEs have been identified as Local. They are for local assessments and will not be on a state assessment.

* PSGLEs repeated with no changes across grade levels are marked with asterisks.

 

Printed Materials

Pfeffer, T. The opening of a new landscape: Columbia Glacier at mid-retreat. American Geophysical Union, 2007.

Post, A. and E. LaChapelle. Glacier Ice. University of Washington Press, 1971.

Investigation 1: Ch-ch-ch-changes
Video “Alaskan Native Thoughts on Climate Change”
Video "George Divoky: The BirdWatcher Who Saw the Future” about a poplulation of black guillemots near Barrow, Alaska

Investigation 2: Impacts of Change in Glacier Ice
Explanation and photos of glacier topics can be found at Teachers Domain
Glaciers Online. Includes many photos and videos of glaciers from around the world.
USGS Benchmark Glaciers. Information, graphs and links to reports about Gulkana and Wolverine glaciers in Alaska.
NOVA Science Now: Video of a moving Jakobshavn glacier in Greenland
How Glaciers Move. Alaska Science Forum, Article #145
Journey to Alaska’s Glaciers: WebQuest to Explore How Glaciers Shape the Land
National Snow and Ice Data Center Repeat Photography of Glaciers
NOAA's Tides and Currents site and click on the Gulf of Alaska.
The Center for Remote Sensing of Ice Sheets has an interactive world map of sea level rise.
Peninsula Online news article, "Small fry may be big problem"

Investigation 3: Bering Sea Expedition
Come on board the Healy! Video of researchers on the Healy.
“Climate-driven Change in the Northern Bering Sea." This video shows scientists aboard the icebreaker Healy talking about melting ice and how climate change is altering the food chains in the Bering Sea. 

WebQuest Resources:
Part 1: Bering Sea Research
Physical/geographic description of the Bering Sea, with maps showing bathymetry, currents, habitats, islands, and sea.
Description of Bering Sea ecostystem and wildlife, and threats to wildlife
NASA site with satellite imagery showing and describing physical attributes, seasons and changes in the Bering Sea

Part 2: Organism Research
Brief description and photos of arctic species at risk due to climate change
Descriptions and photos of arctic marine life from diatoms to whales, with links to additional information
Alaska Ocean Observing System: Information and learning activities about marine mammals and birds
Interactive Bering Sea/arctic ecosystem with info on key species:
Canadian Museum of Nature: Life Under the Ice, Amphipods

Ice Algae
Wikipedia: Ice Algae
NOAA article about algae and other organisms that live within sea ice
Canadian Museum of Nature: Life Under the Ice, Arctic Sea Ice Core
Canadian Museum of Nature: Life Under the Ice, Microscopic phytoplankton

Copepods
The Biology of Copepods
Wikipedia: Copepods
Copepods

Krill
National Geographic Krill profile with photo
Wikipedia: Krill

Clam (Macoma spp)
Macoma clam

Jellyfish
The Jellies Zone
Jellyfish: Oregon Aquarium
Wikipedia: Jellyfish

Sea Urchins
Wikipedia: Sea Urchins
Canadian Museum of Nature: Life Under the Ice, Sea urchins
Sea Urchin Natural History

Bering Sea Seabirds
Least Auklet
Alaska Seabirds Information Series: Least Auklet
Whatbird.com – Least Auklet
Birds of North America Online: Least Auklet

Black-legged Kittiwake
Alaska Seabirds Information Series: Black-legged Kittiwake
Birds of North America Online: Black-legged Kittiwake
Cornell Lab of Ornithology All About Birds: Black-legged Kittiwake

Spectacled Eider
Alaska Dept. of Fish and Game Notebook Series: Eider
BBC interview with Jim Lovvorn: Spectacled Eider
Field notes: Spotlight On… Spectacled Eiders

Arctic cod
Canadian Museum of Nature: Life Under the Ice, Arctic Cod
Wikipedia: Arctic cod
Arctic cod information, description, distribution and ecology

Bering Sea Marine Mammals
Walrus
Canadian Museum of Nature: Life Under the Ice, Walrus
U.S. GEOLOGICAL SURVEY
Fact Sheet: Pacific Walrus Response to Arctic Sea Ice Losses
Alaska Dept. of Fish and Game Notebook Series: Walrus

Ringed Seal
Canadian Museum of Nature: Life Under the Ice: Ringed Seal
Alaska Dept. of Fish and Game Notebook Series: Ringed Seal
National Marine Mammal Laboratory: Ringed Seals

Bowhead Whale
Alaska Dept. of Fish and Game Notebook Series: Bowhead Whale
Bowhead Whales in Alaska
National Marine Mammal Laboratory: Bowhead Whales

Right Whale
National Marine Mammal Laboratory: Right Whales
North Pacific Right Whale
American Cetacean Society: Right Whale

Polar Bear
Alaska Dept. of Fish and Game Notebook Series: Polar Bear
Canadian Museum of Nature: Life Under the Ice: Life Under the Ice: Polar Bears
National Geographic: Polar Bear

Investigation 4: Changes in Our Local Environment

A Half-Century of Change in Arctic Alaskan Shrubs: A Photgraphic-Based Assessment

Video Saving a Community: Shishmaref, Alaska
Video Orville Huntington, “It’s a Changing Thing”
Video Richard Glenn, At Home in Two Worlds

Interview questions:
Observing Locally, Connecting Globally Sample Interview Questions for Grades K-12
Student Led Weather Interview for Grades 7-12
Arctic Borderlands Ecological Knowledge Co-op Comprehensive Environmental Monitoring Interview
Interview Questions from Climate Change North

Alaska’s Digital Archives may also have historic photos of your community and surrounding areas.

Investigation 5: Explaining Impacts of a Warming Climate

Ideas for introducing students to digital storytelling:

Center for Digital Storytelling 

How to Create a Digital Story 

Digitales 

Educational Uses of Digital Storytelling 

Creating a Storyboard

Storyboard Organizer to help students plan their digital story.

This movie is an example of using still photos, text, and music to create the story: Global Warming - Climate Change

CFL Lightbulbs in Plain English: An easy, but effective way to create a story, using narration, cutouts, a white board, and hands.

The following were created by students: 
AP Biology Legacy Project

The Rock Cycle Movie What is Global Warming? Text, images and student narration.

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Ocean and stream environments are dynamic. For people living along the coast of Alaska or along its rivers, daily changes are often obvious and they have adapted their lives to the rhythms of change. On the coast and for some distance up large rivers, the tide comes in and goes out twice a day. In places where the ocean is funneled up a narrow channel like Cook Inlet, the tidal range can be extreme when the gravitational pull of the sun and moon are combined. Storms come and go, often with high winds that whip the surface of rivers, lakes, and the ocean into turbulence. Rainy periods cause streams and rivers to rise and flood; dry periods cause them to fall and recede. Break-up and freeze-up are part of an annual cycle throughout much of Alaska, as is the freezing and thawing of sea ice in the Arctic Ocean and Bering Sea and bays in Southcentral Alaska.

The “big picture” of physical changes in marine and aquatic environments over long periods of time has involved cyclic ice ages that affected the entire planet. Long-term reductions in the temperature of the earth’s surface and atmosphere resulted in an expansion of continental ice sheets, polar ice sheets, and alpine glaciers. During ice age peaks, extensive ice sheets were present on what is now Alaska and other areas of the North American and Eurasian continents. Much of the planet’s water was locked in ice, greatly reducing the amount of water in the ocean, thus lowering sea levels, exposing continental shelves, and forming a land bridge between North America and Asia. As the ice thawed, sea levels rose, the shoreline of the continents moved inland, large expanses of land emerged from beneath the receding glaciers, and large rivers were formed that cut their way to the sea. During the last great ice age, much of Alaska and Russia was not glaciated, but was rather dry grassland. This was known as the Mammoth Steppe. (http://www.gi.alaska.edu/ScienceForum/ASF18/1809.html). This stresses one of the important ideas about glaciers, which is that they require more than just cold temperatures to form. They require precipitation in the form of snow.

We are now living in what may be an interglacial period, or between ice ages. The climate is warm enough that the extent of both sea ice and some alpine glaciers are shrinking. Considerable scientific evidence supports the conclusion that the trend of the overall climate of the planet is warming, and at an accelerating rate. This warming pattern can change the conditions for life in Alaska’s aquatic and marine environments, and affect the diversity and productivity of ecosystems that have existed and adapted to conditions only since the peak of the last ice age.

Physical changes and their effects on marine and aquatic ecosystems are the focus of the unit—with an emphasis on changes in the extent of the area covered by ice through the seasons and permanently, as well as changes in the nature of the freshwater that reaches the ocean as glaciers thaw.

According to the National Snow and Ice Data Center, "Arctic sea ice during the 2007 melt season plummeted to the lowest levels since satellite measurements began in 1979. The average sea ice extent for the month of September was 4.28 million square kilometers (1.65 million square miles), the lowest September on record, shattering the previous record for the month, set in 2005, by 23 percent Arctic sea ice extent during the 2008 melt season dropped to the second-lowest level since satellite measurements began in 1979, reaching the lowest point in its annual cycle of melt and growth on September 14, 2008."

The scientific evidence supports the conclusion that these effects are taking place on a global scale, although they are not happening uniformly in every place on the planet. While many glaciers are melting at lower elevation in response to warmer air temperatures and increased rainfall, some glaciers are “fed” at higher elevations, where precipitation falls as snow, and are growing in size. Parts of Alaska have recently experienced seasons that are, on average, colder than in years past, and ocean water temperatures are colder with nearshore ice lingering longer than on average. Overall, however, the planet’s climate appears to have a warming trend. This unit explores the potential effects of a warming climate, particularly one that warms rapidly with respect to the organisms adapted to a cooler regime and large-scale pattern of change.

Among the potential effects of a warming climate and melting sea and glacial ice:

• Less sea ice (smaller area and a later initiation of growth during winter) may mean more open water during the summer with a larger capacity to absorb and store heat, thus increasing the rate of the melting of the sea ice, independent of air temperatures.
• Less sea ice will affect the species of fish and wildlife that are adapted to the current balance and cycle of sea ice, land, and open water.

• Whales that require large concentrations of zooplankton may have more difficulty finding the smaller number of “patches” of zooplankton they prefer, or instead they may find zooplankton that thrive in warmer seas.
• For many species, the timing of food availability is critical and may be altered by climate change.
• Increased freshwater runoff to the ocean may increase flooding and raise sea level.
• The effect of melting glaciers may also have dramatic physical effects on the land, streams, and nearshore areas of the ocean where water runs off the land directly and at the mouths of streams and rivers.

Investigation 1: Ch-Ch-Ch-Changes
Climate patterns are dynamic. Mounting scientific evidence is documenting a current warming trend that is being magnified in intensity at the poles. This unit does not seek to engage students in the entirety of this complex topic. Instead, it focuses on one aspect of the dynamics of marine and aquatic environments for which there is currently considerable scientific data on large-scale change—changes in sea ice and glaciers. The activities support exploration of the scientific evidence of change, the processes of change, and possible consequences of a climate trend that may continue to increase the melting of sea ice and glaciers. For an overview of global ice changes in the “cryosphere,” as observed from space, see the seven-minute Cryosphere Movie.

Sea Ice
Sea ice is frozen sea water. (Icebergs are not sea ice because they are fragments of freshwater glaciers). For more information about the characteristics of sea ice and information on the record loss of arctic sea ice during the summers of 2007 and 2008, read the  news on the National Snow and Ice Data Center Web site.

Effects of a Warming Climate
A warming climate is expected to result in the increased rate of melting of sea ice and glaciers. Sea level is rising, according scientific evidence, although there is disagreement about how to accurately measure the change and the magnitude of the predicted rate of rise in the future. The melting of sea ice is not expected to contribute significantly to sea level rise for reasons the students will explore in Investigation 1 in this unit. The melting of glaciers and the thermal expansion of water are expected to be the primary processes that will determine the rate of rise. The melting of sea ice will have a significant effect on arctic and subarctic ecosystems, which will be explored in the Bering Sea WebQuest in Investigation 3.

Resources:
Alaska Ocean Observing System. Arctic sea ice animations: Real-time and longer time series real-time or near real-time data on the extent of seasonal ice.

National Snow and Ice Data Center. Daily image of arctic sea ice and time-series graph, and results of recent data analyses.

Global Climate Change NASA's Eyes on the Earth Key Indicators has graphs of historic data on sea level change, ice mass, and other indicators of climate change such as global average temperature, and ozone hole size.

NASA Web site with visualization of arctic sea ice extent, 1979-2007, graphic and graph.

Activity 1B: Melting Sea Ice and Sea Level
Explanation for the results of the experiment: Ice is less dense than water. An ice cube floating in a glass of water displaces the same volume of water that it contains. So, if sea ice were to melt, the sea level would stay the same.

The Arctic region encompasses the Arctic Ocean and the surrounding northern boundaries of several continents (North America, Europe, Asia) and the earth’s largest island, Greenland. Between these landmasses it connects with the other oceans of the world, and thereby has an impact on global weather and climate. Much of the water is covered with sea ice, which increases and decreases seasonally in both thickness and total surface area. While roughly half of the arctic sea ice freezes and melts during this process, the remaining half remains frozen and grows in thickness over many years.

There are two kinds of ice in the polar regions—sea ice and glacier ice in the form of mountain glaciers and ice sheets. Sea ice forms on the top of ocean water and is usually between 1 and 2 meters thick after a cold winter, depending on where you are in the Arctic Ocean. Some of the sea ice melts each summer. Glaciers and ice sheets are formed on land from precipitation that falls and accumulates on the ground. Layers of snow build up, causing pressure on the snow crystals beneath, and the air is pushed out. Eventually the snow is compacted into layers of ice. This ice becomes a glacier that acts like a river, flowing downhill under the pressure of its own weight. Once the glaciers meet the ocean, they break off and become floating icebergs, or extend sometimes hundreds of miles into the ocean as ice shelves.

Be sure that students understand that temperature is not the only control on whether glaciers grow or shrink. Winter precipitation (snow) is also needed.

You may want to lead a discussion on the relationship between glacier accumulation and ablation (surface melting or iceberg calving). The size of a glacier is controlled by both of these things. Calving accounts for two-thirds of the mass loss from Greenland and an even higher proportion of the mass loss in Antarctica. Furthermore calving is at least partly controlled by changes in ocean temperature and circulation. So not only do glaciers contribute to sea level variations, they are also affected by changes occuring in the oceans. Calving also makes for a captivating subject: there are now many images and videos available of calving icebergs. Videos from work in Greenland can be found at ftp://ftp.gi.alaska.edu/pub/amundson/videos/.

The significance of the rate of melt of Alaska glaciers on a global scale, and the relative contributions of different melt and thermal expansion processes, is the subject of active research and sometimes-conflicting opinions. To see a recent synthesis of research about glaciers, ice sheets, and global sea level rise, see the summary of a lecture by Eric Rignot of the Jet Propulsion Lab in November 2008.

Earthwatch Radio list
Alaska’s Melting Glaciers
Rising Waters (from glaciers)

Sea Ice
National Snow and Ice Data Center Web site

Investigation 2: Impacts of Change in Glacier Ice
Investigation 2 focuses on the consequences of melting glaciers, and compares the potential sea level effects of glacial melt with melting sea ice. Glacier photos and the Glacier Game engage students in the investigation of a suite of effects on aquatic and marine ecosystems. The Stream Table and Transparency/Turbidity activities provide hands-on experience with physical changes that will result from glacial melt.

Glaciers
For background on glaciers and the rate and impacts of glacial melt, read the section on glaciers from the National Snow and Ice Data Center. NSIDC data supports the conclusion that the majority of glaciers being monitored worldwide are retreating and the rate of retreat is accelerating.

The following diagram can help you visualize the processes that affect the mass balance of a glacier. The left side illustrates a tidewater glacier; the right side illustrates a glacier with runoff into a lake or stream.

 

 

 

 

 

 

 

 

Additional Resources:
A nice explanation and photos of glacier topics can be found at Teachers Domain.

NOVA Science Now: Video of the moving Jakobshavn glacier in Greenland

How Glaciers Move. Alaska Science Forum, Article #145

Journey to Alaska’s Glaciers: WebQuest to Explore How Glaciers Shape the Land

Isostatic Rebound
Isostatic rebound is the rise of land masses that were depressed by the huge weight of ice sheets during the last glacial period, through a process known as isostatic depression. It affects northern Europe, especially Scotland and northern Denmark, Siberia, Canada, parts of Alaska, and the Great Lakes region of Canada and the United States. Uplift has taken place in two distinct stages. The initial uplift following deglaciation was rapid (called "elastic"), and took place as the ice was being unloaded. After this "elastic" phase, uplift proceeded by "slow viscous flow," when the rate decreased exponentially. Today, typical uplift rates are of the order of 10 mm per year or less in most places, but are in the range of 10-32 mm per year at some locations in Southeast Alaska. This rebound is important in the context of sea level rise; the rate of rebound may equal or exceed the rate of sea level rise.

Glacier glossary

Activity 2C: Stream Table
What is a stream table? A stream table, most often used in earth science/geology classrooms, is a box-like table, usually containing sand, that is used to show the effects of a stream on land surfaces and features. Different types of streams can be manually produced (braided or meandering) by running fingers through the sand. Students are able to see the concepts of deposition and erosion on the "banks" of the streams formed on the table. Stream tables are available commercially or you can make your own.

How to Make a Stream Table

Materials needed:

• Cookie sheet or foil pan
• Sand
• Potting soil
• Gravel (optional)
• Water source (a bucket with water in it or a watering can)
• Funnel
• Pieces of hose or other soft tubing
• Books or block (to elevate the table)   

Cover the cookie sheet with a layer of sand, gravel, or potting soil. Use your finger to roughly etch out a stream. Prop up one end of the cookie sheet to about 3 to 5 cm.

Activity 2D: Transparency/Turbidity
The measure of how much light passes through water is also referred to as turbidity. The particles in water that scatter light may be microscopic plankton, stirred up sediment or organic materials, eroded soil, clay, silt, sand, industrial waste, or sewage. Bottom sediment may be stirred up by such actions as waves or currents, bottom-feeding fish, people swimming or wading, or storm runoff. Clear water may appear cleaner than turbid water, but it is not necessarily healthier. Water may be clear because it has too little dissolved oxygen, too much acidity, or too many contaminants to support aquatic life. Water that is turbid from plankton has both the food and oxygen to support fish and plant life. However, high turbidity may be a symptom of other water quality problems.
Effects of Turbidity

• Turbidity diffuses sunlight and slows photosynthesis. Plants begin to die, reducing the amount of dissolved oxygen and increasing the acidity (decaying organic material produces carbonic acid) which lowers the pH level). Both of these effects harm aquatic animals.
• Turbidity raises water temperature because the suspended particles absorb the sun's heat. Warmer water holds less oxygen, thus increasing the effects of reduced photosynthesis. In addition, some aquatic animals may not adjust well to the warmer water, particularly during the egg and larval stages.
• Highly turbid water can clog the gills of fish, stunt their growth, and decrease their resistance to diseases.
• The organic materials that may cause turbidity can also serve as breeding grounds for pathogenic bacteria. When drinking water reservoirs are turbid, the water treatment plant usually filters the water before disinfecting it.
• Industrial processes and food processing require clear water. Turbid water can clog machines and interfere with making food and beverages.

Causes of Excessive Turbidity

• Algae blooms caused by excess nitrogen (from agricultural runoff, septic tanks, or sewage outflows).
• Weather and seasons can contribute to turbidity. Water that is clear in the spring may grow turbid by August because of plant growth enhanced by warmer days and longer sunlight hours. Similarly, heavy rains or spring snow melts can stir up soil and sediments, increasing turbidity.
• Contamination from sewage, industrial waste, or urban runoff.

Investigation 3: Bering Sea Expedition

Climate Change and the Bering Sea. Information and videos of scientists talking about their research and changes in the Bering Sea.
Understanding Ecosystem Processes in the Bering Sea. For current research information and news about the Bering Sea.