Alaska Sea Grant

Grade 8 - Our Changing World

An 8-9 Week Unit for Middle School Level

Essential Questions:

  • How do changes in physical environment affect our ecosystems?
  • What impacts will a warming climate have on Alaska Seas and Watersheds?

Enduring Understandings:

  • Climate patterns cause physical changes in the environment.
  • Physical changes in the environment can change the conditions for life.
  • Science and technology can be used to detect and solve problems.

This unit is designed for 8th grade, but could be adapted for grades 6-8. Students learn how changes in physical environments affect our ecosystems by investigating how sea ice is changing over time and how melting glaciers affect stream flows, erosion, and habitats for fish and wildlife. They participate in a WebQuest to explore how a warming climate might affect life in the Bering Sea. Students then take a close look at changes in their local environment by interviewing long time residents and observing repeat photographs of the local landscape. Finally they create a digital story to share the potential effects of a warming climate with others.

Ocean Literacy Principles Addressed:

  • The Earth has one big ocean with many features.
  • The ocean supports a great diversity of life and ecosystems.
  • The ocean and humans are inextricably interconnected.
Investigation 1

Investigation 1: Ch-Ch-Ch-Changes
(6-8 days)

How is sea ice changing over time?
How do scientists determine and communicate the patterns of change in the extent of arctic sea ice?
What effect will a warming climate and melting sea ice have on sea level?

This 6-8 day investigation challenges students to think about how sea ice is changing and the effects of a warming climate on sea level in Alaska. Students begin by viewing a presentation showing a Native Alaskan talking about the importance of ice to his life and his culture. They then view a series of photos and headlines about shrinking sea ice. In Activity 1A: Arctic Sea Ice Data, students graph data on sea ice extent over time. In Activity 1B: Melting Sea Ice and Sea Level, students participate in a lab activity that simulates the melting of sea ice, and create a flip book of images of the change in sea ice extent over time. Activity 1C: Temperature and Sea Level Rise demonstrates the thermal expansion of seawater as one process that could contribute to sea level rise.

Investigation 2

Investigation 2: Impacts of Change in Glacier Ice
(9-11 days)

What changes occur in a landscape when a glacier melts and recedes?
Does melting glacial ice cause a change in sea level?
Will changes in sea ice or glacial ice cause the most change in sea level?
How do melting glaciers affect stream flows, erosion, and habitats for fish and wildlife?

In this 8-10 day investigation, students explore ways that changing climate can affect physical and biological conditions in rivers, the ocean, and other aquatic ecosystems. Activity 2A: Changing Landscape asks students to analyze “repeat photographs” (taken from the same vantage point at different times) of Alaska glaciers to observe the effects of retreating glaciers on the landscape. In Activity 2B: Melting Ice, students conduct a simulation to investigate the effect of melting glaciers on sea level. In Activity 2C, Stream Table, students simulate increasing stream flows that result from melting glaciers and observe the effects on the landscape and water quality. In Activity 2D: Transparency/Turbidity students construct a mini Secchi disk to investigate transparency and the effects of increased turbidity from the increased flows as glaciers melt on aquatic and marine ecosystems.
Finally, they play a board game in Activity 2E: Glacier Game to review the effects of retreating glaciers and increasing stream flows and erosion on river, coastal, and ocean ecosystems.

Investigation 3

Investigation 3: Bering Sea Expedition
(6-8 days)

How does a warming climate cause physical changes in the Bering Sea that will affect the conditions for life for a variety of species?
How can scientists use technology to detect alterations in food webs?
Why are these change important to people?

In this 6-8 day investigation, students use a WebQuest activity to research the effects of melting sea ice in the Bering Sea Ecosystem. The students create research proposals to earn a place on the scientific research vessel Healy, and present their findings and proposals to a “Research Board committee”.

Investigation 4

Investigation 4: Changes in Our Local Environment
(9-11 days)

What changes in our local environment have taken place over the last 50 years?
What are the major changes occurring in our local environment?
How do physical changes affect our local environment?

Students interview elders or other long-term residents of the community to document their knowledge of local changes to the landscape and climate. Based on the information and photos they acquired from the interview, students return to photo locations to observe and record changes. Finally, they develop ideas about potential impacts of a warming climate to the ecosystem that surrounds them.

Investigation 5

Investigation 5: Explaining Impacts of a Warming Climate
(3-12 days)

How can we help others learn about the potential effects of a warming climate on our community, in the Bering Sea and/or in the Arctic?
In this 3-12 day culminating activity, students will share their knowledge of the impacts of a warming climate with others by creating a digital story of the potential effects of a warming climate in their community, the Arctic, and/or the Bering Sea.

Derek Bynagle, Kenai Peninsula School District
Linda Casassa, Kuspuk School District
Brenda Papoi, Sitka School District
Carol Scott, Fairbanks Northstar Borough School District
Stephanie Hoag, Curriculum Consultant, Juneau
Marilyn Sigman, Science Content Specialist
Marla Brownlee, Alaska Sea Grant

Alaska Sea Grant University of Alaska Fairbanks Alaska Department of Education and Early Development NOAA