Part B: Climate Change: Trends and Indicators
Source: NCAR Image Library
So far in this module, you have studied the many factors that influence weather and climate, and you have considered the life experiences of a 300-year-old maple tree in Vermont. In this lab, you will develop an understanding of how the climate is changing and what this future climate has in store for plants, people, and the planet.
To begin, view the 3-minute video clip Introduction: Why study climate change?.
After you have watched the video, answer the Checking In questions, below.
- What are the symptoms (or indicators) of climate change described in this video? Remote Sensing observations of melting sea ice, thermometer records of soils and ocean, changes in the budburst (phenology), changes in the timing of the freezing of rivers and lakes.
- How do scientists observe the planet? List three methods that you saw or heard about in the video. Scuba diving, microscopic observations, satellite observations.
- How likely is the warming outside of the normal range, of at least the last 1000 years? Very Likely, which means that scientists are 99% certain.
What is climate change? Frequently Asked Questions
After watching the introductory video, review some basic facts about climate change, by matching questions and answers about climate change.
- Download and print this scrambled set of Frequently Asked Questions (FAQs) (Acrobat (PDF) 123kB Apr18 12) about climate change.
- Cut the questions and answers into strips and sort them into two stacks.
- Work with your lab team or class to match the questions with the correct answers. After you have them sorted, review the information given in these questions and answers. When you are finished you should have a good sense of climate change basics.
Global clues of change
Now that you have a sense why scientists are studying climate change, you will use the interactive, below, to examine recent indicators (from the past 150 years) showing other dramatic changes in Earth's vital signs.
- On the interactive image above, click the Air Temperature over Land button to get an overview of how temperature has changed.
- Then, on the overview page, click the Data button in the lower right to view the graphs of temperature change over the past 100-150 years.
- You will see that the temperature data is displayed as an anomaly Anomaly: a difference from the baseline or long-term average. In this case, the baseline average is the average temperature for the period 1951-1980.
Anomaly calculations and graphs help to focus our eyes on the difference from average. For example, doctors have charts against which they compare your height and weight so that they can tell you if you are above or below average height as compared to other people your age. This type of data display helps scientists to more clearly illustrate the evidence of a change or difference. Close the window when you are done looking at the graphs.
- Read a short article explaining why global temperature is graphed as an anomaly, and view an interactive graph on this page: Climate Change: Global Temperature
- Select and read the information, about 3-5 more indicators of your choosing.
- After viewing the interactive and data trends graphs, answer the following Stop and Think questions.
Stop and Think
- Define anomaly in your own words. What does it mean to be different than average?
- What is the trend in average global temperatures?
Indicators of change in the United States
As you can see from the interactive, there are many indicators of climate change that scientists are carefully observing. Viewed together, these indicators give scientists a complete picture of the diversity and magnitude of the changes taking place on our planet. In this next activity, you are going to become an expert on one indicator and then share your knowledge with your class while looking for correlations and connections between the data.
- To begin, choose one indicator from the list below and dig a little deeper into the trends shown by that indicator. Climate Change Indicators:
- U.S. and Global Temperature
- Heat Waves
- U.S. and Global Precipitation
- Heavy Precipitation
- Tropical Cyclone Intensity
- Ocean Heat
- Sea Surface Temperature
- Sea Level
- Ocean Acidity
- Arctic Sea Ice
- Lake Ice
- Snow Cover
- Heat-Related Deaths
- Length of Growing Season
- Plant Hardiness Zones
- Leaf and Bloom Dates
- Bird Wintering Ranges
- After you have chosen an indicator, use the website provided below to download and print a booklet with information. (Note: your teacher may assign you an indicator and give you a printed copy of the indicator information to work with.) U.S. Environmental Protection Agency (EPA) Climate Change Indicators Once on the web page, scroll down to download the full report, or sections of the report that you are interested in. (Report is in PDF).
- Work as a lab group to understand the data trends and to look for relationships between the climate change indicator data and the global temperature trend. As you are working, complete the following tasks and record your notes in your lab notebook:
- Record the title of indicator that you are studying.
- Write four statements and a question about the graphs, trends, and indicators.
- Design a simple symbol or icon to represent the data set.
- List and describe possible two impacts that could be a result of the trend (i.e., a warming ocean could result in more heavy rain).
- Brainstorm why these impacts matter. In other words, how it might affect your life or the lives of other plants, animals, or society. Below are some possible categories to include in your impact analysis:
- Water supply
- Plants, animals, ecosystems
- Once you have analyzed one indicator, and completed the tasks listed above, pair with another team and share your insights and questions.
- Return the printed materials to your teacher and gather as a class to share the indicators of climate change slide show. The slide show is linked here: U.S. Environmental Protection Agency (EPA) Climate Change Indicators. It is also available as a PDF file from this site.
- After watching the online slide show, build a tentative concept map of correlations and connections between the different indicators. Start your connections circle with the central circle or idea: Greenhouse gases absorb radiation causing a warmer atmosphere. Draw arrows to other bubbles that list the effects of warmer atmosphere, such as a warmer ocean, or melting polar snow and ice.
Stop and Think
3. List three indicators of climate change that you examined, either using the printed or online materials, and describe the trends that are shown by each indicator.