energy & the environment · human impact on the environment has rapidly increased in modern...

PARC

ENERGY &THE ENVIRONMENT

PARC Energy and the Environment Kit #3: Investigating Climate Change

Table of Contents

Topic Template …………………………….………………………………………………………….. 1

Kit Materials List …………………………………………………………………………………………..…. 2

Investigating Climate Change: The Big Idea, Why & Background ……….……..…………. 3

Activity 1 - Climate Chat …………………………………………………………………………………… 5

Activity 2 - Agree/Disagree ………………………..…………………………………………………….. 7

Activity 3 - Carbon Passport Game ……………………………………………………………………. 9

Activity 4 - Tree Rings: Living Records of Climate ……………………………………………… 25

Activity 5 - Ice Cores: Exploring the History of Climate Change ………………………….. 39

Extension - Qualitative and Quantitative Ice Core Lab Analysis …………………………… 45

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Topic Template Topic Title Investigating Climate Change Associated Curriculum Energy & the Environment Associated Content

The Carbon Cycle, Tree Ring Analysis, Ice Core Sampling, Evidence-based Support

Recommended Grade Level(s)

Upper Elementary, Middle School and High School – Grades 6-12

Materials Needed PARC Energy & the Environment Kit #3: Climate Change Teacher Must Provide:

• Classroom computers with internet access • Sample particulate matter for ice core samples, access to a freezer • Mass balances • Tape, scissors, stapler • Copies of student worksheets

• Summary § Discuss concepts about climate change and environmental responses to fluctuations in carbon dioxide emissions

§ To what extent has human activity modified the environment? § How do scientists study climate patterns and make conclusions

based on authentic geoscience data? § Analyze geoscience data from NASA such as precipitation and

temperature patterns over time and compare to tree ring growth § Design a procedure to test ice core samples for particulate matter

and determine what would cause variable quantities of each Related NGSS Standards Interactions, Energy, and Dynamics Earth and Human Activity

MS-ESS3-4 Construct an argument supported by evidence for how increases in human population and per-capita consumption of natural resources impact Earth's systems. MS-ESS3-3 Apply scientific principles to design a method for monitoring and minimizing a human impact on the environment. HS-ESS3-5 Analyze geoscience data and the results from global climate models to make an evidence-based forecast of the current rate of global or regional climate change and associated future impacts to Earth systems. HS-LS2-5 Develop a model to illustrate the role of photosynthesis and cellular respiration in the cycling of carbon among the biosphere, atmosphere, hydrosphere, and geosphere.

Background/Why

Human impact on the environment has rapidly increased in modern times. Scientists can monitor and minimize climate disruption by analyzing geoscience data to determine the cause and effect of carbon emissions. The flow of energy into and out of Earth’s systems result in climate change.

Activity 1 Climate Chat Activity 2 Agree/Disagree Discussion Activity 3 Carbon Passport Game Activity 4 Tree Rings: Living Records of Climate Activity 5 Ice Cores Lab: Explaining the History of Climate Change Extension Qualitative and Quantitative Ice Core Data Analysis

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PARC Energy and the Environment Kit #3: Investigating Climate Change

Materials Included in Kit

Ø 1 Copy Climate Change Unit Module Lesson Plan Activity Title Item Qty Unit Distribute 1: Climate Chat Copy Master: Climate Chat 1 Each Copy 1 per group 2: Agree/Disagree Discussion Station Cards (4), laminated 1 Set For the class

3: Carbon Passport

Copy Master: Passport Cover 1 Each ½ sheet per student Copy Master: Station Questions 1 Each 6 @ ½ sheet per

student Copy Master: Travel Diary 1 Each ½ sheet per student Station Signs (10), laminated 1 Set For the class Bingo Daubers 10 Each 1 per station Dice 10 Each 1 per station

4: Tree Rings

Copy Master: Tree Ring Analysis Worksheet

1 Each Copy 1 per student

Tree Ring Images (4), laminated • Boston, MA • Jackson, MI • Columbia, MO • Seattle, WA

6 Set 1 set per group of 4 students

Tree Ring Data Sets (4), stapled • Boston, MA • Jackson, MI • Columbia, MO • Seattle, WA

6 Set 1 set per group of 4 students

5: Ice Cores Lab

Copy Master: Ice Core Research Student Assignment

1 Each Copy 1 per student

Food Coloring, set of 4 1 Set For teacher prep Ice Core Mold, with caps 6 Each For teacher prep Carbonated / Sparkling Water 1 Can For teacher prep Vinegar, 16 oz bottle 1 Each For teacher prep pH Paper, [range], box 3 Each Share among groups Ruler, 12 “ 6 Each 1 per group Graduated Cylinder, 50 mL 6 Each 1 per group Paper or Plastic Cups 30 Each 5 per group Miter Box with Saw 3 Each Share among groups Plastic Trays 6 Each 1 per group Coffee Filters 30 Each 5 per group

Ext: Ice Core Data Analysis No materials provided

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Investigating Climate Change Adapted from the Next Generation Science Standards, 2013; and the US Department of Energy, Carbon Dioxide Information Analysis Center (CDIAC) The Big Idea: Discipline Core Ideas in the Framework for Science Education (NGSS, Final, July 2013) ESS 3: Human activities, such as the release of greenhouse gases from burning fossil fuels, are major factors in the current rise in Earth’s mean surface temperature (global warming). Reducing the level of climate change and reducing human vulnerability to whatever climate changes do occur depend on the understanding of climate science, engineering capabilities, and other kinds of knowledge, such as understanding of human behavior and on applying that knowledge wisely in decisions and activities. LS 2:Photosynthesis and cellular respiration are important components of the carbon cycle, in which carbon is exchanged among the biosphere, atmosphere, oceans, and geosphere through chemical, physical, geological, and biological processes.

In this learning module, students will analyze geoscience data and the results from global climate models to make an evidence-based forecast of the current rate of global or regional climate change and associated future impacts to Earth's systems. Examples of evidence, for both data and climate model outputs, are for climate changes (such as precipitation and temperature) and their associated impacts (such as on sea level, glacial ice volumes, or atmosphere and ocean composition). WHY? Accelerated global climate change is a uniquely modern crisis. Technological development over the past century has led to a quantifiable increase in carbon emissions in our pursuit for energy to power our growing population’s demands. Students will ask questions to clarify evidence of the factors that have caused observable changes in regional climate patterns.

Through computer simulations and other studies, important discoveries are still being made about how the ocean, the atmosphere, and the biosphere interact and are modified in response to human activities. Empirical evidence is required to differentiate between cause and correlation and make claims about specific causes and effects. Current models predict that, although future regional climate changes will be complex and varied, average global temperatures will continue to rise.

The outcomes predicted by global climate models strongly depend on the amounts of human-generated greenhouse gases added to the atmosphere each year and by the ways in which these gases are absorbed by the ocean and biosphere. Change and rates of change can be quantified and modeled over very short or very long periods of time. Some system changes have been found to be irreversible.

Scientific knowledge can reveal what has happened throughout the history of the Earth, as well as what could potentially happen. Analysis of geoscience data with the assistance of computational models is essential to form options for our impending behavior. This valuable information can be used, alongside ethical and cultural principles, to inform human decisions that will shape the future of all life on Earth.

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Background: Modern society has relied largely on fossil fuels to meet the energy demands for a growing human population. Carbon dioxide is released into the atmosphere as a result of a basic combustion reaction that requires a hydrocarbon fuel, such as conventional oil. The gasoline used to power cars is derivative of the conventional oil refinement process, and contributes to global carbon emissions. We now know that carbon released in the form of carbon dioxide plays a part in retaining excess heat within our Earth’s atmosphere. This phenomenon has a fundamental impact on Earth’s systems such as the hydrosphere, atmosphere, cryosphere, geosphere, and biosphere. An example of the far-reaching impacts from a human activity is how an increase in atmospheric carbon dioxide results in an increase in photosynthetic biomass on land and an increase in ocean acidification, with resulting impacts on sea organism health and marine populations. Though the magnitudes of human impacts are greater than they have ever been, so too are human abilities to model, predict, and manage current and future impacts. Cause and effect relationships can be used to predict phenomena in natural or designed systems.

The impact of global climate change is far-reaching. It is necessary to evaluate sources of data for their accuracy so society can make decisions based on facts instead of desired outcomes. Oral and written arguments must be supported by empirical evidence and scientific reasoning to support or refute an explanation or a model for a phenomenon or a solution to a problem.

Ice core sampling is a reliable method to obtain long-range climate data that scientists can use to determine a cause and effect relationship between biogeochemical processes and atmospheric composition over time. The presence of carbon molecules in ice, such as carbon dioxide and methane, can inform scientists about the conditions of Earth over longer periods on the geologic time scale. The oldest ice cores that have been obtained to date are over 800,000 years old and reveal fluctuations in key atmospheric gases. The ice cores are extracted from deep within glacial ice structures and the oldest layers are found at the deepest layer of the core. Tree ring analysis is another useful method to determine temperature fluctuations and precipitation amounts over time. The banding patterns of the tree rings can be compared to geoscience data such as temperature and precipitation to determine overall climate patterns for a given region.

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ACTIVTY 1: Climate Chat Adapted from Get Real on Climate: Climate Change Lesson Plans for grades 9-12 and published by UNICEF Canada to accompany the Get Reel on Climate Competition 2009 Background Students will have varying levels of exposure to climate science before they get to middle school and high school. Some may be very familiar with current scientific literature on the topic, and others may be completely unaware of the connection between humans and the environment. Most will fall somewhere between these two extremes. Start a conversation about climate change before beginning a unit on the topic. This can be done effectively by allowing students to share their current level of comprehension and then defending their position. Most students understand that evidence-based arguments enlighten us on current climate patterns and the mechanisms that modify them from their typical state. Materials Photocopy one “Climate Chat Questions” handout per group (This lesson suggests 2 groups, but you can change group numbers if needed to suit your classroom) Clear a large space in room for students to get up and move around Instructions 1. Explain that today the class is going to have a chat on climate change. Organize the students into two equal-sized groups. Join the chat if you have odd numbers. 2. Give each group one Climate Chat Questions handout and assign them a specific question per each student within each group. Instruct students to have a pencil/pen and paper. 3. Have the students read their assigned question to themselves. Explain they will ask this question of everyone in the room and they need to design a chart or list to record each person’s answer. 4. Instruct them to first ask their assigned question to each person within their group and record the responses. After some time, have the groups ask the same question to each person in the other group and record responses. 5. Have each student compile the data they collected and create a simple chart or graph to convey the results of their questions. 6. Then have students contribute the best of the anecdotal comments they collected to a communal climate change “graffiti wall” (this can just be a space in the room they can write such as a whiteboard or easel paper taped to a wall). They can contribute drawings, graffiti tags, quotes, etc. in addition to the comments. 7. Display the charts/graphs and graffiti wall around the room. Have students walk around to see the results. Discuss Did you find your peers to have strong feelings or ideas about climate change? Is this a topic that seems to interest you as a group? Were there similar levels of understanding about climate change? Did anything surprise you about the results? Extension Have students draft a creative campaign to raise the level of awareness and understanding of climate change in their school. What would they call the campaign? What creative tactics would they use to get staff and students interested? What resources/support would they need to implement it? Based on their Climate Chat findings, what aspects of climate change should the campaign focus on? For ideas, have students visit www.uniteforclimate.org to see examples of youth campaigns that tackle climate change.

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Do you believe the earth is currently in a period of climate change Do you discuss climate change with your friends? (i.e. warming temperatures, more extreme weather events, etc.)?

Yes, often. Hardly ever. Yes. No. Maybe, I’m not sure. Sometimes. Never.

How would you rate (on a scale of one to five) your understanding of How familiar are you (on a scale of one to five) with ways that you climate change? personally can impact climate change, for better or worse?

1 – Corresponds to being completely unfamiliar with climate change. 1 – Corresponds to being not at all familiar. 5 – Corresponds to being an expert on climate change. 5 – Corresponds to very familiar.

The Intergovernmental Panel on Climate Change says there is now How often would you say you consider the impact your lifestyle has undeniable evidence that climate change is caused by humans. How on the world’s climate? do you feel about this?

Daily Monthly Yearly Never I agree fully. I’m still not sure. I think they are wrong.

A Native American proverb says that “We do not inherit the earth Would you say that media stories on climate change have caused from our ancestors, we borrow it from our children.” Do you agree you to change any of your behaviours? with this proverb? Why or why not?

Yes. I have made changes as a result of media on climate Yes. Comments:______________________________________ change.

Maybe a No. Comments:_______________________________________ No. The media has not influenced my behaviour in this regard.

No. I’m unfamiliar with the concept of climate change. Somewhat. Comments:_________________________________

Do you and your family discuss climate change? Do you have an interest in learning more about climate change?

Yes. We are concerned and we discuss it often. Yes, definitely. Sometimes. Maybe, depends on the topic. Hardly ever. No, I have no interest. Never.

If you could address world leaders on climate change, what would How often do you use public transit, walk or bike instead of driving in you say? a personal vehicle to reduce your carbon footprint?

Comment:______________________________________________ Never. I always choose to drive/be driven in a personal vehicle. _______________________________________________________ A few times a year. _______________________________________________________ A few times a month. _______________________________________________________ A few times a week. _______________________________________________________ Daily

Do you discuss climate change online (i.e. chat rooms, blogs)? Do you feel that your school should try to address climate change?

Yes, often. Hardly ever. Yes. No. Sometimes. Never.

Does your family use CFLs instead of incandescent light bulbs? Have you ever participated in an online campaign against global

climate change? Yes. No. Sometimes. I don’t know. What are those? Yes. No.

Climate Chat Questions There are 18 Climate Chat questions. Add to or remove from them depending on the size of your class.

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ACTIVTY 2: Agree/Disagree Discussion Background Students will come into a unit on global climate change with some misconceptions and personal opinions that may or may not be supported by climate science. It is important to address these misconceptions objectively and allow students a chance to change their minds, given authentic geoscience data and factual evidence. This activity will give students the opportunity to hear from other students as well as construct their own evidence-based arguments about climate change. Materials Create four signs (can be on standard size paper or larger paper if available, or you can use the example station cards provided) that read: “Agree” “Disagree” “Strongly Agree” “Strongly Disagree” Before you begin… Display or tape the Agree/Disagree/Strongly Agree/Strongly Disagree signs around the room Instructions 1. Point out to your students the Agree/Disagree/Strongly Agree/Strongly Disagree signs around the room (you can put the signs in the corners of the room) or all along the same wall if there is enough space. 2. Explain to the students that you will read a statement and they have a moment to decide if they Agree, Disagree, Strongly Agree, or Strongly Disagree with that statement. Refer to the “Agree/Disagree Statements” section to give you some ideas to get started. 3. Have them stand under or near the sign that best reflects their opinion about the statement. Tell them that it is okay to be in between signs if that matches how they feel about the statement. 4. Once students have made a decision and are standing by their sign, have them discuss with the person standing next to them why they chose that spot. You can also have students from opposite ends (Strongly Agree and Strongly Disagree) share their opinion and why they chose what they did. 5. Read the next statement and ask them to move again. Repeat the discussion until all statements have been discussed. Agree/Disagree Statements

• Earth’s polar regions will always be frozen and icy • Greenhouse gases are always bad for the environment • A small temperature increase may have a great effect on Earth’s ecosystems • If we were able to stop all carbon dioxide emissions, Earth’s average temperature would

decrease • Human activity is the only cause of climate change • Current global warming trends can be fully explained by the natural cycles of Earth • Average global temperature increase can be stopped with human intervention • Increased global temperatures may result in the flooding of many cities • An increase in the carbon dioxide level of the atmosphere is heating the planet

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Agree

Strongly Agree

Disagree

Strongly Disagree

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ACTIVTY 3: Carbon Passport Game Adapted from ”The Incredible Journey”, Project WET Background Carbon atoms circulate through the Earth’s ecosystems. The carbon atom itself does not change as it moves through these processes. However, a single carbon atom can form chemical bonds with other elements such as hydrogen or other carbons to become entirely different molecules. The circumstances that allow this to happen are statistically random. For example, a single carbon atom might join with an oxygen gas diatom to become carbon dioxide in the process of cellular respiration. That carbon dioxide molecule may be released into the atmosphere only to bond with a water molecule to become carbonic acid which can then come back down to Earth in the form of acidic-pH rain. Carbon atoms are truly “world travelers” in the sense that they can journey around the Earth through this process of constant molecular reformation for eternity. Wouldn’t it be interesting to follow a single carbon atom along as it undergoes countless chemical reactions? The carbon atoms that were ingested by the dinosaurs eventually became fossil fuels and were eventually refined into the gasoline we are still powering our vehicles with today. This is the concept we will focus on during this Carbon Passport Game. Students will travel from station to station as they (the carbon molecule) undergo different chemical processes. The big idea here is for students to notice that the carbon atoms must go somewhere, they can’t disappear entirely. Students will start to grasp the idea that carbon emissions, especially carbon dioxide, never really go away. Those carbon atoms will continue to cycle through the Earth’s geochemical processes. In light of global climate patterns, this basic concept of the carbon cycle will be helpful for students to determine methods to decrease fossil fuel consumption and reduce carbon emissions. Materials Kit provides:

• Carbon Passport Copy Masters • Carbon Cycle 10 Station Signs,

laminated • 10 Bingo Daubers • 10 Dice

Teacher provides: • Tape • Student Copies-Carbon Passport • Scissors • Stapler

Before you begin… Set up the Carbon Passports by photocopying the master copies (provided here). Each passport gets one passport cover, 6-8 copies of the station questions (can photocopy double sided), and one copy of the travel diary. Assemble the passport by cutting the copied papers in half, arranging the pages into order, folding them into a booklet, and stapling the papers together on the spine of the passport booklet. Students can cut and assemble their own passport booklet if copies of the pages are made ahead of time. Before the game starts, have the Carbon Cycle Station Signs (provided here-must be printed single-sided) taped up around your classroom, there is no particular order. Students need to be able to read the signs to follow the directions, so make sure you tape them at eye level for your students. At each station, set out one die and a bingo dauber (or alternately a rubber stamp and ink stamp pad), so students can use them to stamp their carbon passports.

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Instructions 1. Explain to your students that they will model different stages of the Carbon Cycle today. They will do this by “becoming a carbon atom” that will travel to different ecosystems on Earth, and they will record their trip in their “Carbon Passport”. 2. Distribute the Carbon Passports, one to each student. If the passports haven’t been assembled yet, have your students cut them apart and put them together, if time allows. Instruct them to put their name on their passport. 3. Point out the carbon station signs you have put up around the room. Explain to your students that they will start at a random station of their choosing. They will write in their passport to document where they (the carbon atom) travel to and from. 4. Have them begin the game by going to a random station and following the direction on the station sign. Each station will direct them to roll dice and the number the die lands on will determine what happens to their carbon atom and the following station they will go to. 5. Remind them to document the stations they visit and stamp their passport. They are also required to answer the questions on their passport document for each station. 6. Give them 20-30 minutes (or longer for a bigger group) to go through the stations. They will start to notice that they get stuck in a loop… as in, they keep rolling the dice and keep going back to the same stations after awhile. Explain that they may not get to every single station throughout the course of the Carbon Cycle, and that’s normal. Have them continue to document their trips, even if they are going back to the same stations. This is part of the carbon cycle and it is important for them to know that a single carbon atom may go through different stages of the carbon cycle multiple times, or some stages not at all. 7. Once the game is over, have them come back to their seats to discuss their findings and complete the (optional) assessment. 8. Use the discussion questions provided to ask your group comprehension questions to explain what they discovered during the game. Discuss What did you notice about your carbon travels? Any patterns? Did you get stuck in a “loop”, and if you did, why do you think this happened? What processes can you identify that represents pathways for carbon to travel? (Answers might include photosynthesis, cellular respiration, carbon emissions from fossil fuels, evaporation, transpiration, surface runoff, decomposition, plants/animals being eaten by other organisms, etc.) Where there any stations you did not roll the dice to? Why do you think this happened? Assessment After students have completed the Carbon Passport Game, assess their understanding of the carbon cycle. You will need to provide standard size white copy paper and colored pencils, markers, crayons, etc. Instruct them create a “postcard” of their carbon travels that summarizes the carbon stations they visited, how the “carbon atom” got there, and the next station it went to from there. Encourage students to be creative – they can develop a story of the entire trip and write the text of the postcard to a friend or family member. On the other side of the “postcard”, have them draw a schematic diagram or picture of how their carbon atom moved through the carbon cycle. Assess their postcards on accuracy of information about the carbon cycle and creative effort.

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Atmosphere

Stamp your passport, then roll the die to see where you will

travel next.

If your die reads: Odd numbers (1, 3, or 5) You diffuse into the water and become part of the surface water. If your die reads: Even numbers (2, 4, or 6) You are removed from the air in photosynthesis to make up a plant.

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Surface Water

Stamp your passport, then roll the die to see where you will travel next.

If your die reads: 1 or 2 You move and circulate through the water until you reach the deep ocean.

If your die reads: 3 or 4 You evaporate and enter the atmosphere. If your die reads: 5 or 6 Through photosynthesis, you are taken in by marine life.

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Deep Ocean


If your die reads: Odd numbers (1, 3, or 5) You move and circulate through the water until you reach the surface water. If your die reads: Even numbers (2, 4, or 6) Through photosynthesis, you are taken in by marine life.

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Plants


If your die reads: 1 Forest fire! You burn and are released into the atmosphere.

If your die reads: 2 or 3 You die and decay into the ground. You are now part of the soil. If your die reads: 4 or 5 You get eaten and become part of a land animal.

If your die reads: 6 You die, then decay into the ground where you remain for millions of years until you turn into a fossil fuel.

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Marine Life


If your die reads: 1 or 2 You are eaten and become part of a land animal. If your die reads: 3 When you die, your decomposed body is distributed throughout the surface water. If your die reads: 4 When you die, your decomposed body becomes distributed throughout the Deep ocean. If your die reads: 5 or 6 After you die, you collect on the ocean floor with other marine life and bcome part of the soil.

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Soils


If your die reads: Odd numbers (1, 3, or 5) You are consumed by microorganisms.

If your die reads: Even numbers (2, 4, or 6) The living matter in your soil is stored for millions of years and converted into fossil fuels.

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Fossil Fuels

Stamp your passport, then roll the die to see where you will

travel next.

If your die reads: 1 or 2 You are burned and released into the atmosphere.

If your die reads: 3 or 4 You dissipate into the deep ocean. If your die reads: 5 or 6 You are taken in by microorganisms

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Microorganisms


If your die reads: 1 or 2 You die and your remains become part of the soil.

If your die reads: 3 or 4 You are eaten and taken in by marine life. . If your die reads: 5 You are eaten and taken in by land animals. If your die reads: 6 You are excreted and become part of animal waste.

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Animal Waste


If your die reads: 1 or 2 Over time, you break apart and become part of the soil.

If your die reads: 3 You are eaten and become part of a land animal.

If your die reads: 4 You are burned and become part of the atmosphere. If your die reads: 5 You are eaten and taken in by microorganisms. If your die reads: 6 You are excreted and become part of animal waste.

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Land Animals


If your die reads: 1 or 2 The animal you are in defecates and you become animal waste.

If your die reads: 3 or 4 The animal you are exhales you as carbon dioxide and you become part of the atmosphere. . If your die reads: 5 or 6 The animal you are in dies and you decay into soil.

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Carbon Passport

Citizen of Planet Earth Your name:

"

Carbon Passport

Citizen of Planet Earth

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Your name: Station: ________________ Stamp:

What happened to the carbon atom at this station?

Roll the die again. Which number did you get?

Memory of this visit:

Visit the next station to see where the carbon atom (you) goes to next!

" Station: ________________ Stamp:





Station: ________________ Stamp:





Station: ________________ Stamp:





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Travel Diary:

How many stops did you make on your journey? How many stops could you make on your trip? Was your journey the same as other students’ trips? Why or why not? Write a paragraph about your trip, describing where you are and how you got there.

Story Snippet:

"

Travel Diary:

How many stops did you make on your journey? How many stops could you make on your trip? Was your journey the same as other students’ trips? Why or why not? Write a paragraph about your trip, describing where you are and how you got there.

Story Snippet:

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ACTIVITY 4: Tree Rings: Living Records of Climate This activity has been adapted from the United States Environmental Protection Agency (EPA), in conjunction with National Aeronautics and Space Administration (NASA) from www.epa.gov/climatestudents Students will: • Analyze tree rings to draw conclusions about precipitation patterns in the past • Compare their own analysis with actual precipitation data (from NASA) to determine similarities and

differences in precipitation patterns gathered over a given time period • Learn how scientists gather information about the Earth’s past and present weather and climate • Understand how past climate patterns can help us understand the changes we are experiencing

today • Use these data to help understand what the climate was like at a particular location in the past Background This activity provides context for understanding how scientists can examine natural materials such as trees to learn about climate conditions in the past, before widespread measurement of temperature and rainfall. Scientists use a variety of methods to collect data about the Earth’s weather and climate. Weather stations, balloons, buoys, and satellites help researchers gather information about Earth’s current weather conditions. Scientists learn about Earth's climate in the past by studying historical records as well as clues that remain in rocks, ice, trees, corals, and fossils. These clues not only tell us how the Earth’s climate has changed, but they can also help scientists understand why these changes came about. Knowing how the Earth’s climate has changed over time can help scientists determine whether the changes that are occurring now are part of the Earth’s natural pattern or caused by human activities. One way scientists are learning about past climate is by studying tree rings. This field of research is known as dendrochronology. Scientists can use tree rings to measure the age of a tree and learn more about the local climatic conditions the tree experienced during its lifetime. In temperate areas, like most of the United States, trees only grow during the part of the year called the growing season. The length of this growing season depends on the climate in a particular location. During each growing season, the trunk of the tree grows thicker, producing a layer of new wood called a tree ring. It’s possible to see the boundary between one ring and the next because of differences in the color of the wood. Early in the growing season, trees grow relatively quickly and produce less-dense, paler wood. Near the end of the growing season, they produce more dense, darker wood. Trees generally grow more during wetter growing seasons with favorable temperatures, forming wider rings. Narrow rings may be caused by stressful periods such as droughts. Although tree rings only record conditions during the growing season (in other words, not during the winter in most of the United States), droughts can build up over many months or even many years, so a lack of rain or snow in the winter can lead to poor growing conditions in the spring.

Tree ring patterns provide information about precipitation and other conditions during the time the tree was alive. Scientists can learn even more about precipitation and temperature patterns by studying certain chemicals in the wood. Modern trees can be interesting to compare with local measurements (for example, temperature and precipitation measurements from the nearest weather station). Very old trees can be even more interesting because they offer clues about what the climate was like before measurements were recorded. In most places, daily weather records have only been kept for the last 100 to 150 years. Thus, to learn about the climate hundreds to thousands

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of years ago, scientists need to use other sources such as trees, corals, and ice cores (layers of ice drilled out of a glacier or ice sheet—mostly in Greenland and Antarctica). By studying tree rings and other clues in our environment, scientists have learned that there have been times when most of the planet was covered in ice, and there have also been much warmer periods. In general, climate changes prior to the start of the Industrial Revolution in the 1700s can be explained by natural causes, such as changes in solar energy and volcanic eruptions. Recent climate changes, however, cannot be explained by natural causes alone. Instead, human activities are very likely responsible. Tree rings alone cannot tell us whether human activities are responsible, but they do help by revealing patterns that scientists can investigate further.

A tree adds a new layer of wood every year, called a tree ring. Scientists examine these rings to learn about past climate conditions. Variables such as temperature and precipitation can be determined by analyzing the tree rings. Climate data can be used to compare to actual trees in a given region to study long-term climate patterns over time. Image source: U.S. EPA, A Student’s Guide to Global Climate Change website

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Climate: The average weather conditions in a particular location or region at a particular time of the year. Climate is usually measured over a period of 30 years or more.

Climate change: A significant change in the Earth’s climate. The Earth is currently getting warmer because people are adding heat-trapping greenhouse gases to the atmosphere. The term “global warming” refers to warmer temperatures, while “climate change” refers to the broader set of changes that go along with warmer temperatures, including changes in weather patterns, the oceans, ice and snow, and ecosystems around the world.

Precipitation: Rain, hail, mist, sleet, snow, or any other moisture that falls to the Earth.

Tree rings: Trees add a new layer of wood every year. When you cut across the trunk, each layer looks like a ring. Each ring represents one year. Rings generally grow wider in warm, wet years and thinner in cold, dry years. Tree ring records can go back hundreds to thousands of years, depending on when the tree lived and how old it was. Scientists examine tree rings to learn about past climate conditions. Weather: The condition of the atmosphere at a particular place and time. Some familiar characteristics of weather include wind, temperature, humidity, atmospheric pressure, cloudiness and precipitation. Weather can change from hour to hour, day to day, and season to season.

Vocabulary

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Materials. . . . . . . . . . . . . . . . . . . . . • Drawings of simulated tree rings, which are included in this lesson or accessible at the

following locations: Jackson, Mississippi: https://mynasadata.larc.nasa.gov/docs/Jackson_Tree_Ring.pdf

Columbia, Missouri: https://mynasadata.larc.nasa.gov/docs/Columbia_Tree_Ring.pdf

Boston, Massachusetts: https://mynasadata.larc.nasa.gov/docs/Boston_Tree_Ring.pdf

Seattle, Washington: https://mynasadata.larc.nasa.gov/docs/Seattle_Tree_Ring.pdf

• A copy of Tree Ring Analysis Worksheet, one for each student • Computer(s) with internet access • Tree Ring Data Sets (for use in place of online)

Procedure Preparation . . . . . . . . . . . . . . . . . . . . . Students should prepare for the lab by brainstorming methods scientists could use to study climate. Have drawings of simulated tree rings copied (and laminated for future use) as well as Tree Ring Analysis worksheet. Students will need to access the NASA database online, so they will need at least one computer per group. Each group will need a team copy of the tree rings drawings (provided). Investigation . . . . . . . . . . . . . . . . . . . . Part 1: Discussion: Climate Clues

1. Remind students about the differences between weather and climate. [Answer: Weather is a specific event or condition that happens over a period of hours or days. For example, a thunderstorm, a snowstorm, and today's temperature all describe the weather. Climate refers to the average weather conditions in a place over many years (usually at least 30 years). For example, the climate in Minneapolis is cold and snowy in the winter, while Miami's climate is hot and humid.]

2. Instruct students to go to the “Think Like a Scientist” page on EPA’s A Student’s Guide to

Global Climate Change website (http://www.epa.gov/climatechange/students/scientists/index.html). Ask them to explore how scientists gather information about the Earth’s current weather and past climate by selecting “learn more” in “A Scientist’s Toolbox” section on the right side of the screen.

3. Ask students why gathering information about past climate is important.

[Answer: Knowing what the planet’s climate was like in the past—and the kinds of changes that have occurred in the Earth’s climate over time—can help us determine whether changes that are occurring now are part of the Earth’s natural pattern or caused by human activities. We can also look at these patterns to help us anticipate future changes that could occur.]

4. Discuss tree rings and how they provide information about weather and climate, using an

example for illustration. • You can use one of the drawings from the end of this lesson plan, or you can use an

actual tree stump if you have a good example available nearby. Explain that the light-colored rings are the wood that grew in spring and early summer, while the dark rings indicate growth in late summer and fall. Thus, a light ring and dark ring together represent one year of growth. Tree ring records can go back hundreds to thousands of years, depending on when the tree lived and how old it was. Because tree rings are sensitive to local climate conditions such as precipitation and temperature, they give scientists some information about an area’s past local climate or “micro-climate.” For example, rings generally grow wider in warm, wet years and thinner in cold, dry years.

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When faced with extremely stressful or unfavorable conditions, a tree might hardly grow at all.

Part 2: Analyzing Tree Rings

1. Explain to students that they will be examining two sets of data to learn about

precipitation patterns during a given time period: 1) tree rings and 2) data from NASA.

2. Hand out the simulated tree ring drawings. Pass out a “Tree Ring Analysis” worksheet to each student.

3. Have students observe the rings in each tree ring slice and examine the width of the rings.

4. Remind students that the width of the rings indicates the quality of the growing conditions

during that season. If all tree rings have consistent thickness, it is possible that the local conditions were also consistent through the life span of the tree. Narrower rings might indicate stressful conditions. Ask students to if they can think of a stressful condition that affects plant growth. [Most obvious answer: Drought. In the United States, droughts have caused massive food shortages and costs billions in crop damage in recent years.]

5. Have each student (or group of students) choose one of the four tree ring samples and fill out Part I of the “Tree Ring Analysis Worksheet” for that tree. Have students determine the age of each tree. Have them being counting only the dark rings from the center of the tree, working toward one edge. The outermost green (dark) layer represents the late season wood from the most recent growing season, and the light layer just inside corresponds to the spring growth from that season. Count each dark ring only once. This corresponds to the number of years the tree was alive. To determine the year in which the tree was planted, subtract the number of dark rings (age of tree) from the year in which the tree was cut.

Part 3: Computer Activity: Comparing Tree Ring Data with Precipitation Data

1. Have the students access the MY NASA DATA website at: https://mynasadata.larc.nasa.gov/las/getUI.do.

2. If students are not automatically prompted with parameter choices, have them select

“Choose Dataset” in the upper left-hand corner of the screen. Then select “Atmosphere,” then “Precipitation,” and then “Monthly Precipitation (GPCP).”

3. From the menu on the left side of the screen, have students select “Time Series” from the

“LINE PLOTS” options. Then have them click on the box next to “Update Plot” found at the top of the screen above the navigation map.

4. Have students change their time range to suit their tree sample. Note that the records in the

database begin in 1979.

5. Have students use the “Zoom” button to zoom in on North America, or have them enter the

latitude and longitude for their selected location. To find their location, students can also

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adjust the position of the cursor until the coordinates match the area where the tree grew. Students can enter the coordinates directly in the compass box shown.

6. Have students fill out Part II of the “Tree Ring Analysis Worksheet.” For the calculation

portions of the exercise, have the students click “Save As.” A dialogue box will appear titled “Download Data.” Change the format to “ASCII” and click “OK.” A new window should appear with all the data. Students can compute the average daily precipitation for an entire year by adding the monthly data points and dividing by the number of points (i.e., 12).

7. As a class, discuss the results. Did the NASA data confirm your tree ring analysis? If not,

what might account for the differences between the two measurements? [Answer: Results will vary based on each tree ring cross-section. Differences between the two measurements could be due to other factors that influence the growth of the trees, such as temperature, sunlight, and wind. Additional factors could include local-scale “microclimate” conditions and disturbances such as competition from neighboring trees, run-off fertilizer from a nearby farm, or an insect outbreak that may affect the growth of the tree.]

8. Can you suggest where one might find data to examine other factors that could influence tree

growth? [Answer: One can also look at other climate factors that affect tree growth, such as temperature and wind. National or local weather stations can provide these data.]

Discussion Question. . . . . . . . . . . . . . . . . . . . . Tree ring patterns can help shed light on local climate conditions during the growing season. What are the challenges involved in trying to determine global climate from tree rings? Possible Answer: Not every biome on Earth has hardwood trees. The oceans obviously do not have trees, and neither do deserts, polar regions, or high mountains. Trees in the tropics grow year-round, so they do not have distinguishable rings. And temperate trees can’t tell us much about winter conditions. Still, if trees in many different parts of the world show similar patterns, it can a good indication of a global change.

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Jackson, Mississippi https://mynasadata.larc.nasa.gov/Jackson_Tree_Ring.pdf Approximate coordinates: 32˚N, 90˚W Average daily precipitation in Jackson, MS, 1979-2007: 3.7 mm/day

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Columbia, Missouri https://mynasadata.larc.nasa.gov/Columbia_Tree_Ring.pdf Approximate coordinates: 39˚N, 92˚W Average daily precipitation in Columbia, MO, 1979-2007: 3.0 mm/day

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Boston, Massachusetts https://mynasadata.larc.nasa.gov/Boston_Tree_Ring.pdf Approximate coordinates: 42˚N, 71˚W Average daily precipitation in Boston, MA, 1979-2007: 3.76 mm/day

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Seattle, Washington https://mynasadata.larc.nasa.gov/Seattle_Tree_Ring.pdf Approximate coordinates: 47˚N, 122˚W Average daily precipitation in Seattle, WA, 1979-2007: 3.5 mm/day

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Tree Ring Analysis Worksheet Part 1: Tree Ring Analysis 1) Tree ring location: _____________________________ 2) Number of dark rings: __________ 3) Year tree was planted: __________ Select one ring that seems to reflect below average precipitation for the growing season, based on its width. Determine the corresponding year by counting the rings, starting with the youngest ring, which is closest to the bark. List the year you have selected: _____________ Part 2: Computer Analysis 1) Navigate to the MY NASA DATA website: https://mynasadata.larc.nasa.gov/las/getUI.do

• In the upper left corner, you will see a gray rectangle marked ‘Data Set’. Click on it. • Then select ‘atmosphere’ by clicking on the small box with a plus sign to the left of

‘atmosphere’. • Next, click on the small box to the left of ‘precipitation’ to select it. • Then click on the small box to the left of ‘Monthly Precipitation (GPCP)’ to select it.

2) From the menu on the left side of the screen, select ‘Time’ from the Line Plot options. In the upper left corner, click on the small box to the right of the gray rectangle marked ‘Update Plot’. 3) On the central left part of the screen, change the start date and end date to suit your tree ring

sample. Note that the records in the database begin in 1979.

4) In the small map on the left part of the screen, select the city from which your tree ring was obtained. Click on the tiny magnifying glasses above the map to zoom in or out.

What is the latitude of your tree’s city? _______________________ What is the longitude of your tree’s city? _______________________ 5) At the top of the page in the center, click on the button marked ‘Save As’. A new screen will appear with your selected region and time. Under ‘Select a Data Format’, scroll down and select ‘ASCII’, then click on the save button. 6) A new screen will appear with your data. Calculate the average daily precipitation for the

entire year but adding the monthly data points and dividing by the number of months (12). What was the average monthly precipitation for the year you selected?

Year: _____________ Precipitation: __________________

7) Compare your result with the average precipitation rates listed under your tree ring picture. Was the year you selected drier than normal? Explain.

8) What other factors might influence tree growth, besides total precipitation? Which factors do you think are most important? Where could you find data to confirm this?

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Tree Ring Analysis Worksheet –ANSWER KEY Part 1: Tree Ring Analysis 1) Tree ring location: BOSTON, MA 2) Number of dark rings: 19 3) Year tree was planted: 1981 Select one ring that seems to reflect below average precipitation for the growing season, based on its width. Determine the corresponding year by counting the rings, starting with the youngest ring, which is closest to the bark. List the year you have selected: 1994 Part 2: Computer Analysis 1) Navigate to the MY NASA DATA website: https://mynasadata.larc.nasa.gov/las/getUI.do

• In the upper left corner, you will see a gray rectangle marked ‘Data Set’. Click on it. • Then select ‘atmosphere’ by clicking on the small box with a plus sign to the left of

‘atmosphere’. • Next, click on the small box to the left of ‘precipitation’ to select it. • Then click on the small box to the left of ‘Monthly Precipitation (GPCP)’ to select it.

2) From the menu on the left side of the screen, select ‘Time’ from the Line Plot options. In the upper left corner, click on the small box to the right of the gray rectangle marked ‘Update Plot’. 3) On the central left part of the screen, change the start date and end date to suit your tree ring

sample. Note that the records in the database begin in 1979.

4) In the small map on the left part of the screen, select the city from which your tree ring was obtained. Click on the tiny magnifying glasses above the map to zoom in or out.

What is the latitude of your tree’s city? 42.3601˚N What is the longitude of your tree’s city? 71.0589 ˚W 5) At the top of the page in the center, click on the button marked ‘Save As’. A new screen will appear with your selected region and time. Under ‘Select a Data Format’, scroll down and select ‘ASCII’, then click on the save button. 6) A new screen will appear with your data. Calculate the average daily precipitation for the

entire year but adding the monthly data points and dividing by the number of months (12).

What was the average monthly precipitation for the year you selected? Year: 1994 Precipitation: 3.7o mm/day 7) Compare your result with the average precipitation rates listed under your tree ring picture. Was the year you selected drier than normal? Explain. YES (Explanations may vary) 8) What other factors might influence tree growth, besides total precipitation? Which factors do

you think are most important? Where could you find data to confirm this?

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[Answer: Other environmental factors such as temperature and access to sunlight can influence tree growth, and thus affect ring width. Stress from fire, insects, or disease could reduce growth in certain years. To examine these other factors, we can get temperature and wind data from the national or local weather bureaus, and we can get land use and forest health information from state or national forestry organizations. We can gather additional data by sampling more than one tree per site. Looking at the previous year is helpful because severe drought conditions can persist over many months, and a relative lack of precipitation in one year can reduce the amount of moisture in the soil in subsequent months or years.]

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ACTIVTY 5: Ice Cores: Exploring the History of Climate Change This activity has been adapted from teacher Tracey Leider of Oregon High School, The Habitable Planet, and Ice Core Investigations by Antarctic Climate & Ecosystems CRC. This activity models the use of climate data to determine cause and effect relationships between geochemical cycles and atmospheric composition. Students will analyze fabricated ice cores and record their physical and chemical characteristics. Go to: http://www.pbs.org/wgbh/nova/warnings/stories/icecore.html for sample data Students will: • Understand climate is a fluctuating system • Demonstrate how scientists estimate historical climate data using ice cores • Predict outcomes of a scientific investigation and then conduct the investigation • Analyze the results of their scientific investigation Background Throughout much of its 4.5 billion year history, Earth’s climate has been in a state of fluctuation. Some eras were dominated by coldness while others were characterized by warmth. Some of these periods included drastic fluctuations while others remained fairly stable for millions of years. Four major continental glaciations are recorded in North America. The last (Wisconsin) began about 70,000 years ago and ended 10,000 years ago. Much of Wisconsin’s geological landscape was influenced by glaciation. The northern half of the state is mixed hardwood and coniferous forests. Farmland and prairies exist primarily in the southern half where the glaciers dropped sediment that made the land nutrient rich. The bluffs and narrow valleys of the Driftless Area, in the south - western corner of the state, are places where the last glaciers did not reach and, thus, the landscape was not scraped or leveled. The polar regions of the world have held ice throughout and between these glacial periods. Like rings of trees in temperate parts of the world, ice layers in polar regions and glaciers also create layered historical records. Layers of snow become compacted into ice, which are laid atop previous layers of ice to create these records of the past. To analyze historical climate changes, scientists drill down into the ancient ice where information about the atmosphere has been captured. Scientists extract the ice core and use it to analyze atmospheric physical and chemical characteristics to create scientific snapshots of Earth during single points in time (Fig. 1). Small bubbles in the ice hold trapped atmospheric gases from hundreds of thousands of years ago. When scientists analyze the composition of those trapped gases they are measuring the concentrations of gases in Earth’s atmosphere when each layer was formed, including the concentration of carbon dioxide (CO2), a greenhouse gas. In addition, the water in each layer of the ice holds oxygen and hydrogen isotopes. The relative concentrations of these isotopes will vary depending on the temperature when the layer was created. Thus, the scientists are able to determine the historical record of the temperature as well. Perhaps the most famous study of this type is the Vostok ice cores from Antarctica. These data are often cited in climate change articles. By showing a correlation between global temperatures and atmospheric CO2 levels, scientists find evidence that changing the concentration of CO2 in the atmosphere can change the global temperature and climate.

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In this activity, students will not be able to measure directly the CO2 of trapped atmospheric gases or the relative oxygen and hydrogen isotopes of the water. However, they can analyze other physical parameters to get a sense for how scientists learn about the past from ice cores and also the studies done related to climate change.

Fig. 1 Age of Ice Core Layers

Materials Kit Provides: ● Plastic graduated cylinders (50 ml)- one

per group ● Food coloring – various colors ● Carbonated sparkling water ● Acid (vinegar or lemon juice drops) ● pH paper ● Rulers ● Miter box with saw ● Trays ● Disposable cups ● Coffee filters

Teacher Provides: ● Student worksheet copies ● Particles (ashes, cat litter, or other

dusty material) ● Freezer with enough space to store

cylinders upright ● Electronic balance Optional: ● Vernier LabQuest ● CO2 Probe ● pH meter

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Procedure Preparation . . . . . . . . . . . . . . . . . . . . . 1) Home Assignment: Students should prepare for the lab part of this activity by learning how scientists analyze ice cores for information on changes in Earth’s atmosphere over time. This preparatory work will give students a broader understanding of how this research is conducted and the opportunity to analyze evidence of the link between atmospheric CO2 and global temperatures. 2) Instructor notes for making ice cores (Note: Allow up to 5 days for preparation of this activity before you present it to students)

● Several days before class, make an ice core for each group of 2-3 lab partners. Use the PVC tubes and end caps provided in the PARC kit. You may also use 50 ml graduated cylinders or other long narrow containers to make the ice cores: they should be able to stand upright in the freezer. You will make the cores with at least 3 different layers. After mixing up and adding each layer to each ice core, you will need to freeze the ice core completely before adding the next layer, so plan several days of preparation time.

● Plan to give each layer a unique color (to help students separate the layers), volume (to simulate varying levels of precipitation), dissolved solids (to simulate both pollution and ash from volcanic eruptions), dissolved CO2, and pH.

● Mix up a solution for the first layer. Add a small amount of solids (ashes, ground up cat litter, or other dry or dusty substance) to tap water and some food coloring for dye to this first layer. Record the amount of sediment you added and measure and record the pH of the solution. Stir the solution to suspend the solids and pour the same amount of the solution into each cylinder. Freeze overnight or until solid.

● Mix up the next solution, this time adding carbonated sparkling water to the tap water (perhaps 10% sparkling water and 90% tap), a different amount of solids, and a different color of dye. (Note: the solids could represent pollution or volcanic action, so you may want more solids in the topmost layers to represent pollution from industrialization as well as solids in an earlier layer to represent a geologic time with much volcanic activity.) Again, measure the pH and record the composition of this layer. (If the pH is not different from the first layer, try adding more sparkling water or some vinegar to reduce the pH.) Add this solution on top of each of the frozen cylinders. Refreeze overnight.

● Continue making additional layers, varying the parameters and freezing between each addition. To simulate increased CO2 in the atmosphere, have the last layer be a solution of 50% carbonated sparkling water and 50% tap water. You could also add more solids to this layer to simulate increased pollution from industrialization.

● The Instructor will bring the ice core samples to class (packing them in ice and dishtowels in a cooler helps protect them until class time) and distribute one ice core per 2-3 students.

Investigation . . . . . . . . . . . . . . . . . . . . 1) The class will investigate the chemical and physical characteristics of each layer. 2) Begin with a class discussion of ice core analysis and how ice core data is used. Refer to the research or readings assigned to this lab. Inquiry-based questions:

● What do scientists measure when they are studying ice cores? ● What types of atmospheric data might be useful if we’re looking for evidence of climate

change? What can be measured? ● How might scientists correlate a given layer of ice with a given time period? How would they

know the age of each layer?

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3) Students should: ● Separate layers

– The instructor will identify which colored layer represents the top, or most recent, layer of the ice sheet they are analyzing. – Remove the cores from the cylinder by pouring warm water over the cylinder or by setting it briefly in a warm water bath. At this point, only melt enough of the outer part of the core to remove it from the cylinder. –Gently break each ice core layer apart. Using the small saw and miter box provided will assist in keeping the layers cleanly separated. If the layers are still firmly frozen, allow for more time to thaw before attempting to saw them apart.

● Compare precipitation in each layer –Measure the mass of each layer and record the results on the Ice Core Data Table on the student assignment page.

Research Worksheet. . . . . . . . . . . . . . . . . . . . . . –Measure the volume of each layer and record the results. – Optional: Density can be calculated once the mass and volume are known.

● Compare pH and CO2. CO2 in solution with water becomes carbonic acid, dropping the pH, so measuring relative pH should indicate relative levels of CO2. – Before measuring for pH, predict which layers will have the highest and lowest pH and record their predictions. –Melt the ice and collect the resulting solution for each layer. –Measure the pH of the layer by using a pH meter or pH paper.

● Measure particulates – Before measuring for the suspended solids or particulates, hypothesize the relative amounts of particulates in each layer and record their predictions. Do students guess that the more recent layers will have more particles and pollution because of the industrial revolution? –Measure and record how many ml of each layer they will test for particulates. Evaporate this amount of each layer in a pre-weighted container. Reweigh the container to get a weight for the remaining solids. –Alternatively, weigh filters for each layer, recording the weight. Then filter the liquid in each layer, dry the filters, and reweigh the filters to calculate the weight of particulates. – Record results as grams of particulates per milliliter of liquid. Convert this to grams of particulates per liter.

Discussion Questions. . . . . . . . . . . . . . . . . . . . . On the board or other visual display, students will report their results. Construct a class data table for recording volume, weight, density, pH, and particulates and have the students’ class data displayed.

● Determine sources of error for the overall experiment and per group. Were there better, more accurate ways to conduct the ice core experiment? How could the investigation have been done differently to improve results?

● What conclusions can you draw? Which layers represent wet or dry years? How do you know? Were some layers more acidic than others? Why and what is the relation to climate change? Did the level of particulates vary? What might be the sources of these particulates in the atmosphere?

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Ice Core Research Student Assignment NAME _______________________________________________

TEAM MEMBERS _______________________________________

DATE ________________________________

Ice Core Sample ID # ______________

1) From your reading and research, how do scientists learn about Earth’s past from ice sheets and glaciers? What kinds of information do they gather? 2) How do scientists estimate temperature and carbon dioxide levels from thousands of years ago, using their ice core analyses? 3) How do scientists estimate the age of a given layer in an ice core? 4) Measure the depth of each layer in centimeters and draw a diagram of your ice core in the space below. 5) Based on prior knowledge and reading, predict which layers will have the highest and lowest pH and the highest and lowest particulate contents. What is the rationale behind your predictions? 6) Separate each layer from others by gently cutting or breaking them apart.

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7) Measure the mass of each layer on the balance to the nearest tenth of a gram. Record your results in the data table. 8) Measure the volume of each sample using the method provided by your instructor. (Record the results in the data table.) Calculate the density. 9) After predicting the relative pH for the various layers, measure and record the pH of the sample, using the method provided by your teacher. How does the measured pH compare with your predictions? Do the results surprise you? Why or why not? 10) After predicting the pollution levels, weigh and record the amount of particulates or solids in each sample using the method provided by your teacher. Were your predictions accurate? If not, what might be a reason for the discrepancy? What can cause particles and soot in the air? ICE CORE DATA for Sample # _______________________

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Lab Extension: Qualitative and Quantitative Ice Core Lab Analysis Description of the activity/assignment Students access the ice core data archived at Lamont-Doherty Geological Observatory. They select a core (Greenland, Antarctica, Quelcaya), pose a working hypothesis regarding the data, import the data in an Excel-readable format, and examine the data to determine correlations between variables and cause/effect as recorded in leads and lags. They generate a written and graphical analysis of the data and, in the next lab period, discuss the similarities and differences among their group outputs in terms of demonstrated correlations, assumptions required, effects of latitude, and any other item that arises.

Ice Core Exercise Ice cores are one of the best terrestrial repositories of environmental data, including as much as 400,000 years of interpretable paleoenvironmental information. Some of this information is available to you in a near-raw format! Investigate some of these data. The data are archived at and downloadable from http://ingrid.ldgo.columbia.edu/SOURCES/.ICE/.CORE/ .

Investigate relationships between any two variables accessible from that source. Note that Quelccaya is a short core with little to compare to the longer records. The GRIP core spans from 8 ky to 40 ky BP and includes methane and oxygen isotope data. The Vostok data spans the last 160,000 years and lists 8 values (including inferred temperature difference from present). So - what interests you? The similarity between Greenland and Antarctic oxygen isotope compositions? Whether methane or CO2 is a better predictor of climate? Whether climate lags CO2 or vice-versa? Please investigate one such issue, following the methodology below:

● Write your question (perhaps in the form of a testable hypothesis!) ● Download the data you need to answer your question. The preferred format is .tsv, which is

readily importable into Excel. ● Import your data. If it doesn't parse into separate columns automatically, use Excel's

Data...Text to Columns... capability, or equivalent, to generate one or more columns of data for each variable.

● Transform your data to a common scale. That scale could be depth or age in a single core, but must be age between cores. In order to compare data sets, you must have an array of numbers, with no gaps, in the form Z, var1, var2, where Z is depth or age and var1 and var2 are your variables of interest. [This is the hard part of this exercise.]

● Correlate your data. Use the statistical analytical tools available to you (e.g., Excel's Tools...Data Analysis..., Correlation) to answer your question. To test the presence of a lag or lead simply shift one variable column up or down a row at a time, calculating correlation, to see if the correlation improves or worsens. Do so enough steps to demonstrate worsening to insignificance.

o Potential problem: if the Data Analysis package has not yet been invoked on your copy of Excel, it may not show up in the Tools menu. Use Excel Help to find the instructions to Install the Analysis Toolpak - an add-in that should be lying dormant within the software.

● Submit a short (<2 page) write-up describing your question, your approach, your outcome, and the statistics that support it.

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Going Beyond. . . . . . . . . . . . . . . . . . . . . 1) Research the methods used by scientists to figure out dates of ice core samples. Why would this be important for climate change research? 2) Add other parameters to the ice cores for the students to measure. For example, to simulate heavy metals in the atmosphere from pollution, you can add about 1% by volume of 0.1M copper chloride solution to a layer. Students can analyze layers for the presence of copper by adding a small amount of dilute sodium hydroxide to a portion of the melted layer and observing the result over a white background. The presence of copper will turn the resulting solution a faint blue. To detect a difference in color, students should compare the portion they treated with sodium hydroxide to the untreated portion.

**Note that chemicals mentioned above are not provided in the PARC kit.

Supporting references/URLs The data are archived at the International Research Institute for Climate and Society - http://ingrid.ldgo.columbia.edu/SOURCES/.ICE/.CORE/. Note that many other data sets are also accessible through the Archive home page - http://iridl.ldeo.columbia.edu/. All required materials are available at The Lamont-Doherty Earth Observatory link Vostok Ice core data lab – http://serc.carleton.edu/resources/14159.html

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