1. Lab Safety Rules/Activity Science Introduction and Expectations
Monday, August 25, 2013
Tuesday, August 26, 2013
Monday, August 25, 2013
Tuesday, August 26, 2013
Lab Safety Rules/Activity
Science Introduction and Expectations
Warm Up:
Welcome to 8th Grade Science. Record your answers on clean paper. Prepare to share.
Who was your science teacher last year?
What was your favorite science unit last year? Why?
Name one thing you hope will happen this year in science.
Name one thing you hope won’t happen this year in science.
Homework:
1. Prospectus goals and signatures
2. Safety contract – signatures
Teacher wiki – home page summary and facts about me

3. 8th Grade Science Interactive Notebook Set-up

4. Page Set-Up Expectations
Date A-Day Date B-Day
Date A-Day Date B-Day
Classwork Titles
Notes
Diagrams
Activities
Handouts
Topic Title
Essential Question:
Write out questions
Answer to Essential Question: Complete sentences
Warm Up:
Answer question in complete sentences
Homework: Homework assignments should always be written in your planner!
Page #
Page #

5. Inside Cover of Notebook
Date A-Day Date B-Day
Homework Title(s)
Warm Up:
Write out questions, charts, diagrams AND your responses!!!
Inside Cover of Notebook
Keep This Page Blank!!!!
Homework: Homework assignments should always be written here, as the title AND in your agenda!
Page #

6. Technology Cheat Sheet
Prospectus Page
Tape Technology Cheat Sheet
Here
Tape 8th Grade Science Prospectus Here

7. Science Introduction and Expectations
Wednesday, August 27, 2014
Thursday, August 28, 2014
Wednesday, August 27, 2014
Thursday, August 28, 2014
Discovery Ed. Webquest
Science Introduction and Expectations
Fill in Technology Cheat Sheet and attach to your notebook
1. Gaggle / Chromebook login
Username:
(first initial + last name + last 4 of student id)
Password: YYMMDD
2. Discovery Education Science TechBook
User ID/Login: (student ID#_cms)
Password: (student ID #)
3. Powerschool
Username: (middle set of numbers)
Password: (last set of numbers)
Essential Question: Using DE, what resources are available to explore the rock cycle? How are these resources useful?
Warm Up:
Using the following 10 words, sort the words into two categories. Create a t-chart and label each column.
Lithosphere
Genetics
Natural selection
Mantle
Cells
Sedimentary Rock
Rock layers
Organs
Plate tectonics
DNA
Homework: Using DE “Fossils and Studying
Earth’s Past” choose one video, and summarize. Write the main idea, 3 supporting details in your paragraph.
Page 2
Page 1

8. SchoolNet Test ID FA2CY3QE 30 Question pre-assessment
Read the question
Select an answer for all questions
Click the “Next” button
When you finish, Log into Discovery Education
Earth’s History = 1st Unit

9. Discovery Education
Interactive vocabulary - choose 3 words and write a summary (1 video, 1 animation, and 1 definition) rock cycle, sedimentary rock, superposition, igneous, convection, asthenosphere
Essential Questions - Locate 2 questions in the orange question tab- copy and answer: 1 question you definitely know the answer, copy question you have no idea the answer
Homework - Chose one video, and write summary. Write main idea, 3 supporting details paragraph

10. Earth and the Rock Cycle
Friday Aug 29, 2014
Tuesday, Sept 2, 2014
Friday Aug 29, 2014
Tuesday, Sept 2, 2014
Earth’s History Unit
Earth and the Rock Cycle
Outline of Unit
Earth’s Structure and Rock Cycle
Relative and Absolute Dating
Fossil Evidence of Earth’s Age
Geologic Time Scale
Evolution and Genetic Variation
Natural Selection

11. Earth’s Structure and Rock Cycle
Friday Aug 29, 2014
Tuesday, Sept 2, 2014
Friday Aug 29, 2014
Tuesday, Sept 2, 2014
Earth’s Structure
Earth’s Structure and Rock Cycle
Earth’s Layers
Essential Question: Explain the different types of rocks found on Earth’s surface and some physical results of geologic change on the Earth’s surface? Give examples.
Rock Cycle
Warm Up: Using textbook p Answer the following questions in complete sentences:
Explain how Earth is made up of materials with different densities.
How can scientists explore the Earth’s interior without seeing it?
Igneous Rock
Sedimentary Rock
Homework: Answer the essential questions on pages 1 of your notebook.
Metamorphic Rock
Page 3
Page 4 11

12. Characteristics- clear description, diagrams, labeled, color
Rock Group Jigsaw Instruction Sheet Rubric
Goal: Present the required information in approximately 4 minutes.
READ ALL RESOURCES. TAKE NOTES AND DETERMINE THE IMPORTANT DETAILS TO TEACH TO THE CLASS
Characteristics- clear description, diagrams, labeled, color
Change over time - how it changes (rock or structure of the Earth)
Supporting Details - fossils, crystals, remains of organisms, energy (radioactivity from Earth’s core)
Key Vocabulary (suggested to use): cementation, minerals, crystallization, fossils, heat, pressure, melting, temperature, core, crust, mantle, asthenosphere, layer, erosion, sediment, change over time, deposition, lava, magma, tectonic plate

13. ======================== Theory of Uniformitarianism (3:20) &
Wednesday, September 3, 2014
Thursday, September 4, 2014
Wednesday, September 3, 2014
Thursday, September 4, 2014
Earth Structure
Earth Structure and Changes
Essential Question: What is earth’s structure and some physical results of geologic change on the Earth’s surface? Give examples.
Notes from group presentations
Layers of Earth
Rock Cycle
Igneous
Metamorphic
Sedimentary
========================
Theory of Uniformitarianism (3:20)
&
Five Ways Earth Changes (11:00)
DE Video Clips Notes
Warm Up:
The stem GEO- means Earth. Make a list of as many words that you can think of that involve the stem GEO-.
Homework:
1. Bring in at least one picture representing at least one geologic change. I.D. when, where, how (Weathering, Erosion, land mass motion, volcanic eruption, Earth crust movement)
2. Answer the essential question from page 3 of your NB
Page 6
Page 5 13

14. Think-pair-share What do you think you’re looking at
Think-pair-share What do you think you’re looking at? What kind of rock is in the picture? What happened that may have caused this to happen?

15. Check for understanding
How is the structure of the earth similar to a boiled egg?
How are rocks recycled over time? Discuss three rock types.
How does the earth change over time?

16. Essential Questions (leave space to answer):
Friday, September 5, 2014
Monday, September 8, 2014
Friday, September 5, 2014
Monday, September 8, 2014
Forces that Build and Destroy
Mining Earth’s Changes
Evidences for the Theory of Uniformitarianism
Essential Questions (leave space to answer):
How does the sun affect the formation of sedimentary rocks?
How do magma and lava differ?
How does the formation of intrusive and extrusive rocks differ?
How does increasing pressure and temperature affect a rock?
What?
When?
Where?
How did it happen?
Crustal Movement
Volcanic Eruption
Weathering
Erosion
Land Mass Motion
Warm Up:
How does the Theory of Uniformitarianism help us understand earth’s history? (Use your video notes from last class.)
What evidence do scientists use to study earth’s history?
Homework: Answer all essential questions.
Page 8
Page 7 16

17. Constructive And Destructive Forces Web-quest Resources
Task: Evaluate online resources and create an informational brochure
Use the organizer provided by teacher
Maximum group size = 3
Use selected resources
Carefully complete each section
Self assess your use of essential vocabulary and your level of understanding.

18. Essential Questions (leave space to answer):
Tuesday, September 9, 2014
Wednesday, September 10, 2014
Tuesday, September 9, 2014
Wednesday, September 10, 2014
Classify
Rock Classification Lab
Problem: What properties can be used to classify rocks?
Data:
Essential Questions (leave space to answer):
What properties can be analyzed to classify rocks?
Sample Number
Visible Properties
Rock Type 1 2 3 4 6 8 9 11 14 15
Warm Up:
Why are the names intrusive and extrusive appropriate for two types of igneous rock?
What is their main difference?
Homework:
Make sure all E.Q.s have been answered.
Test Mon (A) and Tues(B)
Earth’s Layers,
Rock Cycle,
3 Types of Rock
Uniformitarianism
Forces of Change
Answer analysis questions 1-2 and 1-3 completely.
Page 9
Page 10 18

19. Essential Questions (leave space to answer):
Thursday, September 11, 2014
Friday, September 12, 2014
Thursday, September 11, 2014
Friday, September 12, 2014
Complete Labs (1st ½ of class)
Test Review (2nd ½ of class)
Essential Questions (leave space to answer):
How are rocks distributed in earth’s crust?
1. Complete “Rock Activities 2 and
Attach your work to page 10
2. Review sheet
Warm Up:
1. How is the structure of the earth similar to a boiled egg?
How does the earth change over time?
How are rocks recycled over time?
What role does the sun play in rock formation?
Homework:
Make sure all E.Q.s have been answered.
Test Mon (A) and Tues(B)
Earth’s Layers,
Rock Cycle,
3 Types of Rock
Uniformitarianism
Forces of Change
Page 11
Page 12 19

20. Rocks Activities 2 and 3 2. A Crust Full of Rocks 3. Mystery Rocks
Study the graphs
Answer 1-7 in complete sentences
Problem: What properties can be used to classify rocks?
Data:
Analyze and Conclude Questions 1-6
Sample
Color
Texture
Foliated or Banded
Rock Group
A= 1
B=4
C=6
D=11
E=14
F=15

21. Essential Questions (leave space to answer):
Monday, September 15, 2014
Tuesday, September 16, 2014
Monday, September 15, 2014
Tuesday, September 16, 2014
Law of Superposition and Relative Age of Rocks
Rock Cycle and Uniformitarianism Test
Essential Questions (leave space to answer):
How are rocks used to construct earth’s chronological history?
Relative Age – the age of an object in relation to another object
If undisturbed, oldest on the bottom and youngest on the top
Law of Superposition - layers (strata) that are younger will be deposited on top of layers that are older
View
DE Interactive
“Superposition”
Warm Up:
Think about the word “recrystallization”.
What do you think happens during this process?
What type of rock does the word allude to?
Homework:
1. “ Determining Which is Older” handout
color code rocks and identify which is older
2. Answer today’s E.Q.
Page 13
Page 14 21

22. Forces that Disturb Chronologycontinued
Movement of Tectonic plates
Can bend layers like a taco (oldest layer may be bent until its on the top.
Faults – a break in earth’s crust where rock slips past another
Intrusion – magma (igneous rock forms) that has forced its way through existing rock layers

23. Sometimes Rock History Erodes Away
Unconformity - a buried erosion surface separating two rock masses or strata of different ages (a missing rock layer due to erosion)

24. Bending – from plate movement
Intrusion of magma that formed igneous rock
Fault – a plate moved and cracked and shifted existing rocl
Bending – from plate movement

25. Homework

26. Essential Questions (leave space to answer):
Wednesday, September 17, 2014
Thursday, September 18, 2014
Wednesday, September 17, 2014
Thursday, September 18, 2014
Exploring Geologic Changes
Exploring Geologic Changes
Essential Questions (leave space to answer):
1. How are rocks used to construct earth’s chronological history?
2. How do geologic changes impact earth’s geologic chronology?
Check for Understanding – “Forming and Unconformity”
==========================
Activity – “Exploring Geologic Changes in Rock Layers” (25 min)
Group roles – chief investigator, materials manager, timekeeper, problem solver
Materials foam blocks, 2 cardboard blocks, one textbook
Answer summary questions on clean paper
Warm Up:
Using the reading sheet Earth’s Crust in Motion:
Write main vocabulary words and definitions in your notebook
Copy main ideas
Think about:
How do stress forces affect rock?
Why do faults form and where do they occur?
How does movement along faults change Earth’s surface?
Homework:
Create your own diagrams. Draw, label, and color and example of a rock formation
Include the following: strata, intrusion, fault, unconformity, relative age from oldest to youngest
Page 15
Page 16 26

28. Answer Garden
You’re class’ access code is _______________. Question: What are the key words from the last two lessons? Watch your answers grow!!!!

29. Essential Questions (leave space to answer):
Friday, September 19, 2014
Monday, September 22, 2014
Friday, September 19, 2014
Monday, September 22, 2014
Absolute Age / Radioactive Dating
Absolute Age / Radioactive Dating
Essential Questions (leave space to answer):
Essential Questions:
How can the amount of parent material in a rock sample be determined by using half-lives?
How does the amount of parent material in a sample change as time increases?
3 minute “Check Up”
When studying an undisturbed rock core, how do you know which is the oldest and youngest rock layer?
When might the youngest layer in sedimentary rock not be on the top?
Can you determine the exact age of rock by studying layer positions?
Write your own definition for relative age.
Warm Up:
worksheet - “Relative Ages of Rocks”
Homework:
Bring in plain M&M’s or Skittles for a “sweet” lab!
Test Autopsy.
Page 17
Page 18 29

30. Information and examples
DE KIM Cards
radioactive dating
absolute age
Radioactivity
index fossils
half-life
Use DE for definitions and animations of the words red. Use your technology to research the words in black
Vocabulary Word
Definition
Information and examples
Picture/ Memory Cue

31. Determining Absolute Age…
Tuesday, September 23, 2014
Wednesday, September 24, 2014
Tuesday, September 23, 2014
Wednesday, September 24, 2014
Absolute Age / Radioactive Dating
Determining Absolute Age
Essential Questions (leave space to answer):
1. How do rocks provide evidence of earth’s absolute age?
Absolute Age –assigns a quantitative estimate of the number of years ago an event occurred.
Determining Absolute Age…
Radioactive Dating – using radioactive particles found in a rock to determine the actual age of the rock
Radioactivity – Radioactivity is a process in which subatomic particles escape from the nuclei of unstable atoms releasing energy.
See diagram atom
Warm Up
What is radioactive dating?
How is that different from relative dating?
Homework:
Bring in plain M&M’s or Skittles for a “sweet” lab!
Choose an element from the half- life chart and create a graph representing the daughter and parent element over time.
Test – October 1 and 2
Page 19
Page 20 31

32. Which rocks do geologist use?
-Igneous rocks are most useful due to unique chemical makeup. Radioactive materials are unchanged.
Sedimentary rock is not as reliable because it’s made of many different rock particles
Metamorphic dating usually results in the age of the change, not the original rock

34. Determining Absolute Age
Use an element’s Half-life: The time it takes for an element to decay.
Examples:
Carbon-14 has a half-life of 5,730 years.
Always found in LIVING organisms
Potassium-40 has a half-life of 1.3 billion years
Half Life You Tube
Using a specific calculation can help you determine the absolute age using half-lives

35. Visuals Help with Radioactive Decay See page 57A in textbook.
Original Rock
1 Half Life
2 Half Lives
3 Half Lives
4 Half Lives

36. Practice Time!!! Copy this chart
Element Y is found in an igneous rock and we are trying to determine the rocks age.
We know Y’s half life is approximately 3,000 years and that the rock is currently 6.25% radioactive.
How old is the rock?
Element Z is found in an igneous rock and we are trying to determine the rocks age.
We know Z’s half life is approximately 3,000 years and that the rock is currently 25% radioactive.
How old is the rock?
Element X is found in an igneous rock and we are trying to determine the rocks age.
We know X’s half life is approximately 3,000 years and that the rock is currently 50% radioactive.
How old is the rock?
Practice Time!!! Copy this chart
Percentage of Radioactive Material in Rock
Number of Half Lives
100%
50% 1
25% 2
12.5 % 3
6.25% 4
3.126% 5
100% Radioactive Igneous Rock
50% decayed
50%
Radio- active
87.5% decayed
94% decayed
75% decayed
25% r-a
12.5% 6%
One Half Life
Two Half Lives
Three Half Lives
Four Half Lives

37. Graph Examples

38. Graph Example

40. LAST PRACTICE ITEM FOR TODAY!!!
Closure - Venn Diagram Relative and Absolute Age

41. Essential Questions (leave space to answer):
Thursday, September 25, 2014
Friday, September 26, 2014
Thursday, September 25, 2014
Friday, September 26, 2014
M&M Lab and Article Review
M&M Lab and Article Review
Essential Questions (leave space to answer):
How can two sided objects be used as a model for radioactive decay?
Now it’s time for a sweet model !!
Two person TEAMS
1 – chief investigator and communicator
A = organized, sometimes organized, disorganized
B = Clear, almost clear, confusing
Materials Manager and Timekeeper
=========================================
Materials (per pair)
4 cups (2 original and 2 decayed)
25 candies (M&Ms or Skittles) EACH
2paper towel
25 minutes of time
USE THE RUBRIC when making the graph
Summary questions in your notebook.
Warm Up:
1. Grade your HW using the rubric
2. Pennies have two sides. Each time you flip a coin, what is the probability of getting heads or tails? ______
3. If given 10 coins, how could you demonstrate the half-life of elements? Propose an experiment using 2 sided coins. (________)
Homework:
Make sure all Essential Questions between pages 13 and 21 are answered thoroughly.
Relative and Absolute Age Test next Wed / Thurs
Page 21
Page 22 41

42. SchoolNet Quiz https://cms.powerschool.com/public __CY8WA7JE7_
10 Question open notebook quiz
Read questions carefully
Use a calculator if needed
Select an answer for all questions
After the quiz, go to Ms. Young’s wiki to access the enrichment activity.

43. Wrapping up
A - How did today’s activity model radioactive decay of material? B - Explain the similarities between the graph created today and the graph you created for homework. C - Argue that radioactive dating is more effective at determining the actual age of a rock than the Law of Superposition.

44. How did today’s activity model radioactive decay of material?
Check Out
How did today’s activity model radioactive decay of material?
Communicate to your partner one thing they did well and one area for improvement from the rubric.

45. Essential Questions (leave space to answer):
Monday, September 29, 2014
Tuesday, September 30, 2014
Monday, September 29, 2014
Tuesday, September 30, 2014
Test Review & Study Guide
Test Review & Study Guide
Essential Questions (leave space to answer):
Describe how rocks are used to study earth’s past.
Group A
Read 2 short radioactive dating articles and respond to text using text codes in your notebook (small handout)
View DE Video – “The Geology of the Grand Canyon” 4:06
Respond to text using text codes in your notebook (small handout)
Group B
Read 1 Relative Age article and respond to text using text codes in your notebook (small handout)
Warm Up:
Venn diagram comparing and contrasting relative and absolute age
Homework:
Study for your test. Test next class.
Study Notebook and activities between pages 17-24
Page 23
Page 24 45

46. 3-2-1 Article Summary Responses must be based on the article.
Lodge McCammon Songs: Radioactive Dating
Song in DE
Listen once 3:09
Complete guide second time
3 elements used for radioactive dating
2 objects commonly dated using radioactive dating
1 thing that helped you learn this concept the best

47. Rock Cycle, Relative and Absolute Age Test
Wednesday, October 1, 2014 Thursday, October 2, 2014
Wednesday, October 1, 2014 Thursday, October 2, 2014
Fossils
Rock Cycle, Relative and Absolute Age Test
Background
provide evidence that life on Earth has changed over time.
(Learning from Fossils clip 1:10)
(The Wooly Mammoth clip 4:25)
Fossils evidence indicate changes in Earth’s environment
Example -Tropical plant fossils found in polar regions indicate that polar regions were once much warmer than they are today.
Fossils Notes Organizer
Textbook – Section 2.1 A
Pages 45A – 51A
Article “Old Timers”
Use text codes to interact with the text
Essential Question:
How does the location of an index fossil help determine the age of rocks around it.
Warm Up:
Radioactive Dating Song
School Net Test ID
PE7KU8DA
Homework:
1. Finding Clues to Rock Layers handout
Page 26
Page 25

48. Fossils and Geologic Time Scale
Friday, October 3, 2014 Monday, October 6, 2014
Friday, October 3, 2014 Monday, October 6, 2014
Geologic Time Scale
Fossils and Geologic Time Scale
Essential Questions:
How does the geological scale help scientists learn about earth’s past life forms, land forms, and climate.
As geologists and paleontologists studied rock and fossil records, they found evidence of major changes in life and land forms at certain time.
Rocks records indicate that earth is about 4.6 billion years old
Evidence shows the moon formed around the same time so the moon is about____ years old.
Major changes relate or correlate to geologic time units
Geologic Time Scale is a timeline based on major events in the history of earth and/or life on earth
Warm Up:
You have gone through some major events as you have developed. When ….
a. Were you born? ______________
Start going to school? ________________
Large enough to sit in the front seat of a car?_____
Learn to tie your shoes? _______________
Homework:
Discovery Ed Video
“Historical Geology: A Glimpse of Earth’s Past” – 30 minutes
Page 28
Page 27

49. Literacy - Geologic Time Scale Article
Two ways to relate the order of geologic events…..:
Relatively: Placing events in a sequence
Chronologically: #s of years ago
===================================================================
DE Video – Discovery Ed Video
“Historical Geology: A Glimpse of Earth’s Past” – 30 minutes
You need a Interactivity Worksheet – your’s to write on
Read the instructions for the Interactivity Worksheet. Complete notes handout while viewing the program.

50. Change Over Time Brochure
Tuesday, October 7, 2014 Wednesday, October 8, 2014
Tuesday, October 7, 2014 Wednesday, October 8, 2014
Change Over Time Project
Change Over Time Project
Essential Question:
1. How do fossils show how organisms and environments have evolved over time?
2. How are fossil and geologic records used to show Earth’s history ?
Change Over Time Brochure
Use the template to organize the following topics: Research and describe the theory of continental drift and past continental, fossil evidence supports continental drift, organisms change over time.
Use the QR codes for selected research sites.
Creativity note: add image representative of the content
Make sure to use the rubric to self-assess your brochure
Warm Up:
Read the Geologic Time Scale reading sheet. Answer the following questions.
1. Why is the geologic time scale used to show Earth’s history?
2. What methods did geologists use when they first developed the geologic time scale?
3. How did geologists decide where one division of the geologic time scale ends and the next begins?
4. What are the different units of the geologic time scale?
Homework:
1. Finish the brochure
Page 30
Page 29

51. Go over fossil notes sheet
Thursday, October 9, 2014 Friday, October 10, 2014
Thursday, October 9, 2014 Friday, October 10, 2014
Geologic Time Scale Wrap Up
Geologic Time Scale Wrap Up
Essential Question:
1. How do fossils show how organisms and environments have evolved over time?
2. How are fossil and geologic records used to show Earth’s history ?
B day
Paleontology review
Go over fossil notes sheet
Summarize Patterns : ‘Historical Geology: A Glimpse of Earth’s past’
Are you ready for some Football!
Warm Up:
Using your fossil notes sheet and the Old timers article.
1. How do fossils provide evidence of environmental changes that occurred in the past?
2. An ancient tropical fossil was found in the polar region. What do you think a paleontologist would suggest based on this finding? Explain why.
3. List the 5 characteristics of index fossils.
A day
Review Geologic Time Scale video notes
Activity 1: Mapping geologic time scale
Activity 2: DE Explore Tab: Evidence of Evolution
Homework:
Online Quiz – Informal (double weight)
Code_LY2TE3_
Page 32
Page 31

52. Closure
How does the Geological Time Scale help scientists to learn about Earth’s past life forms, land forms, and climate?

53. Carbon Dioxide Graphing Activity
Monday, October 13, 2014 Tuesday, October 14, 2014
Monday, October 13, 2014 Tuesday, October 14, 2014
Evidence of Climate Change
Evidence of Climate Change
Essential Question:
1. How do ice cores change over time?
2. How do ice cores tell scientists about Earth’s changing atmospheric makeup?
Carbon Dioxide Graphing Activity
Students analyze the link between atmospheric temperatures and carbon dioxide (CO2) concentrations by looking at ice core data spanning hundreds of thousands of years.
Understand the link between temperatures and CO2 concentrations in the atmosphere
Learn how to analyze patterns from the past and present
Learn how past patterns can help to predict future scenarios
Warm Up:
Using textbook, pg A 51- Read Ice Cores (2 paragraphs)
-Create a KIM card for the vocab word ice core
-Answer the question: How does an ice core provide information about Earth’s history?
Vocabulary Word
Definition
Information and examples
Picture/ Memory Cue
Homework:
Finish Graphs
CO2 Over Time
Temperature Over Time
Page 34
Page 33

54. ICE CORES
Each layer records the concentration of gases and tiny particles in the atmosphere during the time the ice was formed.
Antarctica – Ice core was drilled that measured 3 km. or 1.86 miles long!
Contained air bubbles that showed climate changes for the last 740,000 years.
During that time, Earth had 8 Ice Ages

57. Vocabulary Word Web Carbon Carbon cycle Carbon dioxide Fossil fuel
Greenhouse effect
Greenhouse gas
Ice core
Temperature anomaly 1. 2.
Climate Change Over Time 3. 4.

58. Closure A B What is an ice core? How do ice cores change over time?
How do ice cores tell scientists about Earth’s changing atmospheric makeup?
Explain how ice core and tree ring data provide evidence of climate change over time.
Provide examples (determines how levels of carbon dioxide have changed over time.)