Observations of Climate Change

Global warming is a hot topic these days. But is it really relevant to you? Have you noticed changes in your surroundings that could be explained by global warming?

Next: How Does Global Warming Affect You?

Consider the following climate indicators. In your notebook, record any changes you have personally noticed in recent years.

• Precipitation: Consider the rainfall and/or snowfall in your surroundings over the past few years. Does it seem to you that you are experiencing more, less, or about the same amount now than you did a few years ago?
• Ponds/streams/waterways: Have you observed any changes in the depth of ponds, rivers, or streams between this year and past years?
• Insects: Have you noticed any change in the number of insects where you live? Have you seen any new species that you've never seen in the past?

Next: How Does Global Warming Affect the Arctic?

Have you heard about changes in the Arctic attributed to global warming? In your notebook, record some reasons why you might be concerned about what is happening there. For some ideas, think about recent news reports and films.

Next: Data Sets

Data sets are collections of observations obtained through surveys (such as the observations by local residents) or instruments (such as satellite measurements). Scientists look for patterns within data sets to help them formulate research questions. To explore these questions, scientists often develop predictions and then design ways to test whether they are valid.

Next: Inuit Observations

The Inuit peoples of the Arctic have been passing down climate observations from generation to generation. Their daily lives depend heavily on their natural environment, whose material resources provide them with food, clothing, and shelter. Sharing these observations is essential to the success and survival of their culture. Recently, however, their understanding of their surroundings has been challenged by observations that have no precedent in their thousand-year history.

Observed data of this type, which are not collected by instruments, are called qualitative data. Although qualitative data cannot be compared mathematically, they can be highly informative for anyone studying climate change.

Next: The Weather at Banks Island

Sachs Harbour on Banks Island is located along the Western Arctic coast of Canada. The Inuit who live there—the Inuvialuit—have observed changing weather factors that indicate long-term climatic trends. As their climate and physical surroundings change, the Inuvialuit are finding ways to adapt and thereby protect the future of their culture.

Watch the Inuit Observations of Climate Change QuickTime Video.

In your notebook, jot down some of the ways that climate change is affecting the lives of the Sachs Harbour community.

Next: Observe Changes on Banks Island

Next: Relate the Arctic to You

With your partner, discuss these questions:

1. Were you surprised by any of the connections made by the Sachs Harbour residents between various weather factors and their observed changes to their surroundings? If so, which ones stood out?
2. What were some of the adaptation strategies that the residents discussed in response to the changes in the weather pattern?
3. Ice is critical to people who live in the Arctic. What significant aspects of your region may be affected by climate change? Jot down your ideas in your notebook. You will have a chance to explore them later in the activity.

Before continuing, discuss with the class some of the strengths and shortcomings of qualitative data.

Next: Satellite Observations

Satellite-based sensing and imaging technologies cannot record the impact that climate change has on a people's way of life, but they can provide a numerical understanding of what is happening in an area being studied. We call data that are collected by instruments and can be compared mathematically quantitative data.

Satellite observations can comprise data from multiple readings, giving scientists the ability to make broad evaluations—for example, gauging the impact of climate change over time throughout the entire Arctic region.

In the next part of this activity, you will be working with visualizations made from satellite data. As a class, begin by watching the Earth System: Satellites QuickTime Video. Then, discuss the following questions:

• In what ways do satellites affect your life?
• What kinds of data do scientists gather via satellite?

Next: Arctic Sea Ice Visualizations

Next: Examine Satellite Data

You will now have a chance to make your own analysis of changes in Arctic sea ice using visualizations from NASA satellite data. With your partner, select one of the following questions to investigate:

1. Has the maximum extent of sea ice in the Arctic changed over the past 25 years?
2. Have there been any changes in when Arctic sea ice breaks up each spring over the past 25 years?

Now go to the Arctic Sea Ice Satellite Observations Flash Interactive. If you selected question 1, go to the "March 1982–2007" tab. If you selected question 2, go to the "June 1982–2007" tab. Play the animation (several times, as needed) to see how the sea ice has changed during this 25-year time span. You can also look at the individual years, and compare 1982 and 2007 using the "Show Comparison 1982 & 2007" button.

After viewing the selected animation, discuss with your partner any significant changes you observed. Record your findings in your notebook.

Next: Measure the Sea Ice

Depending on which month you focused on in the interactive activity, print out the Arctic Sea Ice Map: March 1982–2007 PDF Document or the Arctic Sea Ice Map: June 1982–2007 PDF Document. Follow the instructions below:

March 1982–2007

• Select one of the following regions to look at more closely:
  • North Bering Sea
  • Greenland
• Estimate the difference in maximum sea ice coverage between the 1982 and 2007 visualizations.
• The printouts will assist you in making your calculations. Count the number of grid squares covered by sea ice in your chosen region for each year, then calculate the difference between the two years. Each square represents 10,000 sq km.

June 1982–2007

• Select one of the following regions to look at more closely:
  • Banks Island, Canada
  • Novaya Zemlya, Russia
• Using the printouts to assist you, mark any areas where you notice changes in spring breakup of the ice between the two years. Specifically, highlight places on either map where ice was present in one year, but not in the other. You can also refer back to the Arctic Sea Ice Satellite Observations Flash Interactive to identify places where the ice concentration has changed.

When you have finished, record your findings in your notebook. Does this quantitative data support or fail to support the qualitative data based on the Inuit observations?

Next: Propose an Answer

Copy your findings to a chart in your classroom (one chart per region). Give everyone a chance to look at the different class findings, and then use the chart data as the basis for a class discussion of the following questions:

1. Do any data sets appear to show change over time?
2. Based on the data, what claims can you make about change in sea ice coverage and spring breakup over time? Be sure to include your evidence.
3. If the data show change over time, can you think of any possible explanations other than climate change?
4. If a distinct trend is not apparent, does this mean the Inuit observations from the video are essentially wrong or less scientific? Why or why not? Be sure to explain your reasoning.
5. What can scientists learn from "Native ways of knowing" (e.g., Inuit observations)?

Next: Is the Climate Changing in My Community?

In this investigation, you will gather responses to your own class survey on climate observations in your community.

Begin by working in small groups to design a survey based on the Inuit Observations of Climate Change video and the Banks Island observations chart. Make a list of questions that might be useful to assess what your community has experienced with respect to changes in weather and, over the longer term, climate. (Note: You may refer to the Observations Chart in the next section to help you design your survey questions.)

When all of the small groups are finished, share your questions with the class. As a class, decide which ones to include in the final version and agree on a response format (e.g., a written or verbally administered questionnaire).

Finally, go out into your community and conduct the survey. Be sure to involve people of different ages to get a broader variety of observations. You should restrict your survey to people you know well, such as friends, family members, and neighbors.

Next: Make a Data Set from Your Community Observations

Next: What Do the Survey Data Say?

Next: For Further Exploration