Climate Change Edition

There’s Snow

Place Like Home

page 61

Back to the Future

page 38

Number 14

It’s a Small 

World

page 6

The 

GLAS 

Is 

Half 

Full

page 29
Mr. Anantha Prasad, Northern 

Research Station

Dr. Ge Sun, Southern Research 

Station

Mr. Emrys Treasure, Southern 

Research Station

Dr. Robert Westfall, Pacific 

Southwest Research Station

Collaborating Scientists

Dr. Peter Brown, Rocky 

Mountain Tree-Ring 

Research, Inc.

Dr. Thomas Kitzberger, 

Universidad Nacional del 

Comahue, Argentina

Dr. Dar Roberts, University of 

California Santa Barbara

Mr. Will Summer, North 

Carolina Clean Water 

Management Trust Fund

Dr. Thomas Veblen, University 

of Colorado

With thanks to

Emily Melear-Daniels, Cradle 

of Forestry Interpretive 

Association

Cover photos credits: Connie Millar, National 

Aeronautics and Space Administration, Emily 

K. Heyerdahl, and Ken Curtis.

Natural Inquirer

Produced by

Forest Service

Cradle of Forestry Interpretive 

Association

Production Staff

Babs McDonald, Forest Service

Jessica Nickelsen, Cradle 

of Forestry Interpretive 

Association

Michelle Andrews, University 

of Georgia

Rachel Small, Cradle of 

Forestry Interpretive 

Association

Forest Service

Tom Tidwell, Chief

Jimmy L. Reaves, Deputy 

Chief, Research and 

Development

Jim Hubbard, Deputy Chief, 

State and Private Forestry

Michael Rains, Station Director, 

Northern Research Station

John Sebelius, Staff Director, 

Science Quality Services

Safiya Samman, Staff Director, 

Conservation Education

Mark Twery, Project Leader, 

Northern Research Station

Barbara McGuinness, 

Conservation Education 

Coordinator, Northern 

Research Station

Climate Change Edition • Number 14 • Winter 2011

Cradle of Forestry 

Interpretive Association

Alex Comfort, Executive 

Director

Adam DeWitte, Director of 

Education

Stuart Ryman, Chairman

Forest Service Scientists 

Highlighted in the 

Journal

Dr. Keith Aubry, Pacific 

Northwest Research Station

Mr. Johnny Boggs, Southern 

Research Station

Ms. Diane Delany, Pacific 

Southwest Research Station

Dr. Eileen Helmer, 

International Institute of 

Tropical Forestry

Dr. Emily Heyerdahl, Rocky 

Mountain Research Station

Dr. Louis Iverson, Northern 

Research Station 

Dr. Stephen Matthews, 

Northern Research Station

Dr. Kevin McKelvey, Rocky 

Mountain Research Station

Dr. Steve McNulty, Southern 

Research Station

Dr. Connie Millar, Pacific 

Southwest Research Station

Mr. Matthew Peters, Northern 

Research Station
1

The Natural Inquirer • Number 14

Contents

Editorial Review Boards . . . . . . . . . . . . . . . . . . . . . . . . 2

About the Natural Inquirer . . . . . . . . . . . . . . . . . . . . . . 3

Who Are Scientists? . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Welcome to the Climate Change edition of 

the Natural Inquirer! . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Features:

 It’s a Small World: How Oceans and 

the Climate Can Affect Wildland Fires 

Thousands of Miles Away . . . . . . . . . . . . . . . . . . . . . 6

 Moving on Up: The Possible Impact 

of Climate Change on Forest Habitat . . . . . . . . . . 20

 The GLAS Is Half Full: Satellites and 

Changing Tropical Forests . . . . . . . . . . . . . . . . . . . 29

 Back to the Future: Using Dead Trees 

To Predict Future Climates . . . . . . . . . . . . . . . . . . . 38

 Did They Make the Gradient? Climate 

and Stream Temperatures Now and 

Into the Future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

 There’s Snow Place Like Home: 

Tracking the Range of Wolverines 

Over Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Note to Educators . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Lesson Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Reflection Section Answer Guide . . . . . . . . . . . . . . . 78

Which National Science Education 

Standards Can Be Addressed By 

These Articles? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

What Is the Forest Service? . . . . . . . . . . . . . . . . . . . 85

What Is the Cradle of Forestry 

Interpretive Association? . . . . . . . . . . . . . . . . . . . . 85

38

61

6

29
2

Climate Change Edition, http://www.naturalinquirer.org

Editorial Review Boards

Natural Inquirer editorial review boards hard at work.

“I like the fact that it is useful for people who love science 

and it keeps us focused on our planet and why we 

should help keep it under control.”

“This paragraph is very well written and is easy to 

understand.”

“This is worthwhile! We need to learn about this....We 

need to fix this problem soon.” 

“I think you should put in a lot more information. Kids 

want to know how to tell the age of a tree.”

“Great to know but not everyone cares about GPS 

[global positioning systems] and longitude and 

latitude. Everybody should care, so spice it up a bit.”

“I enjoy how this [Fire Safety Tips] ties into the 

article.”

“Great facts but you need some that WOW us!”

“I think you should put the definitions near the 

words throughout the article.”

 “I like how there is a glossary.”

“Cool, sounds like a cool job!”

Climate Change Editorial Review Boards’ Comments

Oconee County, Georgia Parks and 

Recreation Department, Teen Extreme 

Program, Oconee Veterans Park, 

Kelsey Tate, Assistant Youth Programs 

Coordinator and David Martin, Counselor

Athens-Clarke County, Georgia Leisure 

Services Department, Memorial Park Day 

Camp, Counselors Michael James, Sanjay 

Rema, and Katie McMichael
3

The Natural Inquirer • Number 14

About the Natural Inquirer

Who Are Scientists?

Scientists are people who collect and 

evaluate information about a wide range 

of topics. Some scientists study the 

natural environment. To be a successful 

environmental scientist, you must:

Scientists report their research in 

journals, which are special booklets that 

enable scientists to share information 

with one another. This journal, the Natural 

Inquirer, was created so that scientists can 

share their research with you and with other 

middle school students. Each article tells you 

about scientific research conducted by scientists 

in the Forest Service, U.S. Department of 

Agriculture. If you want to know more about 

the Forest Service, you can read about it on the 

inside back cover of this journal, or you can visit 

the Natural Inquirer Web site at http://www.

naturalinquirer.org.

All of the research in the Natural Inquirer is 

concerned with nature, such as trees, forests, 

animals, insects, outdoor activities, and water. 

First, you will “meet the scientists” who 

conducted the research. Then you will read 

something special about science and about the 

natural environment. You will also read about 

a specific research project, which is written 

in the format that scientists use when they 

publish their research in journals. Then, YOU 

will become the scientist when you conduct the 

FACTivity associated with each article. Don’t 

forget to look at the glossary and the special 

sections highlighted in each article.

At the end of each section of the article, you 

will find a few questions to help you think about 

what you have read. Your teacher may use 

these questions in a class discussion.

b Be curious—Are you interested 

in learning?

b Be enthusiastic—Are you enthused

about an environmental topic?

b Be careful—Are you accurate in 

everything that you do?

b Be open minded—Are you willing 

to listen to new ideas?

b Question everything—Do you think 

about what you read and observe?
4

Climate Change Edition, http://www.naturalinquirer.org

Welcome

to the Climate Change edition of the Natural Inquirer!

I

s the climate changing over time? You 

probably have heard many different 

opinions about climate change. In the 

past few years, most scientists have agreed 

on at least one thing about climate change. 

They have agreed that measured and recorded 

changes in Earth’s climate over the past 100 

or more years point to a warming of Earth’s 

surface greater than they would have expected 

from normal cycles. Normal cyclical (si kli 

kəl) changes in Earth’s ocean currents and 

atmospheric (at mə sfir ik) pressure cause 

changes in weather and climate patterns on land. 

(Read “It’s a Small World” to learn more!)

What are Earth’s normal cycles? 

Scientists have discovered that Earth has 

many different oceanic (ō shē a nik) and 

atmospheric cycles. In this Natural Inquirer, 

you will read about research concerning a 

short-term cycle called El Niño. El Niño is 

part of a cycle that occurs every 4 to 7 years. 

You will also read about cycles that occur 

every 30 to 40 years. Even longer cycles have 

been discovered as well; one of these cycles 

lasts about 1,500 years, and still longer cycles 

last for thousands of years. Each of these 

cycles has a cool phase and a warm phase, 

which occur when Earth’s climate either 

cools a little or warms a little.

Earth’s average temperature depends 

on how much of the Sun’s energy comes 

through the atmosphere to Earth’s surface, 

and how much escapes back into space. 

About 90 percent of the Sun’s energy is 

trapped by gases in the atmosphere, including 

carbon dioxide, methane, and nitrous oxide. 

This trapped energy is sent back to Earth 

in all directions, warming the planet. This 

warming is called the greenhouse effect, 

and the gases are called greenhouse gases. 

Without these gases, humans and other forms 

of life would not be able to survive on our planet. 

During the past 150 years, however, 

the amount of greenhouse gases in the 

atmosphere has risen sharply. This increase 

has been happening since the beginning of the 

Industrial Revolution. Scientists believe the 

sharp rise in greenhouse gases is caused by an 

increase in the burning of fossil fuels, such as 

oil, coal, and natural gas. These higher levels 

of greenhouse gases in the atmosphere trap 

more of the Sun’s heat that is reflected off of 

Earth’s surface. This additional trapped heat 

leads to increasing temperatures on Earth.

Evidence from scientific measurements 

gives scientists more confidence in their 

conclusions about global climate change. 

Every year, global temperatures have been 

rising, the amount of Arctic sea ice has 

been shrinking, and glaciers are getting 

smaller. Scientists are now able to use 

computer programs to track and predict both 

atmospheric and oceanic movements across 

the globe. They are able to see how these 

movements affect short-term and long-term 

weather patterns.

Global climate change is sometimes called 

global warming. Scientists use the term 

“global climate change” because many aspects 

of Earth’s climate are changing. Along with 

rising yearly temperatures, scientists predict 

increases in both droughts and flooding. The 

effects of climate change will be different in 

different places on Earth. Some places will 

experience periods of heavy rain, for example, 

and others will experience periods of low rainfall.

As the global climate changes, we will 

experience changes on Earth. In “Did They 

Make the Gradient?” you will learn what 
5

The Natural Inquirer • Number 14

scientists have discovered about rising stream 

temperatures. As the climate changes, the 

types and numbers of trees and other plants 

will shift where they grow. Some trees and 

plants will die off in areas, and they may grow 

in new areas. A warmer climate with more 

summer rainfall, for example, may cause 

an increase in the growth of grasslands in 

the United States. Trees that grow in the 

Southern United States may begin to grow 

farther north. You will read about how the 

habitat of trees may change in “Moving on 

Up.” The places where animals are found 

will change, in connection with changes in 

vegetation and temperature. One type of 

butterfly, for example, is now found living 

farther north than it lived in the past. In 

“There’s Snow Place Like Home,” you will 

learn how the habitat of the wolverine has 

changed over time.

While humans work to reduce the 

amount of fossil fuels being burned, we also 

must work with the coming changes. To 

do so, scientists and forest managers are 

thinking in the following new ways:

1. Instead of fighting change, work with it. 

Do what you can to reduce the impact 

of climate change, but be prepared for 

change and adapt as needed.

2. Understand that we do not know 

exactly what will happen in the 

future, but we do the best job we 

can using predictions. Sometimes, we 

will make a decision about what to 

do only to discover that later, we may 

have to make a different decision.

3. Accept that the way we did things in 

the past may not be the best choice 

for the future.

4. Focus on the way forests and other 

natural systems live, grow, and 

change, instead of what they look like. 

In this Natural Inquirer, you will learn 

how scientists are using trees that died 

many years ago to predict the future 

(“Back to the Future”). You will also learn 

how information from satellites is helping 

scientists to understand how forests are 

changing on Earth (“The GLAS is Half Full”). 

Although climate change is bringing 

challenges for everyone, it is also helping us 

to think in new ways and do some things 

differently. In this Natural Inquirer, you will find 

suggestions about things you can do to help. 

You might come up with new ideas yourself! 

Every day, every individual has a chance to do 

something to help our environment.

As the climate changes, scientists predict that sea level will rise. 

Photo courtesy of Babs McDonald.
6

Climate Change Edition, http://www.naturalinquirer.org

It’s a Small World:

How Oceans and the Climate 

Can Affect Wildland Fires 

Thousands of Miles Away

Photo courtesy of Emily K. Heyerdahl.
7

The Natural Inquirer • Number 14

Meet the Scientists

Dr. Peter Brown, 

Dendrochronologist 

(den drō krə nä lə jist): 

My favorite science 

experience was 

certainly the earliest I 

can remember. I grew 

up on the Navajo Indian 

Reservation in northern 

Arizona. When I was in second grade, I 

rode a horse out to Keet Seel Ruin to visit a 

dendrochronologist named Jeff Dean. He was 

using tree rings to find the ages of the timbers 

used for construction of the village. Keet Seel 

is a very large and well-preserved cliff dwelling 

built by the Ancestral Pueblo people in the 

13th century (1200s).

Using cross-dating, Dr. Dean documented 

the dates when people cut the trees used in 

their dwellings. Cross-dating is a method used 

to match tree-ring patterns in different trees.

Cross-dating enables dendrochronologists to 

go back in time. This is what tree ring scientists 

do all the time, not only to study archaeology, 

but also to look at past rainfall and many other 

things that influence tree growth.

Dr. Thomas Kitzberger, Biogeographer 

(bī ō jē ä grə fər): My favorite science 

experience is scouting large unexplored 

areas in search of evidence of past fires 

from old trees. It is like time traveling to 

find an old tree with many fire scars. It 

makes you think, “This tree was born way 

before Columbus 

arrived in America.

This tree witnessed 

cultures from which 

humankind does not 

have written reports.” 

Through careful study, 

trees tell stories about 

people and how they 

interacted with their 

environment.

Dr. Emily Heyerdahl, 

Dendrochronologist: My favorite science 

experience is solving ecological puzzles 

about past wildland fires using tree rings.

Just as when I was a young woman, I like 

being outside all summer collecting data 

and samples from trees that were alive 

hundreds of years ago. During the winter 

and in the laboratory, I also take joy in dating 

wood samples with a microscope and in 

exploring data with a computer.

Dr. Thomas Veblen, Physical Geographer: 

My favorite science experience is learning 

what tree rings can tell us about the history 

of insect outbreaks on trees.

t

t

t

t
8

Climate Change Edition, http://www.naturalinquirer.org

Sometimes it is hard 

to study the past. This is 

especially true if the past you 

want to study was hundreds 

or thousands of years ago. It 

is made more difficult if the 

past you want to study has 

no written records. Some scientists, such as 

archeologists (är kē ä lə jists) and paleontologists 

(pā lē än tä lə jists), use items from the past as 

clues. Archeologists usually use human-made 

items, and paleontologists usually use natural clues. 

A dendrochronologist is a scientist who uses the 

natural clues found in tree rings (figure 1).

In this study, the scientists used clues 

provided by old trees to help them understand 

the past. The scientists used information from 

tree rings. As a tree grows, it adds a layer of 

new growth on its trunk. For trees growing in 

dry areas, a lot of growth in a wet year shows 

up as a thick ring. In a dry year, the tree’s 

growth ring is thin. If something happens to the 

tree during a year, scientists can find clues in the 

tree’s growth ring for that year. For example, 

if there was a wildland fire and the tree was 

not burned up or killed, a scar may be evident 

in that year’s growth ring. Clues from a tree’s 

growth rings also help scientists determine the 

past climate of an area, as well as when and 

where wildland fires occurred (figure 2).

Thinking About the Environment

Figure 1. Dendrochronologists are able to date 

Native American historic and cultural sites using 

wood samples. Photo courtesy of Peter Brown.

Figure 2. Tree rings provide clues about a tree’s 

history. On the right, a fire scar was created 

when a surface fire burned near the tree. Photos 

courtesy of Emily K. Heyerdahl and the Forest 

Service.

Thinking About Science

You may have heard the expression, “It’s 

a small world.” It seems hard to believe, but 

many ecosystems on Earth are connected, 

even if they are located far apart. For example, 

glaciers in Arctic regions hold large amounts of 

fresh water when they are frozen and release 

that water when the temperature rises. This 

can cause changes in ocean temperatures and 

currents far from Earth’s Arctic regions. Another 

example is the Gulf Stream, which is a current of 

seawater moving up the eastern North American 

coast and finally eastward to northern Europe. 

Although Norway is located close to the Arctic 

region, the Gulf Stream keeps that country’s west 

coast free of ice all year. 

The oceans, in particular, affect many climatic 

(klī ma tik) and weather events on land. You are 

probably aware of the formation of hurricanes 

and cyclones, which form over ocean waters and 

sometimes reach coastal areas. Scientists have 

discovered that oceans can even affect the 

occurrence of wildland fire. 

The scientists in this study were 

interested in exploring the connection 

between ocean patterns, climate, and 

the timing of wildland fires in the 

Western United States. 
9

The Natural Inquirer • Number 14

What is dendrochronology? 

Dendrochronology is the study 

of “tree time” and is also called 

tree-ring dating. Dendrochronology 

is a science based on the fact that 

every year a tree grows it adds a 

new layer of wood to its trunk; 

this process forms tree rings. Over 

a period of time, these rings form 

a series of light and dark circles 

that are visible on cross-sections 

of cut trees. A cross-section of a 

tree is when you cut a tree down 

and expose the middle of the tree 

(figure 3). 

Often trees are sampled using 

a hand drill, called an increment 

(iŋ krə mənt) borer (figure 4). 

Neither of these techniques kills 

the trees. 

Figure 4. Dendrochronologists 

do not have to kill trees to 

get information from tree 

rings. An increment borer 

allows scientists to pull a small 

sample of the tree’s rings.

The hole created by the borer 

is then sealed to protect the 

tree. The sample is a long, 

thin cylinder of wood. Photo 

courtesy of Edward Cook and 

the National Oceanic and 

Atmospheric Administration 

(NOAA) Paleoclimatology 

Program, U.S. Department of 

Commerce.

Figure 3. Dendrochronologists use chain 

saws to take samples from trees that are 

already dead, like these old stumps. Photo 

courtesy of James P. Riser, II, and Emily K.

Heyerdahl.
10

Climate Change Edition, http://www.naturalinquirer.org

Figure 6a. These two globes show the 

relationship between ocean temperature and 

rainfall during the 1997 El Niño. On the left, 

the darkest streaks shows warmer ocean sea 

surface temperatures. The warm water easily 

evaporates and storms are more likely to form.

On the right, the darkest areas indicate heavy 

rainfall. You can see that heavy rain fell in the 

Pacific Ocean, along the coast of Northwestern 

South America and in the Southeastern United 

States. From the National Aeronautics and Space 

Administration (NASA) Earth Observatory, http://

earthobservatory.nasa.gov.

Figure 6b. These two globes show the 

relationship between ocean temperature and 

rainfall during the 1988 La Niña. On the left, 

the darkest streaks show that sea surface 

temperatures were cool in the east Pacific off 

of the coast of South America. Since cool air 

is dense, it does not rise and storms are not 

likely to form. On the right, the darkest areas 

show places where drought (very low rainfall) 

occurred in Northwest South America and the 

Southeastern United States. The Southeastern 

United States is the area in the United States 

most affected by ENSO. From NASA Earth 

Observatory, http://earthobservatory.nasa.gov.

Introduction

Scientists have identified a number 

of periodic changes in sea surface 

temperatures that affect climate over land. 

The scientists in this study were interested in 

three periodic changes, called oscillations, 

in sea surface temperatures that vary over 

different time scales (figure 5). 

Oscillation Where? How long? Sea Surface Temperature?

ENSO Tropical Pacific Ocean 2 to 7 years Warm and Cool

PDO North Pacific Ocean 20 years Warm and Cool

AMO Atlantic Ocean 60 years Warm and Cool

Figure 5. A comparison of El Niño-Southern Oscillation (ENSO), Pacific Decadal 

Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO).

The most rapid periodic sea surface 

temperature change is called the El NiñoSouthern Oscillation, or ENSO (figures 6a 

and 6b). ENSO changes every 2 to 7 years in 

the tropical Pacific Ocean. The change involves 

a warming or cooling of the water at the ocean’s 

surface. The warm phase of ENSO is called El 

Niño, and the cool phase is called La Niña.
11

The Natural Inquirer • Number 14

Figure 7. PDO and AMO patterns affect drought conditions in the United 

States. Image adapted from the U.S. Geological Survey (USGS).

Figure 8. The Western United States.

Reflection Section

b	 Whatis the question the scientistswere

trying to answer? 

b Do you think therewerewritten records

aboutfire or sea surface temperature

patterns such as ENSO, PDO, and AMO

hundreds of years ago?Why orwhy not?

A second sea surface temperature change 

is the Pacific Decadal (de kə dəl) Oscillation, or 

PDO. PDO changes like ENSO, but only about 

every 20 years, and it occurs in the North Pacific 

Ocean. The sea surface temperature pattern 

that changes the most slowly is the Atlantic 

Multidecadal (mul tī de kə dəl) Oscillation, or 

AMO. It occurs in the Atlantic Ocean and 

changes about every 60 years (figure 7).

These periodic changes in sea surface 

temperature affect 

climate on land. For 

example, during years 

when AMO is in its 

warm phase, the entire 

Western United States is 

generally warm and dry 

(figure 8). These warm, 

dry conditions mean 

wildfires are more likely.

ENSO and PDO 

affect climate in 

different parts of the 

Western United States 

in different ways. For 

example, during years 

when ENSO is in 

its warm phase, the 

Southwestern United 

States is generally cool 

and rainy whereas the Northwest is generally 

warm and dry. During these years, there is less 

chance of wildfires in the Southwest than in the 

Northwest. 

The scientists in this study were 

interested in the relationship between the phases 

of ENSO, PDO, and AMO and when wildfires 

occurred in the Western United States over a 

400-year time span.
12

Climate Change Edition, http://www.naturalinquirer.org

Figure 9. Scientists examined tree-ring fire scars 

from samples already collected. Photo courtesy 

of Peter Brown.

Methods

The scientists studied the period of time 

between 1550 and 1924. They needed three 

kinds of information for the Western United 

States for each year of this 374-year period. 

First, they needed to know what the climate 

was like and how it differed across the area. For 

example, was it dry to the north but wet to the 

south or was it dry everywhere? Second, they 

needed to know the phase of each of the three 

oscillations. Finally, they needed to know when 

and where wildfires burned. 

To get information about climate and sea 

surface temperatures, the scientists used 

information already collected by other scientists. 

From the ring widths of trees living during these 

374 years, other scientists had identified which 

years were rainy and which were dry. Because 

sea surface temperature also affects climate, still 

other scientists had used ring widths from trees 

to identify sea surface temperature patterns. 

In other words, they identified which phases of 

ENSO, PDO, and AMO occurred each year.

Number Crunches

b	 About how many warm phases of the

AMO did the scientists study? About how

many cool phases did they study? How

many would they have been able to study

if they only used written records from

1900 to today?

this database so anyone can use their data 

to study wildfires in the past. The scientists 

used information from the database that was 

collected from more than 4,700 trees whose 

rings had recorded 33,039 fire scars in the 

Western United States (figure 9).

Once they had collected the three kinds of 

information, the scientists identified the climate 

and phase of each oscillation during years when 

many fires occurred all across the Western 

United States and when many fires occurred 

only in certain areas. They used a computer to 

help them with their analysis because there was 

so much information.

To get information about when and where 

wildfires occurred, the scientists once again 

used data that had already been collected. They 

did not need to collect new data because a 

database is available that contains a history of 

wildfires recorded by tree rings. The database 

is like a fire history museum. Scientists from 

around the world give their tree-ring data to 
13

The Natural Inquirer • Number 14

Reflection Section

b	 Why do scientists share their datawith other scientists?Whatis one advantage of sharingdata? 

b Think about howthe scientists gathered information aboutthe past using tree rings.What are

two other naturalresources that contain information aboutthe climate ofthe past?

Wondering about wildfires 

Figure 10. Many trees can survive lots of fires. Fire scars 

are created when a surface fire burns near a tree. Photo 

courtesy of Michael G. Harrington.

You might be surprised to 

learn that fire is a natural 

part of the environment. Fire 

scars in tree rings show that in 

the past, fires burned in some 

forests every 10 to 20 years 

for many hundreds of years. 

Certain ecosystems depend on 

wildland fires to be healthy and 

sustainable. Wildland fires 

help plants grow by replacing 

nutrients into the ecosystem 

from the fire’s ash. There 

are many different types of 

fires. Some wildfires burn at 

low temperatures and burn 

slowly (figure 10). By trying to 

eliminate wildfires in the past, 

we have actually encouraged 

more fires to burn in forests that 

mostly had surface fires in the 

past. Now, forest managers

sometimes start small, controlled 

fires that burn the fuel that is 

close to the ground. These fires 

are called prescribed fires. For 

more information on wildfires, 

check out the Natural Inquirer’s 

two Wildland Fire Editions!
14

Climate Change Edition, http://www.naturalinquirer.org

Findings

The scientists found that it really is a small 

world! They found that the location of wildfires 

was related to the phase of the oscillations 

during the 374-year period they studied. When 

ENSO and PDO were both in their warm 

phases, many wildfires burned in the Southwest 

where it was dry, but few burned in the 

Northwest where it was wet. 

The opposite was also true. When ENSO 

and PDO were both in their cool phase, few 

wildfires burned in the Southwest but many 

burned in the Northwest. AMO had a different 

effect on wildfires. When AMO was in its 

warm phase, wildfires sometimes burned all 

across the Western United States because it 

was dry everywhere.

Scientists can only predict the weather a few 

days in the future. This is not enough to help 

Discussion

The scientists noted that the AMO pattern 

is now entering a warm phase. This will likely 

affect the occurrence of more wildfires in the 

Western United States. Global climate change, 

with rising temperatures, may cause even more 

warming in the Atlantic Ocean. This may 

increase the effect of the AMO even more. 

Reflection Section

b	 In your ownwords, explain howtrees

thatlivedmany years ago have helped

scientists to understandwhatmay happen

in the future.

b Howmight global climate change affect

sea surface temperatures ?

Reflection Section

b	 Nowyou understand that sea surface temperature patterns andwildfires appearto be

connected.What are other natural processes thatmight be connected to each other?

b Do you think theWesternUnited Statesmight havemore frequentwildfires in the future?

Why orwhy not?

us know if or where wildfires are likely to burn 

during the next summer wildfire season. Sea 

surface temperature patterns, however, change 

periodically in ways that scientists can predict 

months or even years ahead. Because these 

oscillations affect climate, scientists can use 

them to predict whether and where wildfires 

are likely to burn in upcoming wildfire seasons.

With climate change, temperatures are likely 

to increase. These warming patterns may also 

increase the chance of wildfires in the Western 

United States. Larger and more frequent 

wildfires may occur as a result. If the patterns 

uncovered by the scientists continue and average 

temperatures continue to rise, people living in the 

Western United States should prepare for the 

possibility of more frequent wildfires in the future. 
15

The Natural Inquirer • Number 14

Fire Safety Tips 

from the Firewise 

Communities 

Program

Do you live in or near a forest? If so, ask 

the adults in your household if they 

have protected the house from a forest fire. 

Here are some fire safety tips you can do to 

protect your homes from fire:

1. Establish a space around your house 

that does not have any combustible 

materials. This space should be at least 

30 feet or 9 meters across. The larger 

the space, up to 130 feet or 40 meters, 

the better protected your house will 

be. Fire is less likely to jump across 40 

meters and ignite new materials.

2. Reduce the amount of vegetation close 

to your home. 

3. Remove or thin overcrowded or weak 

trees near your home. 

4. Cut your grass and other plants 

regularly. 

5. Move woodpiles and building materials 

away from your home. 

6. Keep your roof and yard clean. Clean 

your gutters regularly. Remove dead 

limbs and branches from your yard, and 

from the base of your chimney and deck. 

7. Make sure your address is easy to read 

from the road, and that your driveway 

is large enough for emergency vehicles. 

8. If you have a wood shake roof, replace 

it with a material that is more fire 

resistant. 

9. Recycle your yard waste. 

10. Listen to your local radio and 

TV stations for fire reports and 

instructions.

For more information check out http://

www.smokeybear.com or http://www.

firewise.org

Glossary

archeology (är kē ä lə jē): The scientific study 

of historic or prehistoric peoples and their 

cultures by analysis of their artifacts, inscriptions, 

monuments, and other such remains.

climate (klī mət): The average condition of the 

weather over large areas, over a long time, or 

both.

database (dā tə bās): A comprehensive 

collection of related data organized for 

convenient access, generally in a computer.

dendrochronologist (den drō krə nä lə jist): A 

scientist who studies tree-rings.

drought (draüt): A period of dry weather with 

little or no rain.

forest manager (för əst mə ni jər): Skilled 

individual who takes care of natural resources.

oscillation (ä sə lā shən): A fluctuation between 

maximum and minimum values.

periodic (pir ē ä dik): Happening at intervals 

over time.

sample (sam pəl): Part or piece that shows what 

the whole group or thing is like.

sea surface temperature (sē sər fəs tem pə(r) 

chur): The temperature of the surface layer of sea 

or oceanic water.

weather (we thər): The state of the atmosphere 

with respect to wind, temperature, cloudiness, 

moisture, pressure, etc.

wildland fire (wī(-ə)l(d) land fi(-ə)r): Fires that 

burn in forests, on prairies, or over other large 

natural areas.

Accented syllables are in bold. Marks are from 

the Merriam-Webster Pronunciation Guide
16

Climate Change Edition, http://www.naturalinquirer.org

FACTivity

Time Needed:

1 class period

Materials: • White unlined paper.

• An assortment of crayons. 

Every student will need access 

to black, light brown, dark brown, 

and tan crayons.

The question you will answer in this 

FACTivity is: How do yearly weather 

conditions affect the way a tree’s growth 

rings look? The objective of this FACTivity 

is to learn how to interpret tree rings.

You will gain an understanding of what 

environmental factors can affect tree 

rings, and you will use your creativity and 

knowledge to create a cross-section of 

a tree, based on information given in the 

FACTivity.

Your teacher will provide the following 

background (or you may read it on your own):

In doing the research for this article, the 

scientists used tree rings that had been 

analyzed by dendrochronologists. Tree ring 

analysis requires observation and pattern 

recognition. Each year of its life, a tree 

creates a tree ring that has two parts: a 

light part and a dark part. The light part is 

called the early wood. It is created during 

the spring and early summer when there 

is usually more water available. The dark 

rings are called late wood. The late wood is 

created during the summer and sometimes 

in early autumn. The late-wood rings are 

thinner and darker than the early-wood 

rings because the tree does not grow as 

much during this time. One early-wood and 

one late-wood ring signify 1 year of growth 

for the tree.

Tree-ring width varies with growing 

conditions, for example the rings are wider 

if a lot of water is available, and they are 

thinner during times of low rainfall. Disease 

or an insect invasion can stress the tree 

resulting in less growth and thinner rings.

Fire can leave a scar that will appear in the 

rings (See figures 11-13).

Figure 11. Tree cross-section showing fire scars.

Photo courtesy of Peter M. Brown.
17

The Natural Inquirer • Number 14

Figure 13. Tree cross-section showing years of 

plentiful rainfall and low rainfall. Photo courtesy 

of Peter M. Brown.

Figure 12. Tree cross-section showing insect 

damage. Photo courtesy of Peter M. Brown.

Scientists are able to study yearly weather 

conditions from observing tree rings.

Scientists are also able to observe the tree 

rings and identify when insect invasions and 

damage from storms occurred.

Brainstorm with other students about the 

different events a tree could experience 

during a year of growth. How might the event 

affect the tree rings? For example, drought 

equals thinner tree rings, normal conditions 

will result in thicker tree rings, and insect 

damage could leave a scar and result in 

thinner tree rings.

Scenario: Scientists have the following 

information about the weather and other 

conditions that happened every year during 

the life of one tree. The scientists need your 

help to predict what the tree rings might 

look like during a 25-year period. Here is 

your opportunity to test the skills that many 

dendrochronologists use every day! 
18

Climate Change Edition, http://www.naturalinquirer.org

Refer to the chart below for the yearly 

conditions over the 25 years. Use a sheet 

of paper and crayons. Remember that 

one tree year includes two rings: an earlywood ring and a late-wood ring.

Based on the chart below, draw a crosssection of a tree. Remember that the tree 

rings for each year may look different, 

The 25-year period of information about weather, insect, and fire for one tree.

Year Condition Year Condition Year Condition Year Condition Year Condition

1 Normal 6 Insect 

damage 11 Heavy 

Rain 16 Insect 

damage 21 Fire 

2 Normal 7 Normal 12 Normal 17 Normal 22 Normal

3 Drought 8 Normal 13 Normal 18 Fire 23 Normal

4 Normal 9 Fire 14 Fire 19 Normal 24 Fire

5 Fire 10 Normal 15 Drought 20 Normal 25 Insect 

damage

depending on the weather or other 

conditions for that year.

Compare your completed tree crosssections with other students. Should the 

cross-sections look similar? Why or why 

not? If they do not look similar, how are 

they different? Why are they different?

Key to conditions:

Drought = 

little to no rain 

Normal = 

adequate rain and 

no other major 

problems 

Heavy rain = 

above average 

rain fall

Insect damage = 

invasion by insects 

with damage to 

tree 

Fire = 

hot fire that did not 

kill tree 

Extension

Draw another tree cross-section. This time, consider what a tree might look like 

growing 50 years from now in a changing climate. Explain why you drew the tree 

cross-section the way you did. What yearly weather and other conditions will 

affect tree-ring growth in the future?

For additional information and another FACTivity about dendrochronology, see 

“Back To the Future” in this Natural Inquirer edition.
19

The Natural Inquirer • Number 14

Additional Web 

Resources

NOAA’s El Niño Animations and Graphics

http://www.elnino.noaa.gov/ani.html

Prentice Hall’s Geoscience Animations for El Niño 

and La Niña

http://esminfo.prenhall.com/science/geoanimations/ani 

mations/26_NinoNina.html

NASA’s El Niño for Kids

http://kids.earth.nasa.gov/archive/nino/intro.html

NOAA’s Ocean Temperatures and Currents 

http://www.oar.noaa.gov/k12/html/oceans2.html

National Science 

Education Standards

Standards addressed in this article include:

Science As Inquiry: 

 Abilities Necessary To Do Scientific Inquiry, 

 Understandings About Scientific Inquiry 

Life Science: 

 Populations and Ecosystems, Diversity and 

Adaptations of Organisms

Science and Technology: 

 Understandings About Science and Technology

Science in Personal and Social Perspectives: 

 Science and Technology in Society

History and Nature of Science: 

 Science as a Human Endeavor,

 Nature of Science

Adapted from Kitzberger, T.; Brown, P.M.; Heyerdahl, E.K.; Swetnam, T.W.; Veblen, T.T. 2007. Contingent Pacific-Atlantic Ocean influence on 

multicentury wildfire synchrony over western North America. Proceedings of the National Academy of Sciences of the United States of America. 104: 

543–548. http://www.pnas.org/cgi/doi/10.1073/pnas.0606078104.

Teachers: If you are a 

Project Learning Tree (PLT)-

trained educator, you may 

use Activity #81, “Living with 

Fire” and Activity #86, “Our 

Changing World.”

You can recycle paper and 

cardboard in your classroom and 

at home. Recycling helps keep the 

paper out of landfills and helps 

reduce the amount of carbon dioxide 

produced by burning the paper. You can 

also reduce the amount of paper you 

use by using both sides of the paper or 

by using paper as scrap paper once one 

side has been used.

What You Can Do:

RECYCLE! RECYCLE!
20

Climate Change Edition, http://www.naturalinquirer.org

Moving on Up:

The Possible Impact of Climate 

Change on Forest Habitat

Photo courtesy of Paul Wray, Iowa State University, http://www.bugwood.org.
21

The Natural Inquirer • Number 14

Meet the Scientists

Mr. Matthew Peters, Geographic 

Information Systems (GIS) Analyst (a nə ləst): 

A Geographic Information System, or GIS, 

is a system that collects, stores, manages, 

and presents information that is linked to a 

specific place on Earth. As a GIS Analyst, I 

work with geographic information to help solve 

problems. My favorite science experience has 

been collecting vegetation information in the 

Western United States for a project addressing 

forest fires. I was on a 6-month internship 

with the Student 

Conservation 

Association 

(SCA). During that 

time, I identified 

plant species

in wilderness 

locations to 

improve our 

identification of 

these species 

using satellite data.

Dr. Louis Iverson, Landscape Ecologist: 

My favorite science experience is finding 

out new (to me) patterns, trends, or 

functions of nature.

It really is amazing 

how organisms 

interact with other 

organisms and their 

environment! One 

great way to do this 

is to get out into 

as many places in 

nature as possible.

Mr. Anantha Prasad, Landscape 

Ecologist: My favorite science experience 

is combining what I have learned and 

gaining insights. For example, I like to 

look at information about climate change, 

topography, where different plant 

and animal species are found, and the 

properties of soils in a particular area. Then, 

I can tie these different characteristics of 

the area together to better understand how 

they relate to each other. Dr. Stephen Matthews, Wildlife Landscape 

Ecologist: My favorite science experience is 

coming up with new research questions based 

either on my current work or a new area of 

ecology. Then I like to go out and try to solve 

the problem in an attempt to advance my 

understanding of the natural world.

t

t

t

t
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Climate Change Edition, http://www.naturalinquirer.org

When scientists study climate change, they 

often look toward the future. The job of these 

scientists is to predict what might happen as 

the climate changes over time. Because no one 

knows for sure what will happen in the future, 

predicting it is a big challenge for scientists. 

In general, scientists take two main steps to 

predict what might happen. 

First, they look at past or current situations. 

Often, scientists track what has happened 

over time, from a time period in the past to the 

present. This is called a trend. For example, 

scientists have tracked changes in the average

yearly temperature since 1880 (figure 1).

The second thing scientists do to predict 

the future is create a computer model. A model 

is a mathematical representation of a system. 

For example, consider figure 1. If everything 

continues to be the same in the future as it was 

in the past, scientists can imagine what the line 

in figure 1 might look like in the future. They do 

this by taking the same information collected in 

the past and applying it to the future. Scientists 

studying climate change sometimes use different 

models to represent different possible futures. 

This is because what happened in the past 

might be different than what will occur in the 

future. In the case of rising temperatures, for 

example, scientists might consider both a future 

with a small rise in average temperatures, and 

Thinking About Science

Figure 1. The trend in average yearly 

temperature since 1880. What trend do you see 

in this graph? (From http://data.giss.nasa.gov/

gistemp/graphs/Fig.A3.pdf)

one with a larger rise in average 

temperatures.

In this study, the scientists 

used one model that assumed 

people will continue to burn 

fossil fuels at an increasing 

rate for decades into the future. 

They used another model that assumed people 

will conserve fuels by doing things like driving 

less and using less electricity. In the second 

model, the amount of carbon dioxide emitted 

to the atmosphere was expected to be less than 

the amount emitted in the first model.

Thinking About the 

Environment

Almost everyone lives in a community. Did 

you know that trees live in communities too? 

These communities are different than human 

communities. Forest communities are made up 

of different species of trees that are commonly 

found living in the same area. Foresters name 

these forest communities after the most 

common species of trees living there. 

The scientists in this study were interested 

both in individual species of trees and in forest 

communities. To understand 

how forest communities 

might change in the future, 

the scientists had to study 

individual species of trees. 

They did this because although 

trees in the same community live in the same 

general habitat, some trees can survive in 

other habitats as well. As the climate changes, 

therefore, some trees in the community might 

die off, and others might survive. If this happens, 

the forest community will change.
23

The Natural Inquirer • Number 14

Introduction

Global climate change is likely to affect 

plants worldwide. One type of plant that will 

be affected is trees. Groups of different tree 

species are found together in forests because 

the habitat is well suited to those tree species’ 

survival. Some elements of habitat include 

the amount of yearly rainfall an area receives, 

the average temperature in each season, the 

steepness of the land, the area’s elevation, and 

the type of soil. 

If any of the elements of an area’s habitat 

change, some tree species may not be able 

to survive. For example, if the average 

temperature of the area rises, some trees 

species may not survive long term. If the 

temperature rises, however, in nearby areas that 

had previously been too cold for those species in 

the past, the seeds from those tree species may 

be transported away from the tree, germinate, 

and begin to grow in the new, warmer areas. 

The scientists in this study were interested 

in trees that live in the Eastern United States 

(figure 2). They wanted to explore how the 

habitat of these trees might change in the future 

as the climate 

changes. They 

also wanted 

to know how 

different 

tree species 

might move 

in response 

to a changing 

climate.

Figure 2. The Eastern United States.

How do trees 

move?

As you know, individual trees cannot 

move from place to place. Through 

time and seed dispersal, however, the 

places a tree species lives may change. If the 

climate in a particular area changes, a tree 

species may no longer thrive in that original 

habitat. 

The seeds of trees can spread in many 

ways. Birds and other animals may eat 

the seeds. Later, they will defecate and 

deposit the seeds in a new area. Seeds can 

be carried by animals in their fur or even in 

their mouths and then dropped in another 

location. Seeds are also blown away by 

wind or carried by water. If climate change 

causes the preferred habitat of some tree 

species to move in one direction or the 

other, those tree species, over time, will 

follow the preferred habitat through the 

movement of their seeds. 

Reflection Section

b	 What questionswere the scientists

trying to answer?

b Do you think a changing habitatmay also

affectthe animals thatlive in the Eastern

United States?Why orwhy not?
24

Climate Change Edition, http://www.naturalinquirer.org

Methods

The scientists wanted to predict how 

different tree habitats and forest communities 

in the Eastern United States might change 

over time. Scientists believe that the amount 

of carbon dioxide going into the atmosphere 

affects Earth’s average temperatures. As higher 

levels of carbon dioxide go into the atmosphere, 

the average temperature rises. It is important 

to remember, however, that a certain range of 

carbon dioxide in the atmosphere is necessary 

to support life on Earth. 

The scientists considered two different 

possibilities for future levels of carbon dioxide 

going into the atmosphere. First, they assumed 

that what happened in the past will continue 

to happen in the future. The amount of carbon 

dioxide going into the atmosphere has been 

rising over time. Therefore, the scientists 

assumed that the amount of carbon dioxide 

going into the atmosphere will continue to 

rise in the future. The scientists used existing 

information to estimate future average 

temperatures and future average rainfall in the 

Eastern United States, if this were the case. 

Then, the scientists considered the possibility 

that people will begin to burn less fossil fuels in 

the future. This would mean that lower amounts 

of carbon dioxide would go into the atmosphere. 

The scientists then used existing information 

to estimate future average temperatures and 

future average rainfall in the Eastern United 

States. This time, however, they assumed 

that less fossil fuels would be burned than is 

currently predicted. The scientists considered 

the preferred habitat of 134 different tree species. 

Habitat includes things like the amount of rainfall 

and the average temperature preferred in each 

season by each species. Then, based on the two 

Findings

The scientists discovered that, in both 

possible futures, the preferred habitats of tree 

species may move in a northerly direction. For 

the trees already living in the Northeastern 

United States, some of the preferred habitats 

may shift into Canada (figure 3). For trees 

living in the far Southeastern United States, 

their habitat might move across a larger area of 

the Southern United States (figure 4). 

Regardless of the habitats studied, the 

scientists found that the preferred habitats 

of trees will likely move north if the amount 

of carbon dioxide going into the atmosphere 

continues to increase. Even if people burn less 

fossil fuels in the future, the preferred habitats 

of eastern tree species may move northward. 

They will not, however, move as far north from 

their existing location as compared with the 

other possibility.

possible amounts of carbon dioxide going into the 

atmosphere, they created maps to show where 

the center of the preferred habitat of each tree 

species may be in the future.

Reflection Section

b	 Why did the scientists considerwhatmay

happen if peopleburn less fossilfuels in

the future?

b Whatis one advantage of usingmaps to

showresearch results?
25

The Natural Inquirer • Number 14

Discussion

The forest communities of the Eastern 

United States are likely to change as the climate 

changes. Not all the possible changes are 

considered negative. For example, the habitat 

of some trees may expand. Other tree species, 

however, may experience a loss in habitat, 

which would not be a good thing for those tree 

species. As these changes occur, the forest 

communities will also begin to change.

Along with changes in forest communities, 

there may be increasing chances of threats to 

the trees’ health. Examples include danger from 

invasive animals, plants, and insects. Other 

possible dangers include diseases, fire, floods, 

droughts, and changes in how the land is being 

used by people. 

Reflection Section

b	 Ifthe preferred habitat of sugarmaple

treesmoves fartherinto Canada,what

possible impactmightthis have onU.S.

businesses that sellthe sweet product

ofmaple trees?

b Whywillthe preferred habitats

ofmosttree speciesmove in a

northerly direction?

Figure 3. The center of the preferred habitat for 

sugar maple living in the Northeastern United 

States will move into Canada.

Figure 4. The future preferred habitat for the 

slash pine tree living in the Southeastern United 

States will likely move across the south. In which 

direction is the preferred habitat likely to move? 

The left map was created from Forestry Inventory 

and Analysis data, Forest Service. The right map 

was created using a General Circulation Model 

(GCM) of climate change.

Reflection Section

b	 The scientists consideredwhatmight

happen if peopleburned less fossilfuels

in the future.If peopleburn even less

fossilfuels in the future than the scientists

considered, howmightthe predicted

movement of eastern tree species change?

b	 Whatisonewaypeoplemightrespondtothis

knowledgeofchangingforestcommunities?
26

Climate Change Edition, http://www.naturalinquirer.org

Glossary

average (a v(ə-)rij): The usual kind or amount.

The number obtained by dividing the sum of two 

or more quantities by the number of quantities 

added.

carbon dioxide (kär-bən dī äk sīd): A gas made 

up of carbon and oxygen with no color or smell.

conserve (kən sərv): To avoid wasteful or 

destructive use of something.

defecate (de fi kāt): To have a bowel movement.

dispersal (di spər səl): The scattering or 

spreading in all directions.

elevation (e lə vā shən): The height above sea 

level.

emitted (ē mit əd ): To throw out or eject.

fossil fuel (fä səl fyü(-ə)l): Fuel, such as coal, 

petroleum, or natural gas, formed from the 

fossilized remains of plants and animals.

germinate (jər mə nāt): To start growing or 

developing.

habitat (ha bə tat): Environment where a plant or 

animal naturally grows and lives.

invasive (in vā siv): Tending to spread.

species (spē shēz): Groups of organisms that 

resemble one another in appearance, behavior, 

chemical processes, and genetic structure.

system (sis təm): An ordered gathering of facts 

or processes to form a whole.

topography (tə pä grə fē): Detailed, precise 

description of a place or region. Physical features 

that make up the topography of an area include 

mountains, valleys, plains, and bodies of water.

Accented syllables are in bold. Marks are from 

the Merriam-Webster Pronunciation Guide.

FACTivity

Time Needed

2 class periods

Materials needed per 

student group:

• Tree identification books (and/ 

or Internet access) and other 

resources about trees.

• Two blank maps of the United States.

• Two pieces of blank white 

8.5” X 11” paper.

• Markers.

The question you will answer in this 

FACTivity is: What is the geographic 

distribution of a particular tree species? 

Process for each 

student group: 

First class period:

Choose a tree species that you would like 

to study that lives in the United States. Use 

a tree identification book, the Internet, or 

the library.

Research information about this tree 

species. Find the following information 

about the tree:

Where is the tree species’ habitat? When 

you find out about the areas in which it 

lives, mark those areas on one of the blank 

maps provided. Label this map “Current 

Geographic Distribution of [tree species].”

• What is the climate of the current 

habitat for the tree species?

• What is the average size of a tree of 

that species?

• What does the tree look like?

• What is the expected life span of 

the tree species?

• Do any invasive plants or insects threaten 

the tree species?
27

The Natural Inquirer • Number 14
28

Climate Change Edition, http://www.naturalinquirer.org

Additional Web 

Resources

U.S. Environmental Protection Agency’s Carbon 

Cycle Movie

http://www.epa.gov/climatechange/kids/carbon_cycle_

version2.html

World Almanac for Kids’ Carbon Cycle

http://www.worldalmanacforkids.com/WAKI-View 

Article.aspx?oldpin=xca041350a&pin=x-ca041350a

The Great Plant Escape- Seed Germination

http://urbanext.illinois.edu/gpe/case3/index.html

Student Conservation Association 

http://www.thesca.org

National Science 

Education Standards

Standards addressed in this article include:

Science as Inquiry: 

 Understandings About Scientific Inquiry

Life Science: 

 Regulation and Behavior,

 Populations and Ecosystems,

 Diversity and Adaptions of Organisms

Science in Personal and Social Perspectives:

Risks and Benefits

Because keeping carbon emissions down 

will help the environment, maybe you could 

ride your bike or walk to school. Make 

sure it is safe to do so. If you can’t walk or 

ride your bike, take the school bus or have 

your family carpool with other 

families in the neighborhood.

Adapted from Iverson, L.R.; Prasad, A.M.; Matthews, S.N.; and Peters, M. 

(2007). Estimating potential habitat for 134 eastern U.S. tree species under 

six climate scenarios. Forest Ecology and Management. 254: 390-406.

If you are a PLT-trained 

educator, you may use Activity 

#22: “Trees as Habitats,” 

Activity #77: “Trees in Trouble,” 

and Activity #85: “In the 

Driver’s Seat.”

Second class period:

Use this information and any other 

interesting facts to create a Tree Fact File.

The Tree Fact File should be displayed on 

two 8.5- X 11-inch pieces of paper.

One map should have already been filled 

out with the current areas where the tree 

species is found. You will use the other 

map to make a prediction about where 

you think the tree species will live as the 

climate becomes warmer. Think about 

what you read in the article to help you 

make this map. Label this map “Predicted 

Geographic Distribution of Tree Species.” 

As you make this map, think about your 

own predictions about how much fossil 

fuels will be burned in the future.

Once all of the groups have created 

a Tree Fact File and completed the two 

maps, the files and maps can be compiled 

into a class book.

After answering the question posed at 

the beginning of this FACTivity, consider 

and discuss this question: “Why is it 

important to predict the future condition of 

our natural resources?”

Extensions

If you have already read or will 

read “There’s Snow Place Like Home,” 

compare your maps of the tree species 

geographic distribution with the 

wolverine article animal geographic 

distribution.

• How are the maps similar?

• How are the maps different?

• What conclusions can you draw from 

comparing these maps?

What You Can Do: What You Can Do:
29

The Natural Inquirer • Number 14

The GLAS is Half Full:

Photo courtesy of

Satellites and Changing 

Tropical Forests

Image courtesy of the National Aeronautics and Space Administration.
30

Climate Change Edition, http://www.naturalinquirer.org

Meet the Scientists

Dr. Dar Roberts, Geographer: 

My favorite science experience 

was climbing a 44-meter tall 

tower to access tree canopies.

I had a $70,000 instrument strapped on me to 

measure how light changes from the ground to the 

top of a forest. I have other favorite experiences, of 

course. I enjoyed flying in a small plane less than 

500 meters over the Amazon rain forest, renting a 

small boat in Brazil where we saw sloths and pink 

dolphins, and building my own 20-meter tower to 

access tree canopies, then climbing it.

Dr. Eileen Helmer, Ecologist: I have 

two favorite science experiences. The first 

was collecting field data on 

horseback in Costa Rica 

after a hurricane caused 

landslides that blocked most 

of the roads. The second was 

climbing Nevis Peak on Nevis 

Island in the Caribbean to find 

out how high on the mountain 

the cloud forests occurred.

All life on Earth depends on sunlight to 

survive. Humans, however, also use light for 

convenience and to meet modern needs. In 

recent years, the use of light has increased. Light 

is used not just for human needs and comfort; it 

is also for science and technology. 

In the 1950s and 60s, light began 

to be used to improve electronic 

communications. Today, optical 

fibers are used for most landbased electronic communications. 

Light is also used in satellite 

technology to communicate 

between Earth and space. In 2003, a satellite 

was launched carrying an instrument called 

the Geoscience Laser Altimeter (al ti mə tər)

System, or GLAS. GLAS sends 40 beams of 

light every second to Earth’s surface. GLAS 

provides continuous light beam observations of 

Earth. When each light beam reaches Earth, it 

is reflected back to the satellite. By tracking and 

recording the amount of time each beam of light 

takes to return to the satellite, GLAS can be used 

to calculate many properties of Earth’s surface.

In this research, the scientists used GLAS to 

estimate the increase over time in living material, 

such as branches and leaves, in young and growing 

tropical rain forests. If this kind of research is 

successful, scientists will have a more accurate way 

to understand the world’s rain forests.

Thinking About Science Thinking About the 

Environment

When a large amount of carbon dioxide, or 

CO2, is emitted into the air, it gets trapped 

in the atmosphere and causes the surface of 

Earth to warm beyond its normal range. This 

is happening now, partly because of the large 

amount of fossil fuels being burned for energy. 

Carbon, one of the elements that makes 

up CO2, is found in every living thing. As trees 

grow, for example, they absorb carbon from the 

atmosphere. Old forests also absorb and hold 

carbon. Because trees keep carbon on Earth, 

they help to reduce the rate of global warming. 

Scientists need to know the location and 

age of forests to estimate how much carbon 

they absorb and hold. To do this, scientists 

must calculate how much living and once-living 

material, called biomass, is contained within 

a forest area. They also need to calculate how 

much the biomass of young forests is increasing 

as they grow. The amount of carbon absorbed 

and held by forests is related to the amount of 

biomass contained in the trees 

and other vegetation that make 

up the forests. If a forest has 

more trees, leaves, and other 

vegetation, it keeps more 

carbon on Earth.
31

The Natural Inquirer • Number 14

Introduction

In the past, when scientists wanted to learn 

about a forest, they had to visit the forest in 

person. Although this first-hand knowledge of 

forests provides good information, it also limits 

the amount of information scientists can collect. 

It takes a lot of time and money to do research 

about forests in person, especially if the forests 

are located far away from home. In addition, the 

Earth is too large and forests too widespread for 

scientists to visit all of the forests. 

Scientists are working to understand how 

forests across the world can help to address 

climate change. To do this, however, they need 

a more efficient way to study large areas 

of forest land. One way to do this is to use 

technology to help them do their research. 

They also need to know that the technology 

that they use will provide the same quality of 

information they would get if they studied each 

forest in person. 

The scientists in this study wanted to 

discover whether information gathered by 

satellites could be used to identify the age 

of tropical rain forests and to estimate the 

increase in the amount of biomass in growing 

rain forests. They also wanted to know if 

information gathered by satellites could be used 

to estimate the amount of biomass held by old 

rain forests. The scientists wanted to know if 

the information gathered by satellites was as 

good as the information they would get if they 

gathered it in person. 

Methods

The scientists decided to study an area in the 

Amazon rain forest of Brazil (figure 1). They 

decided to use this area because it contained 

both young and old tropical rain forests. They 

also used this area because other scientists had 

already collected the same information by doing 

research in person within the forests. 

First, the scientists located forests in the 

Rondônia area. Then, for each forest they 

located, they estimated the forest’s age. They 

did this to identify which forests were young and 

which were old. Young forests are those growing 

on land that had previously been cleared and had 

been either replanted in trees or allowed to grow 

back naturally. Any forest under 50 years old 

was considered a young forest.

The scientists used images from Landsat 

satellites to locate and estimate the age of each 

forest (figure 2). Landsat satellites contain 

technology that takes photographs of Earth as 

Figure 1. The scientists used data collected 

from forests in the State of Rondônia, Brazil, 

South America. Locate the State of Rondônia on 

the map using lines of latitude and longitude.

Latitude and longitude are imaginary lines used 

to locate places on Earth. Lines of latitude are 

parallel to the Equator, and lines of longitude 

connect both of Earth’s poles. Rondônia is 

located 10 degrees South, 64 degrees West. 

Is Rondônia located in the eastern or western 

part of Brazil?

Reflection Section

b	 What questionswere the scientists

trying to answer?

b How do you think using information

gathered by satellites could be more

efficient than collecting information

in person?
32

Climate Change Edition, http://www.naturalinquirer.org

Figure 2. A Landsat satellite. Image courtesy of 

NASA.

Figure 4. The height of trees. Younger trees are 

usually shorter than older trees. Which tree has 

more biomass?

the satellite orbits the planet (figure 3). The 

scientists used Landsat images of the Rondônia 

area taken between 1975 and 2003. They used 

photographs of the same forest areas taken over 

the 28-year period.

The scientists used an algorithm to 

estimate each forest’s age, which was based 

on the images taken over the 28 years. The 

algorithm’s instructions were entered into a 

computer program. The computer program, 

following the algorithm’s instructions, identified 

the changing color of the forests over time. As 

a forest ages, it changes from lighter to darker 

green. As a result, the computer program was 

able to use Landsat images, taken over a period 

of years, to estimate each forest’s age.

Then, the scientists estimated the increase in 

the amount of biomass in each of these growing 

forests. To make these estimates, the scientists 

needed to know something about the height of 

the forest’s trees (figure 4). They used another 

satellite to get this information.

Figure 3. A Landsat image of South America.

Locate Brazil in this image. Now find Rondônia.

(See figure 1 if you need help.) 
33

The Natural Inquirer • Number 14

The scientists used data from a special 

satellite called the Ice, Cloud, and Land 

Elevation Satellite, or ICESat (figure 5). 

This satellite carries special equipment called 

the Geoscience Laser Altimeter (al ti mə tər) 

System, or GLAS (figure 6).

Figure 5. ICESat logo. Image courtesy of the 

National Aeronautics and Space Administration.

Figure 7. As ICESat orbits Earth, GLAS sends 

beams of light to Earth’s surface. ICESat travels 

at 16,000 miles per hour and 370 miles above 

Earth.

Figure 6. GLAS equipment was placed on 

the ICESat. Image courtesy of the National 

Aeronautics and Space Administration. 

As ICESat orbits Earth, GLAS sends 40 

light beams every second to an area of Earth’s 

surface. These light beams reflect off of Earth’s 

surface and back to the satellite (figure 7). 

GLAS’s computer calculates how long it takes 

each beam of light to return to the satellite. 

Based on this information, scientists are able to 

identify the height of forest trees (figure 8).

Figure 8. Scientists can calculate the height of 

trees based on the time it takes a light beam to 

travel from the ICESat satellite to Earth and back 

to the satellite. Scientists can do this because 

they know how fast light travels. The speed of 

light is 186,282 miles per second.
34

Climate Change Edition, http://www.naturalinquirer.org

Remember that the scientists had already 

calculated the approximate age of each forest 

studied. Using another computer program and 

now knowing the forests’ age and height, the 

scientists then estimated how much the biomass 

was increasing in young forests as they grew 

over time. They also estimated how much 

biomass was contained in old forests. The 

scientists then compared this information with 

the same information that had been collected 

by scientists working in person within the 

Rondônian forests.

Reflection Section

b	 Why did the scientists study an area

that had already been studied by other

scientists working within the forest?

b Do you think the information collected

by the satellites is exact or an estimate?

Why or why not?

Reflection Section

b	 Think about your own achievement of accuracy on a test. Is an 88-percent accuracy rate

acceptable? Consider that the satellites collect a lot more data from all across the planet

than scientists could collect by visiting forests in person. Do you think an accuracy rate of

88 percent is acceptable? Why or why not? 

b Based on the results of this research, would you say that data collected by satellites may

one day be used to help estimate the amount of carbon being held by the world’s forests?

Why or why not?

Findings

For estimates of the forests’ age, the scientists 

found that the algorithm’s evaluation of Landsat 

photographs was 88 percent accurate. The 

algorithm had difficulty distinguishing some 

forms of agriculture and recently cleared forest 

land from young forests. Although there were 

some errors, the 88-percent accuracy rate was 

considered acceptable. 

The satellite and computer estimates of 

the increasing amount of biomass in young 

forests was similar to the estimates made 

by scientists working within the forests. For 

some areas of the old forests, the satellite 

and computer estimates of the amount of 

biomass were smaller than what scientists had 

measured within the forests themselves. The 

scientists who did this study believe, however, 

that this difference can be explained by where 

the actual forest measurements were taken. 

When scientists were measuring biomass in 

person, they measured forests far from human 

disturbances that received more rainfall. This 

meant that the trees they measured were larger 

than trees closer to human disturbances, and 

therefore had more biomass. 

The scientists then compared their estimates 

of biomass over the entire Rondônia area, 

including young and old forests, with estimates 

made by those studying the forests in person. 

They found that computer estimates made 

from the satellite data were similar to the overall 

estimates made within the forests of Rondônia.
35

The Natural Inquirer • Number 14

Discussion

The scientists doing this research studied 

tropical rain forests in the relatively flat areas 

of Western Brazil. They discovered that 

data gathered by satellites led to the same 

information as that gathered by scientists 

working within those same forests. They 

concluded that satellites can be used to study 

tropical rain forests in relatively flat areas. They 

do not know, however, if the method that they 

used to interpret the satellite images can be 

Reflection Section

b	 The scientists did not claim that their methods could be used to study all forests.

Why do you think they did not make this claim?

b From a climate change perspective, why is it important to understand how fast the

amount of biomass increases in young tropical rain forests?

used to accurately collect the same type of 

information from drier, less forested, or more 

mountainous areas.

Tropical rain forests provide some of the 

most diverse habitats for plants and animals 

worldwide. They also contain a lot of biomass, 

which means that they keep a lot of carbon on 

Earth. It is important to understand as much as 

possible about Earth’s rain forests. With the help 

of satellites and computer technology, scientists 

can study rain forests all around the world.

Glossary

algorithm (al gə ri thəm): A step-by-step 

procedure for solving a problem that often 

involves a computer program. Usually, an 

operation is repeated over and over until the 

problem is solved.

biomass (bī ō mas): All the living and recently 

living things in a particular area.

data (dā tə): Factual information used as a basis 

for reasoning, discussion, or calculation.

efficient (i fi shənt): Bringing about the result 

wanted with the least amount of time, waste, 

or materials.

emit (ē mit): To throw out or eject.

fossil fuel (fä səl fyü(-ə)l): Fuel, such as coal, 

petroleum, or natural gas, formed from the 

fossilized remains of plants and animals.

habitat (ha bə tat): Environment where a plant 

or animal naturally grows and lives.

interpret (in tər prət): To explain or tell the 

meaning of.

optical (äp ti kəl): Relating to vision or to light.

pigment (pig mənt): A coloring matter in 

animals and plants. A substance that gives 

color to a material.

Accented syllables are in bold. Marks are from 

the Merriam-Webster Pronunciation Guide.
36

Climate Change Edition, http://www.naturalinquirer.org

FACTivity

Time Needed

35 minutes

Materials needed per 

student group:

• One sheet of blank paper, 8.5- X 11-inch.

• Crayons or colored markers (brown, 

black, red, orange, yellow, and gray).

• Stapler.

• Scissors.

The question you will answer in this 

FACTivity is: How can a series of Landsat 

images help scientists estimate a forest’s 

age over time? 

Process: 

Cut the sheet of paper into 8 equal pieces.

Staple one side to make a small book.

Number each sheet of paper in the lower 

right hand corner. The first page will be 1, the 

next page will be number 10. Then number 

each page in increments of 10 (20, 30, 40, 

and so on, until you have numbered all of the 

pages). Draw a large empty circle on each 

page.

Each of these numbers represents a 

person’s age, from age 1 to 70. The circle 

represents the top of a person’s head, as if 

you were looking down at them from above.

Think for a moment of a person’s hair 

color. Hair gradually loses its pigment and 

becomes white (or gray) as a person ages.

Now color the circle (the top of a person’s 

head) for each age. You decide when your 

person starts to get some gray hairs. Over 

time, your person becomes completely gray.

Make this as realistic as possible, based on 

when you think most people’s hair starts 

to become gray, and when it becomes 

completely gray.

As a class, complete the chart below. 

(You may put this chart on the whiteboard 

or blackboard.)

According to your class, at which age 

are people most likely to see their first gray 

hairs? At which age are they most likely to 

become about half gray? At which age are 

people most likely to become completely 

gray? If you had a stack of photographs of 

the tops of people’s heads, how could you 

use this activity’s results to help you assign 

an age to each head?

Compare this activity with the use of 

Landsat images in the study you just read.

How are they similar? How are they different? 

Answer the question posed at the beginning 

of the FACTivity. What in this FACTivity is 

similar to the actions of scientists working 

within forests on the ground? What makes 

them similar?

Age of person 1 10 20 30 40 50 60 70

Number of heads showing their first 

gray hairs

Number of half-gray heads

Number of completely gray heads
37

The Natural Inquirer • Number 14

National Science 

Education Standards

Standards addressed in this article include:

Science as Inquiry:

 Abilities Necessary To Do Scientific Inquiry,

 Understandings about Scientific Inquiry 

Earth Science

 Structure of Earth System

Science and Technology

 Understandings about Science and Technology

Science in Personal and Social Perspectives

 Science and Technology in Society

History and Nature of Science

 Science as a Human Endeavor,

 Nature of Science

Adapted from Helmer, E.H.; Lefsky, M.A.; and Roberts, D.A. 2009. Biomass accumulation rates of Amazonian secondary forest and biomass of old-growth 

forests from Landsat time series and the Geoscience Laser Altimeter System. Journal of Applied Remote Sensing. Vol. 3, 033505. http://www.tropicalforestry.

net/Members/ehelmer/2009-mapping-amazonian-forest-type-age-and-secondary-forest-biomass-accumlation-rates-from-landsat-time-series-and-glas/.

If you are a PLT-trained 

educator, you may use Activity 

#86: “Our Changing World.”

“The GLAS is Half Full” was taken from a well-known question: “Is the glass half 

empty or half full?” It is thought that people who see the positive side of things will 

say that a half-filled glass is half full. People who see the negative side of things 

will say that a half-filled glass is half empty. In reality, you cannot label a person as 

positive or negative from his or her answer to just one question.

Additional Web 

Resource

Video Clip of Deforestation in Rondônia, Brazil 

http://www.youtube.com/watch?v=CwPq1CBTAx0 

For every plastic and paper bag 

created, some CO2 was emitted 

into the atmosphere. One easy 

way you can help to reduce 

the amount of CO2 going into 

the atmosphere is to carry 

reusable cloth bags with you 

when you go to a store. If you do 

not have a reusable bag with you and 

you only need to buy a few items, you 

don’t have to use a bag at all! Another 

easy way to reduce energy use, and, 

therefore, carbon emissions is to take 

the stairs instead of the elevator. What 

is one other thing you can easily do to 

reduce the amount of energy you use?

For more information about carbon 

and forests, see the Natural Inquirer 

“World’s Forests” edition, Inquiry 3: 

“How Much Carbon Is Being Held By 

the World’s Forests?”

What You Can Do: What You Can Do:
38

Climate Change Edition, http://www.naturalinquirer.org

Back to the Future:

Using Dead Trees To Predict 

Future Climates

Photo courtesy of Connie Millar.
39

The Natural Inquirer • Number 14

Meet the Scientists

Dr. Robert 

Westfall, 

Quantitative 

Geneticist (kwän tə 

tā tiv jə ne tə sist): Dr.

Millar and I were 

searching for pika 

in a boulder field 

on Warren Bench, 

above Mono Lake, 

California. Pika are 

small mammals in 

the same family as 

rabbits. We noticed tips of pine branches on 

the ground. This was evidence of pika because 

they like to eat the tender pine branches. Then, 

I found more pine tips hidden in the rocks.

Dr. Millar and I wondered how the little pika 

got the pine tips because most of the pine 

branches were so high off the ground. I looked 

in a clump of pines up from the rocks—no 

clipped tips on the ground. Then I looked at 

a bunch of clipped pine branches that were 

6 feet off the ground. The little pika had 

scampered across the deep snow that spring 

to collect the needles and tender spring buds.

Dr. Connie Millar, Research Climate 

Ecologist: Recently, I had a great science 

treasure hunt in the wild lands of Nevada.

We were looking for the lowest elevation

living bristlecone pine. The bristlecone pine 

is known for its long life. These trees can live 

more than 5,000 years. The tree that we were 

hunting for had been documented in a remote 

canyon in 1984. We had a picture of the tree 

and knew its general whereabouts, but even 

though we searched and searched we couldn’t 

find it.

We kept trying to match the picture to the 

canyon, and, finally, I ran ahead to an old dead 

skeleton of a tree. Sure enough, there were 

disintegrated bristlecone pine cones on the 

ground. We cored the 

tree and found that 

it had died during a 

drought more than 

10 years ago. We are 

determined to set 

another low-elevation 

record with a live 

bristlecone pine! 

Ms. Diane Delany, Biological 

Technician: When I was a little girl I loved 

to collect things in nature. I collected 

rocks, shells, bird nests, and pine cones. I 

collected them everywhere I went. I would 

sort my collections, put them in order, and 

look for patterns. Now that I am a scientist, 

my favorite scientific experiences are those 

where I am collecting, observing, and 

taking notes with the smell of the trees 

and the mountain air all around me. I love 

working with our team of scientists to find 

answers in our observations, collections, 

and data.

t

t

t
40

Climate Change Edition, http://www.naturalinquirer.org

Often, scientists have to understand the past 

to predict what might happen in the future. The 

scientists in this study examined trees that died 

during a volcanic explosion in 1350. How many 

years ago was that? The scientists wanted to 

discover what the climate was like during the 

trees’ lifetime. They wondered if knowing this 

would help them to make predictions about our 

future climate. 

Thinking About 

the Environment

Volcanoes are powerful forces 

of nature that can quickly change 

the way Earth looks. In this 

study, many trees were killed 

by an eruption from Glass Creek Vent in 

the Inyo Craters in California (figure 1). A 

vent is the opening of a volcano through which 

magma comes to the surface. After they were 

killed, the trees near the Glass Creek Vent 

were preserved by tephra that came from 

the explosion of the volcano. Tephra is the 

volcanic rock that is blasted into the air from the 

explosion (figures 2a and 2b). The amount of 

tephra can vary widely. Between 1 and 8 meters 

of tephra fell on the area that the scientists 

studied, burying the lower portions of the tree 

trunks. These well-preserved tree trunks helped 

the scientists learn a lot about this area’s past. 

Figure 1. The area the scientists studied.

Figure 2a and 2b. Notice how the tephra covers 

the land under the trees and partially buries the 

tree trunks. Photos courtesy of Connie Millar, 

Forest Service.

Climate change is a topic 

that scientists are interested in 

understanding. Climate change 

refers to the change in Earth’s 

climate over time. One way to 

predict our future climate is to understand the 

patterns of past climates, including those long 

ago and those more recently. Think of one other 

situation where learning about the past can help 

us to predict the future. 

Thinking About Science

Number Crunches

b	 How many feet of tephra fell? Multiply the

number of meters by 3.28 feet.
41

The Natural Inquirer • Number 14

Introduction

The tree line is the edge of a habitat at which 

trees are capable of growing (figure 3). In this 

study, the scientists wanted to examine dead 

trees that they found above the current tree 

line. These dead trees are known as deadwood. 

The deadwood found above the current tree 

line indicated that the climate during the trees’ 

lifetime was different than it is now. The 

scientists were interested in learning about the 

climate that existed when these trees were alive. 

Methods

The scientists studied two areas close to 

Glass Creek Vent. One area was Whitewing 

Mountain and the other area was San Joaquin 

Ridge (figure 4). To better understand the 

area, the scientists created a map that showed 

the location of all deadwood in the area. The 

scientists identified the location where the 

deadwood was greater than 1 meter in length 

and 10 centimeters in diameter (figure 5). They 

only mapped deadwood located above the 

current tree line. They mapped 1,675 dead trees 

from Whitewing Mountain and 60 from San 

Joaquin Ridge.

Figure 3. Notice the line above which trees 

cannot grow. Photo courtesy of Connie Millar, 

Forest Service.

Figure 4. Whitewing Mountain. Photo courtesy 

of Connie Millar, Forest Service.

Figure 5. Trees varied in size and length. Photo 

courtesy of Connie Millar, Forest Service.

Reflection Section

b	 What was the question the

scientists were trying to answer?

b	 Think of an example of something that

happened to you in the past that helped

you better understand something in the

future.For example, last week you did not

study for your science quiz and failed, so

this week you studied.

b Why did the existence of the dead trees

above the tree line indicate that the

climate might have been different when

the trees were alive?
42

Climate Change Edition, http://www.naturalinquirer.org

Figure 6. Tree rings tell a story about the tree.

Tree rings show how old a tree is and provide 

clues to what the environment was like during its 

lifetime.

Reflection Section

b	 Why did the scientists only map the

deadwood above the tree line?

b How did technology help the scientists in

this study?

The scientists used a Global Positioning 

System (GPS) to determine the location of 

each piece of deadwood. In addition to mapping 

the deadwood, the scientists examined the 

tree rings (figure 6). The tree rings helped the 

scientists understand how old the trees were 

and how well they grew. The tree rings also 

helped the scientists to learn about the climate 

conditions in which the trees were growing. The 

study of tree rings to help understand climate 

and the environment is called dendrochronology 

(den drō krə nä lə jē). You will learn more about 

dendrochronology in the FACTivity at the end 

of this article.

A Global 

Positioning 

System, or

You probably are familiar with a 

GPS. You might even have one in 

your family car! A GPS tells your exact 

location on Earth’s surface, based on the 

lines of latitude and longitude. Latitude 

and longitude are imaginary lines on 

Earth, and are included on most globes 

and many maps. A GPS unit gives the 

unit’s location by communicating with 

GPS satellites orbiting Earth. At any one 

time for any location on Earth, 4 of the 

24 GPS satellites are above the horizon. 

The GPS unit communicates with three 

of the satellites. Each satellite sends 

information to the unit. The unit receives 

information from all three satellites, and 

then displays the unit’s location.

GPS

Photo courtesy of United States Army.
43

The Natural Inquirer • Number 14

Findings

The scientists found that a variety of trees 

had lived above the tree line. Some of the types 

of trees included whitebark pine, sugar pine, 

western white pine, lodgepole pine, Jeffrey 

pine, and mountain hemlock (figures 7-10). 

These species 

currently grow 

much lower in 

elevation than 

the Whitewing 

summit where 

the deadwood 

occurs. The 

scientists found 

that the climate, 

when the trees 

were alive, was 

much warmer 

and slightly drier 

than the area’s 

Figure 7. Whitebark pine.

Photo courtesy of Dave Powell, 

http://www.bugwood.org. 

Figure 9. Lodgepole pine. Photo courtesy of 

Dave Powell, http://www.bugwood.org. 

Figure 8. Sugar pine. Photo courtesy of Connie 

Millar, Forest Service.

Figure 10. Mountain hemlock. Photo courtesy of 

Donald Owen, http://www.bugwood.org.

current climate. The mean annual temperature 

was warmer by 3.2 degrees Celsius, annual 

precipitation was 24 millimeters less.
44

Climate Change Edition, http://www.naturalinquirer.org

Discussion

The scientists discovered that their climate 

findings from the past were similar to climate 

projections for California between 2070 and 

2099. In earlier climate change projections, 

other scientists thought that an increase in 

temperature would cause a decrease in the 

amount of forest land. 

The scientists in this study, however, found 

that a variety of trees were living in a warmer 

climate and at a higher elevation than they are 

currently found. Therefore, the scientists think 

that the predicted future decrease in forested 

area may not be as great as some earlier studies 

suggest. They predicted that the location where 

the trees may be found in the future will likely be 

different and the tree line will likely move higher. 

Number Crunches

b	 How many degrees warmer was it in

Fahrenheit? To calculate, multiply the

degrees Celsius by 9/5, and then add 32.

b	 What was the precipitation loss in inches?

To calculate, multiply the number of

millimeters by 0.039.

Reflection Section

b	 The scientists measured the change in

temperature in Celsius. Why did they

use Celsius to measure and report

temperature rather than Fahrenheit?

b Why are these findings important to

our understanding of the future?

Reflection Section

b	 Based on this article and your own

experience, why do you think it is

important to study the past?

b Why do you think scientists try to predict

things that will happen in the future? For

example, why do you think scientists want

to know what trees may be alive in the

future as the climate becomes warmer?

Glossary

annual (an yü əl): Covering the period of 1 year.

climate (klī mət): The average condition of the 

weather over large areas, over a long time, or 

both.

core (kȯr): To use a hollow drill to take a small 

cylindrical sample of a tree’s trunk.

elevation (e lə vā shən): The height above sea 

level.

Global Positioning System (GPS) (glō bəl 

pə zi shə ning sis tem): A radio satellite navigation 

system that allows users to determine their 

position on Earth’s surface.

mean (mēn): The average in a set of numbers.

precipitation (pri si pə tā shən): Rain, hail, snow, 

mist, or sleet that falls on Earth.

preserve (pri zərv): To keep free from decay.

Accented syllables are in bold. Marks are from 

the Merriam-Webster Pronunciation Guide
45

The Natural Inquirer • Number 14

FACTivity

Time Needed

2 to 3 days

Materials needed for 

each group of two to 

four students:

• A copy of the sample tree-ring cores on 

page 47.

• One 1-meter strip of adding machine 

tape or thick ribbon.

• Colored pencils and markers.

• Reference material, such as almanacs, that 

provide students with the dates of social, 

cultural, environmental, and scientific 

events over the past five decades.

• A notebook for recording results 

(optional).

• Tape and scissors.

The question you will answer in this 

FACTivity is: How does dendrochronology 

help us understand the environment in 

which a tree lives?

Day 1:

In this FACTivity, tree-ring core samples 

showing the tree-ring patterns of four trees 

are represented by four strips on page 47.

You can imagine what real cores look like 

if you take a straw and draw one of the 

patterns on the straw. These cores are taken 

from a tree using an instrument borer. An 

instrument borer is a hand drill that pulls out 

a thin cylinder of wood from the trunk of a 

tree. The borer must go all the way to the 

center of the trunk to accurately read the 

tree-ring patterns. After the core sample is 

pulled, scientists seal the hole so the tree is 

protected from insects and disease.

Using the four core samples on page 47, 

each group will construct the climatic (klī ma

tik) history of the trees. You will then record 

social, cultural, environmental, and scientific 

events that occurred during the lifetime of 

these four trees.

Process: 

1. Read the background information 

provided at the end of this FACTivity.

2. Make sure your group of students has 

a copy of the four tree core samples 

printed on page 47.

3. Imagine that you have tree core samples 

from:

Sample 1: A living tree that was cored this 

year in Oakwood Forest.

Sample 2: A log found near the main trail 

in Oakwood Forest. The log was 

cored four years after it fell.

Sample 3: A tree that was cored 1 year 

before it was cut down in 

Oakwood Forest.

Sample 4: A barn beam from Oakwood 

Hollow Farm. The beam was 

cored this year.

4. Cut the tree core samples into four strips.

5. The left side of each tree core sample 

represents the first year of growth of the 

tree. The right side represents the bark 

and, just to its left, the year the tree core 

sample was pulled. The tree rings are 

represented by the rectangles making 

up each strip.

6. Each year of growth is represented 

by a larger light-colored “ring” and a 

smaller dark-colored “ring.” The larger 

light-colored ring represents fast spring 

growth and the smaller dark-colored 

ring represents slower summer (and 

sometimes autumn) growth. Beginning 

with Samples 1 and 2, match the tree ring 

patterns and tape the two strips together.

Continue this by adding Samples 3 and 

4. Sample 1 represents the youngest tree 

and Sample 4 represents the oldest tree 

that was sampled.
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Climate Change Edition, http://www.naturalinquirer.org

Now, on the strips, 

7. Write the current year in space provided.

8. Counting backwards from the current year, 

identify the years each tree was cored. To 

keep track, write any year where you find 

room on the strip.

9. Identify the year Sample 4 tree began to 

grow and write it in the space provided.

10. Complete the following chart: Age of tree Year tree was cored

Year growth 

began

Sample 1

Sample 2

Sample 3

Sample 4

 

11. Look for patterns in the rings. Answer the 

following questions:

a. In what years was there low rainfall or 

other unfavorable growing conditions?

b. What 2 years were the most favorable 

for tree growth? What might have 

happened in those years to support tree 

growth?

c. What overall patterns do you notice in 

the year-to-year weather patterns?

Day 2:

12. Make a timeline. Spread out the adding 

machine tape. Beginning at the left end 

of the tape, record each year from the 

earliest year identified on the tree-ring 

samples through the current year. After 

the years are recorded on the strip, 

identify years that were good growing 

years for the trees in Oakwood, and years 

that were poor growing years. Think of 

other events that might have happened 

during this time period such as birthdays, 

Presidential elections, important scientific 

discoveries, environmental events, cultural 

or social events, and record-setting sports 

achievements. Fill them in on the timeline.

Color the timeline and illustrate it with 

drawings, photographs, or newspaper 

clippings.

13. Here are some follow-up questions.

• Which ring on which trees represents 

your birth year?

• What kind of growing season existed 

that year in Oakwood?

• What buildings in your area were built 

during the lifetime of these trees?

Optional: 

Before doing this FACTivity, the teacher 

may simulate tree core samples using 

straws. The “tree rings” may be drawn on 

the straws, based on the “core strips.” If 

straws are used in place of the strips, each 

group of students should be given a set of 

four straws.
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The Natural Inquirer • Number 14

FACTivity
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Climate Change Edition, http://www.naturalinquirer.org

FACTivity

Background

Dendrochronology is the study of 

tree rings to learn about climatic and 

environmental changes in an area 

surrounding a tree. Each year’s tree-ring 

width is unique. They are like a barcode.

From these rings, scientists can work 

backward from the present to determine 

climate conditions where the tree lived.

Using this technique, scientists can date 

trees that have been dead for centuries.

The tree rings help tell a story about climate 

because the width of the tree ring indicates 

something about the climate. For example, 

narrower rings indicate poor growing 

conditions and wider rings indicate more 

favorable growing conditions.

Reading Tree Rings

Tree rings are formed from the center of 

the tree outward. The ring closest to the bark 

is the youngest and final growth ring. The ring 

closest to the center of the tree is the oldest 

and first growth ring. Neither the outer layer 

of bark nor the central pith layer of a sample 

is counted when determining the age of a 

sample.

Similar ring patterns are found between 

trees growing under the same conditions.

The most obvious feature of these patterns 

is varying widths. Widening of a ring 

indicates good growing conditions, and 

narrowing indicates poor conditions.

Conditions can include climatic factors 

such as temperature and moisture and 

factors such as erosion, insects, fire, 

landslides, etc.

This FACTivity is adapted and reproduced with 

permission from U.S. Geological Survey (USGS).

The activity can be found in USGS’s Global Change 

Teacher Packets. This activity and others can be 

found at http://egsc.usgs.gov/isb/pubs/teacherspackets/globalchange/globalhtml/time.html 

Note: For more in-depth background information 

and a teacher’s guide, please visit the Web site 

listed above. This Web site is linked from the Natural 

Inquirer Web site 

at http://www.naturalinquirer.org.

Extension

Find and map the locations of 

some of the oldest known trees in 

your neighborhood. Sketch what you 

think a core from one of these trees 

might look like. To help you, research 

the weather history of your area.

Contact your local forestry service 

or science museum and obtain some 

actual cross-sections of trees that 

have been cut in your area. Use the 

techniques applied during this activity 

to “read the tree.” If a tree has been 

cut in your neighborhood recently, 

look at the tree rings on the stump or 

ask if you can keep a small piece of 

the trunk.

Create some simulated core straws 

of your own for another group to 

analyze and report about.
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The Natural Inquirer • Number 14

FACTivity Extension

Additional Web 

Resources

USGS Pictures of Inyo Craters

http://lvo.wr.usgs.gov/gallery/InyoCraters_1.html

USGS History of Eruption

http://lvo.wr.usgs.gov/InyoEruption/index.html

NOVA Anatomy of a Volcano

http://www.pbs.org/wgbh/nova/volcano/anat_06.html

EPA’s Kids Climate Change 

http://www.epa.gov/climatechange/kids/index.html

Arbor Day’s Life of a Tree

http://www.arborday.org/kids/carly/lifeofatree/

National Park Service’s Webrangers 

Dendrochronology Activity

http://www.webrangers.us/activities/

dendrochronology/?id=04

National Science 

Education Standards

Standards addressed in this article include:

Science as Inquiry:

 Abilities To Do Scientific Inquiry,

 Understandings About Scientific inquiry

Life Science: 

 Populations and Ecosystems,

 Diversity and Adaptation of Organisms

Science and Technology:

 Understandings About Science Science and 

Technology

Science in Personal and Social Perspectives:

 Science and Technology in Society,

 Natural Hazards

History and Nature of Science: 

 Science as a Human Endeavor,

 Nature of Science

See the light! Use compact fluorescent light 

bulbs. These energy-efficient bulbs help 

fight climate change because they reduce 

the amount of fossil fuels that utilities burn.

You will save 100 pounds of carbon 

for each incandescent bulb that you 

replace with a compact fluorescent 

bulb, over the life of the bulb. (From 

http://www.nature.org/initiatives/

climatechange/activities/.)

Adapted from Millar, C.I.; King, J.C.; Westfall, R.D.; Alden, H.A.; and 

Delany, D.L. (2006). Late Holocene forest dynamics, volcanism, and 

climate change at Whitewing Mountain and San Joaquin Ridge, Mono 

County, Sierra Nevada, CA, USA. Quaternary Research. 66: 273–287. 

http://www.treesearch.fs.fed.us/pubs/31776#.

If you are a PLT-trained 

educator, you may use Activity 

#76: “Tree Cookies” and #40: 

“Then and Now.”

For more information about dendrochronology, see 

“It’s a Small World” in this edition of the Natural 

Inquirer.

Students may compare and contrast 

“Moving On Up” (page 20, this edition) 

with this article in a class discussion.

What You Can Do: What You Can Do:
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Climate Change Edition, http://www.naturalinquirer.org

Did They Make 

the Gradient?

Climate and Stream Temperatures 

Now and Into the Future

Photo courtesy of Ge Sun.
51

The Natural Inquirer • Number 14

Meet the Scientists

Dr. Ge Sun, Research Hydrologist (hī drä lə jist): 

My favorite science experience is getting my ideas 

and study results published in scientific journals.

That way, they will be recorded and hopefully 

used by future generations to understand their 

environment and improve their lives. I come to work 

every day with excitement because I meet bright 

people with good ideas and I learn and see new 

things around the world. Most importantly, I am 

excited about my work because I can contribute to 

solving problems and can answer questions to make 

people happy.

Mr. Johnny Boggs, Biological Scientist: 

My favorite science experience is having the 

opportunity to continuously explore how and why 

our environmental system works the way it does.

Growing up as a kid, I used to hunt, fish, and farm, 

so I have always felt a connection to nature and 

natural resources. In my current position, I offer 

scientific stories in the form of published papers.

I hope these papers add further understanding 

to how our environment will respond to future 

changes and offer a benefit for future generations.

Dr. Steve McNulty, Ecologist: My favorite 

science experience is when I am analyzing 

data and learn something that no one else 

has ever known before. It’s sort of like being 

the first person to ski down a mountain of 

fresh snow, or being the first person to canoe 

down a remote river. This photo was taken on 

a recent trip to China. To the left and in the 

middle are Dr. Ge Sun, Hydrologist, and Dr.

Jim Vose, Ecologist. Dr. Sun and Dr. Vose are 

also Forest Service scientists. You can read 

more about Dr. Vose’s research in the Natural 

Inquirer “Woolly Bully” monograph (http://

www.naturalinquirer.org).

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Climate Change Edition, http://www.naturalinquirer.org

Meet the Scientists

Mr. Will Summer, Forest Hydrologist: My 

favorite science experience is being outside 

during a rainstorm. As a forest hydrologist, I 

study what happens to water from the time 

it falls from the sky until it gets to a stream.

During a rainstorm is the best chance I have 

to really understand what is happening. Did 

you know that only a tiny fraction of rainfall 

falls directly on a stream? Most of it falls 

on land and must travel along the ground’s 

surface or through the 

soil to get to the stream.

Everything the water 

encounters as it flows 

towards the stream will 

affect how clean the 

water is when it gets to 

the stream. That is why 

understanding hydrology 

is so important to 

keeping our streams and 

rivers clean.

Mr. Emrys 

Treasure, Forestry 

Technician: My 

favorite science 

experience happens 

almost every day.

I learn something 

new by testing my 

beliefs about how 

the natural world 

works. These are 

often quite simple 

observations 

about the water 

cycle, how trees grow, or how soils 

form. Sometimes these thoughts lead 

to a breakthrough in understanding 

more complex aspects of the natural 

world, including the impacts of climate 

change. It is through this step-by-step 

process that science and scientists 

solve problems.

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continued from page 51

Thinking 

About Science

Scientific knowledge usually 

advances in small steps. When 

similar results are reported by 

different scientists, scientists 

have more confidence that the 

results are accurate. When scientists generally 

agree that existing results are accurate, they do 

new studies to push their knowledge even further. 

For example, scientists agree that a change in 

air temperature will cause a change in stream 

temperature. Scientists also generally agree that if 

the air temperature in an area rises, then stream 

temperatures in the area will likely rise as well. 

In this study, the scientists wondered if the 

shape of a stream would also affect the stream’s 

temperature. In other words, they wondered if 

the temperature of some streams would change 

more than other streams, if the temperature rose 

by the same amount and the only difference was 

the stream’s shape. The scientists designed a 

study to answer this question.

You can see that scientists develop specific 

questions to answer. Research advances our 

knowledge one question at a time. Scientists are 

like detectives who must answer one question 

before they can move to the next. 
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The Natural Inquirer • Number 14

Introduction

If the temperature of a stream rises too high, 

the animals that live in the stream may find it 

difficult to survive. Big changes in a stream’s 

daytime temperature as compared with its 

nighttime temperature may also cause a problem 

for aquatic animals. It is important, therefore, 

for daytime stream temperatures to stay as low 

as possible. 

Thinking 

About the 

Environment

Streams are found all over 

the world. Streams are waterways that carry 

water to rivers, and rivers carry water to 

oceans. Streams provide habitat for many 

animals, including invertebrates, fish, reptiles, 

amphibians, birds, and mammals. To provide 

habitat for animals, the water temperature 

of streams must not exceed an upper limit. 

The State of North Carolina has determined 

that mountain and upper Piedmont streams 

must not be higher than 29 degrees Centigrade 

(figure 1). The State has also determined that 

the temperature should not be higher than 32 

degrees Centigrade for lower Piedmont and 

coastal streams and rivers.

Many things affect a stream’s temperature. 

The amount of shade over a stream may affect 

its temperature. The air temperature also 

affects a stream’s temperature. What else might 

affect a stream’s temperature? The scientists 

in this study were interested in discovering 

as much as they could about what causes a 

stream’s temperature to rise during the day. You 

may be surprised at what they discovered!

Number Crunches

b	 What is the upper temperature limit of

North Carolina streams in Fahrenheit?

To calculate, multiply the degrees in

Centigrade by 9/5 and then add 32.

Figure 1. North Carolina is in the Southeastern 

United States.

In a natural forest ecosystem, streams are 

protected from high daytime temperatures 

by natural processes. First, trees and other 

plants growing beside the stream provide 

shade from the Sun. Second, the depth of the 

stream may affect its water temperature, with 

deeper streams generally cooler than shallow 

ones. Another process that affects stream 
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Climate Change Edition, http://www.naturalinquirer.org

temperatures is the way water comes into the 

stream. If a stream is fed by an underground 

spring or by groundwater, the cooler water 

from underground may keep the stream’s 

temperature cooler, at least in that area. 

People can affect some of these natural 

processes. For example, people might remove 

trees from a streambank, allowing more sunlight 

to reach the stream. This would raise the 

stream’s temperature. Another way people 

might affect stream temperatures is through 

Reflection Section

b	 What do you think determines the shape of a stream?

b Do you think that a rise in the average air temperature would cause a rise in a stream’s

water temperature? Why or why not?

Methods

The scientists studied four watersheds in the 

Piedmont area of North Carolina. A watershed 

is an area of land where all of the water that is 

under it or drains off of it goes into the same 

place (figure 2). Two of the watersheds 

Figure 2. A watershed. Image from http://www.

kidsgeo.com.

Figure 3. The four watersheds studied by the 

scientists were located in two areas indicated by 

the circle and the triangle. One watershed was in 

the Carolina Slate Belt, and the other was in the 

Triassic Basin.

activities that result in global climate change. If 

the average air temperature continues to rise in 

an area, a stream’s temperature will likely rise too. 

The scientists in this study were interested 

in answering three questions: (1) How does 

the shape of a stream affect its daytime water 

temperature? (2) How does the shape of a 

stream affect the difference between its daytime 

and nighttime water temperatures? (3) How 

might a rise in average air temperature over time 

affect a stream’s water temperature?

contained rocks that formed from the deposits 

of ancient volcanoes and minerals. The other 

two watersheds contained rocks formed from 

the deposits of mud, sand, silt, and gravel 

that were carried away by mountain streams 

millions of years earlier (figure 3). Although the 

geology of these areas was different, the areas 

were only 8 kilometers apart.
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The Natural Inquirer • Number 14

Figure 5. Different stream gradients. Photos courtesy of Babs 

McDonald.

Number Crunches

b	 How far apart were the watersheds in

miles? To calculate, multiply 8 times .621.

The scientists first located the stream in 

each watershed. Then, they located the area 

closest to the stream’s beginning. This is called 

the stream’s headwaters. The 

scientists placed equipment 

in the stream’s headwaters 

to measure the amount 

of streamflow (figure 4). 

Streamflow is the rate at which 

water passes a given point in 

a stream. The scientists also 

measured the height of each 

streambank and the stream’s 

depth. They measured how 

much of the stream was 

covered by the leaves of trees. 

A thermometer was placed in 

each stream to measure water 

temperature. Every 10 minutes, 

this equipment automatically 

measured and recorded the 

amount of streamflow and 

the water temperature. Each 

stream’s gradient was also 

measured (figure 5). 

On the bank nearby, 

weather equipment measured 

and recorded things like air 

temperature, solar radiation, 

rainfall, and humidity. The 

weather equipment recorded 

the data every 10 minutes. The 

scientists then used a computer 

program to compare each of 

the weather measurements 

with daytime and nighttime 

stream temperatures. They 

also compared daytime and 

Figure 4. A flume was placed in each stream to measure the 

amount of streamflow. You can see the differences in the two 

streams. Forest Service photo.

nighttime stream temperatures with streamflow 

and the amount of leaves covering and shading 

the stream (figure 6).

The scientists then used a computer 

program to investigate what effect an increase 

in air temperature would have on the streams’ 

temperatures. They assumed everything else 

was the same, except that they added 2 degrees 

Centigrade to each air temperature value.
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Climate Change Edition, http://www.naturalinquirer.org

Figure 6. The scientists compared daytime and 

nighttime stream temperatures with weather 

information and stream properties.

Figure 7. A fisheye lens and a computer 

program were used to calculate the amount of 

shade over the stream. Forest Service image.

Stream Temperatures

Daytime water temperatures (measured and recorded every 10 minutes)Nighttime water temperatures (measured and recorded every 10 minutes)

Weather and Stream 

Properties

 Weather data (measured 

every10 minutes, recorded 

every hour):

• Air temperature

• Amount of solar radiation

• Amount of rainfall

• Humidity 

Height of streambank

Depth of stream

Gradient of stream

Amount of streamflow (measured and recorded every 10 

minutes)

Amount of shade over the 

stream (measured once using 

a fisheye lens) (figure 7)

Reflection Section

b	 Why do you think the scientists

studied streams that were near each

other but had a different geology?

b Why was it important to study streams

with similar day-to-day weather?

b Look at figure 6. Why did the scientists not

compare the two variables represented

by the lower right rectangle? Which

other variable in this figure would not

be compared with nighttime water

temperatures?

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The Natural Inquirer • Number 14

Reflection Section

b	 Why do you think the most shaded

streams had the lowest daytime

summer temperatures?

b Why do you think that stream

temperatures in a future warmer

climate might rise more in the winter

than the summer? (Hint: think about

what is different about many of

the trees along streambanks in the

summer and winter.)

Reflection Section

b	 Think back to the first question in

the first Reflection Section. Did you

or your class consider the gradient of

the stream as one way to describe its

shape? Do you agree that the gradient

of a stream is part of its shape? Why or

why not? 

b Most States have laws that protect

streams and rivers. These laws prohibit

the removal of trees and other plants

within a certain number of feet from

the water’s edge. Do you think this is a

good thing? Why or why not?

Findings

The scientists found that the most shaded 

streams had the lowest daytime temperatures 

during the summer. They also found that for all 

streams, the difference between daytime and 

nighttime temperatures was greatest during the 

summer. When the scientists compared the 

stream’s temperature with the stream’s gradient, 

they found that the steeper the gradient, the 

lower the water temperature. 

The scientists also found that if the air 

temperature were to rise 2 degrees Centigrade 

over time, stream temperatures would likely rise 

between 0.6 and 1.0 degrees Centigrade.

Discussion

The scientists believe a stream’s gradient 

affects its temperature in this way: When the 

gradient is steeper, molecules of water stay in 

any area of the stream for a shorter period of 

time because of gravity pulling them quickly 

downstream. The heat energy in each of the 

water molecules is carried away before it can 

affect the stream’s temperature. 

A stream’s gradient is a result of the geology 

of the area. Gradient is also one way to describe 

the stream’s shape. The shape of a stream 

affects both its daytime temperature and the 

difference between daytime and nighttime 

temperatures. The steeper the gradient, the 

lower the daytime temperature, which means 

there is less difference between nighttime and 

daytime temperatures.

Although people cannot change the gradient 

of a stream, they can plant and protect trees 

along a stream’s banks. This will help keep the 

daytime stream temperature lower. Although 

stream temperatures in the North Carolina 

Piedmont may rise in the future as the climate 

changes, they are not predicted to go higher 

than the upper limit for healthy streams set by 

the State of North Carolina. 
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Climate Change Edition, http://www.naturalinquirer.org

Glossary

aquatic (ə kwä tik): Growing or living in or upon 

water.

average (a v(ə rij): The usual kind or amount.

The number gotten by dividing the sum of two 

or more quantities by the number of quantities 

added.

ecosystem (ē kō sis təm): Community of plant 

and animal species interacting with one another 

and with the nonliving environment.

flume (flüm): A sloping channel for directing the 

flow of water.

geology (jē ä lə jē): Earth’s matter, including 

its materials, structure, physical properties, 

dynamics, and history, and the processes by 

which Earth’s matter is formed, moved, and 

changed.

gradient (grā dē ənt): The rate of sloping upward 

or downward.

groundwater (graund wä tər): Water that sinks 

into the soil.

habitat (ha bə tat): Environment where a plant or 

animal naturally grows and lives.

invertebrate (in vər tə brət): An animal with no 

spinal column. About 95 percent of all animals 

are invertebrates. These include all animals 

except mammals, birds, reptiles, amphibians, and 

fish.

Piedmont (pēd mänt): An area of land lying at or 

near the base of a mountain range. In the Eastern 

United States, the Piedmont area lies between 

the Appalachian Mountains and the Atlantic 

coastal plain.

solar radiation (sō lər rā dē ā shən): 

Electromagnetic energy from the Sun; sunlight.

variable (ver ē ə bəl): Thing that can vary in 

number or amount.

Accented syllables are in bold. Marks are from 

the Merriam-Webster Pronunciation Guide.

FACTivity

Time Needed

1 class period

Materials needed:

• Three clear 1-quart plastic containers 

(or four for extension). A plastic soft 

drink bottle will work, but the tops 

should be cut so that the opening is 

at least 3 inches across.

• Two aquarium thermometers (or four 

for extension).

In this FACTivity, you will answer the 

following question: Does the movement 

of water affect its temperature?

You may do this FACTivity in pairs 

or in groups, depending on how many 

thermometers and containers are available.

First, develop and write a hypothesis 

for this FACTivity. You should develop your 

hypothesis based on your reading of this 

article and a review of the FACTivity. A 

hypothesis is an educated guess about 

something. Your hypothesis should take the 

form of a specific statement, and it should 

be written as if no change is expected as a 

result of the experiment. It should also be 

something you can test in an experiment.

The following is an example of a hypothesis: 

“A glass of water left in the Sun for 3 hours 

will not have a higher water temperature than 

a glass of water left in the shade.”

After you have read the article and 

reviewed the FACTivity, write your hypothesis on a piece of paper.

Test your hypothesis using the following 

process:

Perform this experiment outside on a 

sunny and warm day.
59

The Natural Inquirer • Number 14

Fill two of the plastic containers with 

water up to 3 inches from the top. Use 

water from a refrigerated water fountain or 

refrigerated water. The water must be cooler 

than the outdoor air temperature, and the 

water must come from the same source 

at about the same time. The temperature 

of the water should be exactly the same 

in each container. If the two samples vary 

at all, mix them together and then divide 

the water between the two containers. Put 

one water-filled container in the Sun and 

place a thermometer in the water. Record 

the beginning water temperature after 3 

minutes, then every 3 minutes until the 

temperature has raised 2 degrees.

At the same time a student, holding one 

filled container and one empty one, should 

stand in the Sun close to the area where 

the first water container has been set. The 

student will pour the water continually from 

container to container. If more students want 

to be involved, a relay may be set up. The 

important thing is to keep the water moving 

from container to container while in the Sun.

Continue pouring the water back and forth 

until the water in the “still” container has 

raised 2 degrees.

Using the second thermometer, measure 

the water temperature of the “moving” water.

Is it 2 degrees warmer than its starting 

temperature? Why do you think it is the 

temperature that it is? Has your hypothesis 

been proven true or false? What is the answer 

to the question posed at the beginning of this 

FACTivity? Do the results of your experiment 

agree with the results in the research you just 

read? Develop and write an explanation of 

your results. How is this FACTivity similar to 

and different from the scientists’ research?

Assessment

Collect students’ written hypotheses and 

explanations of results. Use the rubric below 

to assess their work.

HYPOTHESIS Included in report? Clearly written? Grammar/punctuation 

correct/no mistakes?

In form of statement? Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt)

In form of null hypothesis (no change 

expected)?

Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt)

Is hypothesis testable? Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt)

RESULTS

Written statement of results? Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt)

Stated whether hypothesis is proven 

true or false?

Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt)

Provided answer to FACTivity question? Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt)

Stated whether results agree with 

article research?

Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt)

Provided written explanation of results? Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt) Yes (1 pt) No (0 pt)

Scoring categories: 0-6, 7-12, 13-19, 19-24 (0-6=Lowest achievement, 19-24=Highest achievement)
60

Climate Change Edition, http://www.naturalinquirer.org

Additional Web 

Resources

More possible impacts of climate change on streams:

http://www.sciencedaily.com/releases 

/2009/07/090723142116.htm

http://www.sciencedaily.com/releases 

/2007/05/070504101355.htm

National Science 

Education Standards

Standards addressed in this article include:

Science As Inquiry: 

 Abilities Necessary To Do Scientific Inquiry,

 Understandings About Scientific Inquiry

Earth Science:

 Structure of Earth System

Science and Technology: 

 Understandings about Science and Technology

History and Nature of Science: 

 Science as a Human Endeavor,

 Nature of Science

Adapted from Boggs, J.L.; Sun, G.; McNulty, S.G.; Swartley, W.; Treasure, E.; and Summer, W. 2009. Temporal and spatial variability in North Carolina 

Piedmont stream temperature. AWRA 2009 Spring Specialty Conference, May 4-6, Anchorage, AK. http://www.srs.fs.usda.gov/pubs/ja/ja_boggs005.pdf.

If you are a PLT-trained 

educator, you may use Activity 

# 38: “Every Drop Counts.”

Be a stream detective! Around your home, 

school, and community, notice whether 

streams and rivers have trees and other 

plants growing near their banks. If not, begin 

a campaign to grow and care for trees and 

other plants along waterways. Always have 

an adult you know and trust with you when 

you begin your detective work. Also, always 

get permission from the landowner to walk 

on his or her private land. In addition, you 

can create posters to educate adults about 

the importance of having trees and other 

plants near waterways.

Extension

Repeat the experiment in the shade.

Compare all four temperatures.

What You Can Do: What You Can Do:
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The Natural Inquirer • Number 14

There’s Snow 

Place Like Home:

Tracking the Range of 

Wolverines Over Time

Photo courtesy of Ken Curtis.
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Climate Change Edition, http://www.naturalinquirer.org

Meet the Scientists

Dr. Kevin McKelvey, Wildlife Ecologist: My 

favorite experience was digging out a wolverine 

snow-den in Glacier National Park. To study 

wolverines, scientists capture wolverine kits (baby 

wolverines) and put tracking instruments on them.

These instruments help us follow their movements.

To put the instruments on them, we first dig down 

through the snow to the wolverine den site. The 

den site is usually under about 8 feet of snow and 

under large rocks or downed trees. To find the 

dens, we have to look for wolverine tracks.

I was lucky enough to follow tracks that led to 

the den. The den was visible by a small hole in the 

snow. I was digging down, with the surface of the 

snow about 2 feet above my head when I broke 

through into the center of the den. Immediately, 

I heard the mother wolverine growling right 

beneath my feet. I had this image of an enraged

female wolverine crawling up my leg and gnawing 

on my head. But Mr. Jeff Copeland, who has years 

of experience with wolverines (but who was also 

standing safely on top of the snow) said: “It will be 

fine.” It ended up being fine.

We were able to capture the two kits, 

and conditions were perfect for putting the 

instruments on them 

without causing them 

a lot of stress. We 

had to work quickly 

with mom circling 

about 50 meters away, 

waiting for us to be 

done! (In the picture, 

the wolverine kit is 

covered with a blanket 

to protect its eyes 

while we are studying 

it. The wolverine kit 

was released back to 

its mother when we 

were finished.)

Dr. Keith Aubry, Research Wildlife 

Biologist: One of my most interesting 

and exciting science experiences 

occurred last winter when I traveled 

around the island of Tasmania (which 

is part of Australia). This was my 

first opportunity to experience the 

diversity of marsupials (pouched 

mammals) and monotremes

(egg-laying mammals) that occur 

in the Australian region. I saw 

and photographed a Tasmanian 

devil, ringtail and brushtail 

possums, a Bennett’s wallaby (a 

small kangaroo), and a wombat (a 

chunky, herbivorous marsupial). I 

also learned all about the extinct

Tasmanian tiger. One of my most 

memorable experiences was watching 

an echidna (one of only two egglaying mammals in the world) hunt for 

bugs in decaying leaves and under 

rotting logs. The echidna (also called 

a spiny anteater) looks like a slightly 

deflated soccer ball that is covered 

with poisonous spines!

t

t
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The Natural Inquirer • Number 14

It is important for scientists to gather correct information or data about the topic 

they are studying. Not all information is reliable information. Scientists, therefore, 

need to be able to determine whether the data they are collecting are reliable. In 

this study, scientists gathered information from museums, literature, and archived

material at State and Federal buildings. Once they gathered all their information, they 

did not use any that was unreliable or not well documented. When scientists (or you) use the Internet, 

care must be taken to know the source of the information. Usually, it is best to use Internet sites from 

State and Federal Governments (.gov), universities (.edu), or trusted sites like National Geographic.

If the scientists in this study did not feel confident about their data source, they did not use that 

information. As a result, some information that may have been useful was lost. It is important for 

scientists to keep accurate and reliable data so that their findings will be correct. You have heard your 

teacher ask you to carefully write down your observations and data during experiments at school. 

Now you can see why that is important! 

Thinking About the 

Environment

The Endangered Species 

Act is a law that was created 

in 1973 to protect species 

that are threatened with or in 

danger of extinction. There 

are many reasons a plant or 

animal species may be placed 

on the endangered species list. For 

example, an animal’s habitat may be getting 

smaller because humans are building their houses 

Number Crunches

b	 How old is the Endangered Species Act?

Thinking About Science

in that area. If an animal loses its habitat, it may 

not be able to survive in another habitat. In this 

study, scientists examined wolverine habitat to 

see what things may be shrinking the wolverine’s 

geographic range. Their geographic range is 

where wolverines are found across the United 

States and Canada. 
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Climate Change Edition, http://www.naturalinquirer.org

Methods

The scientists gathered information about 

wolverine trapping and sightings between 1801 

and 2005. They also gathered information about 

wolverines from museums. Each record included 

geographic information identifying where the 

wolverines were seen. The scientists divided the 

records into three time periods— 

• 1995–2005 (current) 

• 1961–1994 (recent)

• 1801–1961 (historical)

 The scientists used computer software to create 

maps with the data. The scientists also collected 

information about the type of vegetation in the area. 

They collected information about climatic (klī ma tik) 

conditions over time and about the spring snow 

Figure 1. The wolverine is well adapted for living 

in snowy environments. By looking at the picture, 

name one adaptation the wolverine has to allow 

it to live in the snow. Photo courtesy of Keith 

Aubry.

Figure 2. In the lower 48 States, the wolverine’s 

current range (1995–2005) is restricted to 

northern portions of the western mountains.

The scientists studied wolverine habitat in these 

States.

Reflection Section

b	 What questions were the scientists

trying to answer?

b	 What are some other animals that

burrow or make dens for their

homes?

Introduction

Wolverines, the largest terrestrial member 

of the weasel family, are mammals that are 

difficult to find (figure 1). Because they live in 

areas far from humans and human development, 

therefore, not much is known about these 

mammals. Wolverines are primarily scavengers, 

and they sometimes travel great distances in a day 

in search of food or shelter. In North America, 

they are currently found in most of Alaska and 

Canada, but only in the mountainous northern 

portion of the lower 48 States (figure 2). 

Wolverines may seek shelter under fallen logs or 

boulders, and female wolverines give birth to their 

kits in snow-dens.

Neither the current nor historical range of 

wolverines in the lower 48 States was well known 

before the work of these scientists. This was a 

problem because some groups had petitioned

for the wolverine to be listed as an endangered 

species. One of the reasons the petitions were 

denied was because no one was certain where 

wolverines occurred in the United States. The 

scientists in this study, therefore, wanted to 

accurately map the wolverines’ range over time 

and evaluate how climate change might be 

affecting their range.
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The Natural Inquirer • Number 14

Findings

The completed maps showed that the range 

of wolverines shrunk over time, as illustrated by 

wolverine records from historical to current times 

(figures 3a, 3b, and 3c).

Figures 3a, 3b and 3c. The historical, recent, 

and current distribution of wolverines in the 

northern mountains of the Western United 

States. Forest Service image.

Reflection Section

b	 Why do you think the scientists

divided the years into three

different time periods?

b	 How do you think warmer temperatures

might affect wolverines? (Hint: look

back at the Introduction section to see

where wolverines typically give birth.)

Number Crunches

b	 What is the total number of years that the

scientists obtained information about

wolverines?

cover from recent years. The scientists added all 

this information to the maps to see how particular 

climatic conditions or spring snow cover compared 

with the wolverine records.
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Climate Change Edition, http://www.naturalinquirer.org

It was also evident that wolverines depend on 

particular habitat conditions for survival (figures 

4a and 4b).

This study was the first time anyone 

accurately assessed the range of wolverines over 

time. The scientists found that wolverines live 

in areas of the United States where snowpacks 

remain through the spring period. This is the time 

when wolverines make their dens. The scientists 

also found that most wolverine sightings were 

in alpine meadows and conifer forests. Alpine 

meadows are found high in the mountains (figure 

5). Conifer forests are areas with trees that have 

cones and that typically do not lose their leaves in 

the fall or winter (figure 6).

Figures 4a and 4b. Wolverine distribution and the 

location of alpine areas and conifer forests. What 

do you notice about where the wolverines live?

Figure 5. Alpine areas have plants that are 

low to the ground so they can live in the cold 

temperatures.

Figure 6. Some types of conifer forests are 

found in Earth’s cooler regions. 
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The Natural Inquirer • Number 14

Reflection Section

b	 In your own words, summarize

what the scientists found. 

b Do you think the findings support the

idea that the wolverine’s habitat may

be in danger? Why or why not?

Reflection Section

b	 Why would the wolverine’s

reproduction be affected? (Hint:

Think about why wolverines need

spring snow cover.)

b	 Based on what you have learned from

this article, do you think it is possible

that the wolverine may need to be

listed as an endangered species?

Why or why not?

Discussion

Wolverines have already experienced habitat 

losses. Discovering that wolverines live near areas 

that have spring snow cover is important. It is 

important because as the climate changes and 

becomes warmer, the snow in these areas will 

melt earlier in the year. As the climate in these 

areas warms, the range of suitable wolverine 

habitat will change. In addition, the wolverine’s 

reproduction may be affected. The scientists 

believe that more research needs to be done to 

fully understand the potential impact of climate 

change on wolverine populations.

Glossary

accurate (a kyə rət): Free from error.

archived (är kīvd): Collected or filed.

data (dā tə): Factual information used as a basis 

for reasoning, discussion, or calculation.

echidna (i kid nə): A type of egg-laying mammal 

that is also known as a spiny anteater.

enraged (en rājd): Angered.

geographic range (jē ə gra fik rānj): The 

area defined by the location of the farthest 

populations of a species.

extinct (ik stiŋ (k)t): No longer living.

herbivorous ((h)ər biv rəs): Feeding on plants.

marsupial (mär sü pē əl): A pouched mammal.

monotreme (mä nə trēm): Any of the order of 

egg-laying mammals.

observation (äb sər vā shən): Watching carefully 

and making note of details to help arrive at a 

judgment.

petition (pə ti shən): To make a request.

reliable (ri lī ə bəl): Dependable.

species (spē shēz): Groups of organisms that 

resemble one another in appearance, behavior, 

chemical processes, and genetic structure.

terrestrial (təs t(r)ē əl): Of or relating to land as 

opposed to air or water.

Accented syllables are in bold. Marks are from 

the Merriam-Webster Pronunciation Guide.
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Climate Change Edition, http://www.naturalinquirer.org

FACTivity

Time Needed

1.5 class periods

Materials needed per 

student group:

• Animal field guides that include range 

maps, such as bird, reptile, amphibian, 

or mammal guides and other resources 

with wildlife information.

• Two blank maps of the United States.

(See page 27, “Moving on Up,” for a 

blank map.)

• Two pieces of blank white 

8 1⁄2 x 11 paper.

• Markers.

The question students will answer in this 

FACTivity is: What is the range of an animal? 

Process:

In the first class period:

Choose an animal to study that lives in the 

United States. This animal may be selected 

from one of the field guides. Using the field 

guide and other sources, find the following 

information about the animal:

• What is the animal’s habitat? When you 

find out about the areas it lives, mark 

those areas on one of the blank maps.

Label this map “Where [animal species 

name] Currently Lives.”

• What does the animal eat?

• Does the animal have predators? 

If so, what are they?

• What is the average size of the animal?

• What does the animal look like?

• What is the climate where the 

animal lives?

• What are three adaptations the 

animal has so that it can live successfully in its habitat?

Use this information and any other 

interesting facts to create an Animal Fact File.

The Animal Fact File should be displayed on 

two pieces of 8.5- by 11-inch paper.

In a short paragraph, answer the question 

posed at the beginning of this FACTivity.

In the second class period:

One of your blank U.S. maps should already 

be filled out with the animal’s current range.

You will use the other map to make a 

prediction about how you think the animal’s 

range will move as the climate changes.

Think about what you read in the wolverine 

article to help you make this map. Label this 

map “Predicted Future Range of [animal 

species].” Once all of the groups have 

created an Animal Fact File and completed 

the two maps, the files and maps can be 

compiled into a class book.

Extension

If students have read and done the 

FACTivity from “Moving On Up” in this 

edition of the Natural Inquirer, they may 

compare their animal range maps with 

the tree range maps.

If you are a trained Project 

WILD educator, you may 

use the activity “Shrinking 

Habitat” on page 310. 
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The Natural Inquirer • Number 14

Additional Web 

Resources

National Geographic Wolverine Information and 

Pictures

http://animals.nationalgeographic.com/animals/mammals 

/wolverine.html

University of Michigan’s Animal Diversity Web: 

Wolverine Information

http://animaldiversity.ummz.umich.edu/site/accounts/

information/Gulo_gulo.html

National Science 

Education Standards

Standards addressed in this article include:

Science as Inquiry: 

 Abilities To Do Scientific Inquiry,

 Understandings About Scientific Inquiry

Life Science:

 Regulation and Behavior,

 Populations and Ecosystems,

 Diversity and Adaptation of Organisms,

 Reproduction and Heredity

Earth Science:

 Structure of Earth System

Science and Technology: 

 Understandings About Science and Technology

Science in Personal and Social Perspectives:

 Science and Technology in Society,

 Natural Hazards

History and Nature of Science: 

 Science as a Human Endeavor,

 Nature of Science

Adapted from Aubry, K.B.; McKelvey, K S.; and Copeland, J.P. (2007). 

Distribution and broadscale habitat relations of the wolverine in the 

contiguous United States. Journal of Wildlife Management. 71(7): 2147–2158. 

http://www.treesearch.fs.fed.us/pubs/28925.

What You Can Do:

Turn it off! Using less energy means 

producing less carbon dioxide. Some 

examples of things you can turn off 

when you are not using them are lights 

around your house, water when you are 

brushing your teeth, and your computer 

or television. You can also save energy by 

turning down your thermostat and using 

cold water when you wash your clothes.
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Climate Change Edition, http://www.naturalinquirer.org

Climate Change 

Word Search
71

The Natural Inquirer • Number 14

spread can seeds ways many in the trees of

everyone a almost in community lives

 story about tree the tree tell a rings

familiar you GPS a are probably with

sunlight life survive to Earth depends all on on

affect things many temperature stream’s a

steps knowledge in advances usually scientific small

low areas are plants the ground to alpine have that

have already losses wolverines experienced habitat

grows layer it tree a as new growth trunk on a adds its of

time over refers climate to change the Earth’s change in climate

beams ICESat surface light of GLAS as Earth to orbits Earth’s sends

understand the used trees by old scientists past them to the clues provided help

forests provide most tropical animals worldwide plants habitats the of diverse rain some for and

Word Scramble

Unscramble the words to create a sentence from this edition of the Natural Inquirer. 

Word Scramble Answers

The seeds of trees can spread in many ways.

Almost everyone lives in a community.

Tree rings tell a story about the tree.

You are probably familiar with a GPS.

All life on Earth depends on sunlight to survive.

Many things affect a stream’s temperature.

Scientific knowledge usually advances in small steps.

Alpine areas have plants that are low to the ground.

Wolverines have already experienced habitat losses.

As a tree grows, it adds a layer of new growth on its trunk.

Climate change refers to the change in Earth’s climate over time.

As ICESat orbits Earth, GLAS sends beams of light to Earth’s surface.

The scientists used clues provided by old trees to help them understand the past.

Tropical rain forests provide some of the most diverse habitats for 

plants and animals worldwide.
72

Climate Change Edition, http://www.naturalinquirer.org

Note to Educators

Meet the Scientists: Introduces students to 

the scientists who did the research. This 

section may be used in a discussion about 

careers in science.

Thinking About Science: Introduces 

something new about the scientific 

process, such as a scientific habit of mind or 

procedures used in scientific studies.

Thinking About the Environment:

Introduces the environmental topic being 

addressed in the research.

Introduction: Introduces the problem or 

question being addressed by the research.

Method: Describes the method used by the 

scientists to collect and analyze their data.

Findings: Describes the results of the analysis.

Discussion: Discusses the findings and places 

them into the context of the original problem 

or question.

Reflection Section: Presents questions aimed at 

stimulating critical thinking about what has been 

read or predicting what might be presented in 

the next section. These are placed at the end of 

each of the main article sections.

Number Crunches: Presents an easy math 

problem related to the research.

Glossary: Defines potentially new scientific or 

other terms to students. The first occurrence 

of a glossary word is bold in the text.

FACTivity: This is a hands-on activity that 

reinforces an aspect of the research.

Citation: Gives the original article citation with 

a Web link to the original article.

The Forest Service’s mission is to sustain 

the health, diversity, and productivity 

of the Nation’s forests and grasslands to meet 

the needs of present and future generations. 

For more than 100 years, our motto has been 

caring for the land and serving people. The 

Forest Service, U.S. Department of Agriculture 

(USDA), recognizes its responsibility to be 

engaged in efforts to connect youth to nature 

and to promote the development of sciencebased conservation education programs and 

materials nationwide. 

The Natural Inquirer is a science education 

resource journal to be used by students in grade 

5 and up. The Natural Inquirer contains articles 

describing environmental and natural resource 

research conducted by Forest Service scientists 

and their cooperators. These are scientific 

journal articles that have been reformatted to 

meet the needs of middle-school students. The 

articles are easy to understand, are aesthetically 

pleasing to the eye, contain glossaries, and 

include hands-on activities. The goal of the 

Natural Inquirer is to stimulate critical reading 

and thinking about scientific inquiry and 

investigation while teaching about ecology, the 

natural environment, and natural resources. In 

this edition of the Natural Inquirer, you will find 

six articles on climate change written in the 

scientific method format. 

The Format of a Natural 

Inquirer Article

Each Natural Inquirer article follows the same 

format. Natural Inquirer articles are written 

directly from a published science article and 

all have been reviewed by the scientists for 

accuracy. Each article contains the following 

sections, which you may introduce to your 

students as they read.
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The Natural Inquirer • Number 14

Science Education 

Standards 

and Evaluations

In the back of the journal, you will find a 

matrix that enables you to identify articles by 

the national science education standards that 

they address. Each article also contains a list 

of the standards addressed. Evaluation forms 

for both educators and students are available 

on our Web site. We welcome any feedback, 

so please visit http://www.naturalinquirer.

org and complete the online evaluation forms. 

In addition, you may contact Dr. Barbara 

McDonald at the address below with any 

comments you have.

If you have any questions or comments, please 

contact:

Dr. Barbara (Babs) McDonald

Forest Service, USDA

320 Green St.

Athens, GA 30602-2044

706.559.4224

bmcdonald@fs.fed.us

(Please put “Educator Feedback” in the subject line)

Educator Resources

Visit the Natural Inquirer Web site at http://

www.naturalinquirer.org. From this site, you 

can order more editions and read and download 

lesson plans, word games, and other resources 

to help you use the Natural Inquirer in your 

classroom. You can also view and download 

a yearlong lesson plan aimed at helping your 

students learn about the scientific process.

Visit the Natural Inquirer Web site at http://

www.naturalinquirer.org.

Lesson Plan

Note: This is a generic lesson plan that can be 

used with any article in this edition or with any 

Natural Inquirer article. This is because each 

Natural Inquirer article follows the same format 

(See Note to educator, page 72). 

If students have not yet been introduced to the 

Natural Inquirer and the written scientific format 

used by scientists, spend 5 minutes on this topic. 

Below is a sample introduction:

Just as you know the general format 

of a book or of a Web site, scientists use 

a particular format when they write up 

their research. This format usually follows 

the process they used when they did their 

study. Because this format is widely used, 

other scientists know what to expect 

when they read a scientific paper. Think 

about the format of a Web site. If you go 

to a new Web site that has the elements 

and format that you expect, you can 

much more easily understand how to 

search the Web site and find what you 

want to know. Scientists are able to do 

the same thing when they read the papers 

of other scientists. 

The Natural Inquirer is a science journal 

that was written at your reading level. It 

was written directly from research papers 

that were written by scientists. Because of 

this, the Natural Inquirer follows the same 

format as the actual scientific paper and 

it includes additional sections to help you 

better understand what you are reading. 

The heart of a scientific paper has four 

sections: Introduction, Methods, Findings, 

and Discussion.
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Climate Change Edition, http://www.naturalinquirer.org

• Introduction: Introduces the 

problem or question the scientists addressed.

• Methods: Presents the method 

used by the scientists to collect 

and analyze their data.

• Findings: Presents the results of 

the research.

• Discussion: Places the findings into 

the context of the original problem 

or question. 

The extra sections of a Natural Inquirer

article:

• Meet the Scientists: This section 

introduces the scientists whose 

research is presented. 

• Thinking About Science: This 

section provides one big idea, 

addressed in the article, about the 

nature of scientific inquiry.

• Thinking About the Environment: 

This section provides background 

information that introduces the topic 

studied by the scientists.

• Reflection Sections: These 

are questions placed after the 

Introduction, Methods, Findings, 

and Discussion sections to help you 

think about what you have read.

• Number Crunches: These are easy 

math problems that provide greater 

understanding about the research. 

• Glossary: This section introduces 

potentially new terms used in 

the article.

• FACTivity: This is a chance to 

become a scientist as you conduct 

an inquiry or activity related to the 

article you read.

Scientific writing is nonfiction. 

Nonfiction is informational or factual. 

Although most nonfiction writing 

does not have a plot, scientific papers 

come somewhat close to having a 

storyline. This is because a scientific 

paper’s format generally follows the 

process used by the scientists to do 

their research. To better understand a 

scientific paper, it is best to read it in the 

order it is presented. You can think of 

a scientific paper as a factual mystery 

that unfolds in the four sections outlined 

previously: Introduction, Methods, 

Findings, and Discussion sections. 

Scientists are like detectives who solve 

scientific mysteries.

Today we are going to read [title of 

the article you have chosen]. To help 

us think about what we are reading, 

we are going to follow a process. 

First, we will all become THIEVES. 

As THIEVES, we will think carefully 

about what we have read, and then 

we will identify our thinking as “Facts, 

Questions, or Responses.”

Give each student or group a copy of the 

THIEVES chart reproduced at the end of this 

lesson plan. You may either write the questions 

below on the board, or give a copy to each 

student or group. Each student should have a 

copy of the Natural Inquirer article. 

Go over the elements of THIEVES. 

Then, with the Natural Inquirer articles and 

their THIEVES chart, students may begin 

reading. Follow each step in THIEVES, which 

are as follows:

Note: Students can do this exercise 

independently or in a small group.
75

The Natural Inquirer • Number 14

• Read the title. Using the THIEVES 

chart, complete the following: 

• What is the title? 

• Based on the title, what do I think I 

will be reading about?

• Does the title express a point of view? 

If so, what is it?

• Read each of the four main 

article headings, beginning with 

“Introduction.” Using the THIEVES 

chart, complete the following:

• What do I think I will find out in the 

Introduction section?

• What do I think I will find out in the 

Methods section?

• What do I think I will find out in the 

Findings section?

• What do I think I will find out in the 

Discussion secction?

Introductory sections:

• Read Thinking About Science. 

• Using the THIEVES chart, complete 

the “Facts, Questions, Responses” 

chart for that section.

• Read Thinking About the Environment. 

• Using the THIEVES chart, complete 

the “Facts, Questions, Responses” 

chart for that section.

• Based on these introductory sections, 

what do I think the article will be 

about?

• Under each of the four headings, read 

every paragraph. (This is the heart of 

the scientific article.)

• If you find a bolded word that you do 

not know, go to the step labeled “V,” 

for vocabulary.

• If you come to a visual (photograph, 

map, chart, graph, or drawing), go to 

the step labeled “V2” for visuals.

• After reading each paragraph, complete 

the “Facts, Questions, Responses” 

chart 

for that section. 

• Write a sentence or two summarizing 

each of the four sections.

• Review the Vocabulary (Glossary).

• Identify words that you do not know. 

• Sound out words that you do not know 

how to pronounce.

• Make sure you understand every word.

• Look at the visual.

• Write the visual’s number (such as 

figure 1, chart 1, etc.)

• What can I learn from the visual?

• How do the captions help me to 

understand each visual?

• At the end of each section, read the 

Reflection Questions. Think about 

(or discuss, if you are in a group) your 

answers to these questions.

• What do the questions ask?

• What do I learn from the questions?

• What do I learn from answering the 

questions?

Summary and Section 1

• Reread the Discussion section, which 

serves as a summary. Review your 

“Facts, Questions, and Responses” to 

that section.

• Reread the Introduction. Review your 

“Facts, Questions, and Responses” to 

that section.

• What have I learned about the scientific 

process from reading this article?

• What have I learned about the natural 

environment from reading this article? 

The Elements of THIEVES: 

Title, Headings, Introductory sections, Every paragraph, Visuals and Vocabulary, End of 

section questions, Summary and Section 1.

T

H

I

E

V

V2

E

S
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Reading Thieves
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The Natural Inquirer • Number 14

THIEVES was adapted from “Read Write Think,” http://www.readwritethink.org/lesson_

images/lesson112/elements.pdf

“Facts, Questions, and Responses” was taken from www.readinglady.com
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Climate Change Edition, http://www.naturalinquirer.org

Reflection Section Answer Guide

It’s a Small World

Introduction

• What is the question the scientists were 

trying to answer? How did climate and the 

three oscillations affect the timing and location 

of wildfires in the Western United States in the 

past, and how might this change as the global 

climate changes?

• Do you think there were written 

records about fire or sea surface 

temperature patterns such as ENSO, 

PDO, and AMO hundreds of years ago? 

Why or why not? Students should logically 

conclude that there were no written records of 

large-scale sea surface patterns hundreds of 

years ago because people were not aware of 

these patterns at that time and therefore did 

not keep a written record of them.

Methods

• Why do scientists share their data 

with other scientists? What is one 

advantage of sharing data? There is no 

reason to collect information that has already 

been collected. Sharing data saves time and 

money and when data are shared, a better 

understanding often is the result. There may 

be many other explanations that students may 

give. Students should be able to support their 

explanations with logical reasoning.

• Think about how the scientists gathered 

information about the past using tree 

rings. What are other natural resources 

that contain information about the 

climate of the past? Glaciers, rocks, coral, 

lake sediments that contain charcoal from past 

fires, pollen from plants, and soil cross-sections 

are examples of resources that can give clues 

about climate and major events that occurred 

in the past.

Findings

• In your own words, explain how trees 

that lived many years ago have helped 

scientists to understand what may 

happen in the future. Students should 

recall that tree rings and fire scars were 

used to identify how climate and sea surface 

temperature patterns affected wildfire in the 

past. This enables scientists to predict what 

might happen to wildfire in the future given 

predictions of future climate and sea surface 

temperature changes. 

• How might global climate change affect 

the sea surface temperatures? There 

is no right or wrong answer to this question 

because we do not know what will happen. 

If the changing global climate results in rising 

temperatures as predicted, the ocean’s surface 

water temperatures may also rise. The cooler 

phase may not be as cool as in the past and the 

warmer phase may be warmer than in the past. 

Students should reflect on this question but 

realize that we do not have an absolute answer.

Discussion

• Now you understand that sea surface 

temperature patterns and wildfires 

appear to be connected. What are 

other natural processes that might be 

connected to each other? There are many 

different answers for students to think about. A 

student’s answer may be accepted if he or she 

can support the answer with evidence. Some of 

the choices could be glaciers and ocean salinity, 

rainfall in the mountains and ocean nutrients, 

salmon migration bringing deep-ocean nutrients 

to mountain streams, etc.

• Do you think the Western United States 

might have more frequent wildfires in 

the future? Why or why not? This is an 
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The Natural Inquirer • Number 14

individual question, that each student may 

answer uniquely. Students should back up their 

answer with logic. A student’s answer to this 

question depends in large part on whether or 

not he or she believes that the global climate is 

changing and that climate change might affect 

sea surface temperatures and the occurrence of 

wildfires, as described in this research.

Moving on Up

Introduction

• What questions were the scientists 

trying to answer? How might the habitat of 

eastern trees change in the future as the climate 

changes? How might different tree species move 

in response to a changing climate? 

• Do you think a changing habitat may 

also affect the animals that live in the 

Eastern United States? Why or why 

not? Students will have to answer this using 

logic. They should, however, realize that as an 

area’s habitat changes, the animal species that 

live there will also change.

Methods

• Why did the scientists consider what 

may happen if people burn less fossil 

fuels in the future? People are becoming 

more aware of the impacts of burning fossil 

fuels and have begun to use less. It is important 

to understand whether conservation of fossil 

fuels may actually make a difference in the 

future habitat of trees.

• What is one advantage of using maps 

to show research results? Maps can show 

a lot of information quickly. They also easily 

compare the two possible future conditions. 

Maps show where something is happening or 

change is occurring. Students may come up 

with more advantages.

Findings

• If the preferred habitat of sugar maple 

trees moves farther into Canada, what 

possible impact might this have on U.S. 

businesses that sell the sweet product of 

maple trees? If there are fewer sugar maple 

trees to produce maple syrup in the United 

States, the U.S. businesses that produce and 

sell maple syrup may have to change to a new 

product, close down, or buy raw syrup from 

Canadian businesses. 

• Why will the preferred habitats of 

most tree species move in a northerly 

direction? Students should realize that, as 

the average temperature rises across all areas, 

average temperatures will also be “moving” in a 

northerly direction.

Discussion

• The scientists considered what might 

happen if people burned less fossil 

fuels in the future. If people burn even 

less fossil fuels in the future than the 

scientists considered, how might the 

predicted movement of eastern tree 

species change? Students will have to 

use logic (and may need help), but should 

understand that if people burn a lot less fossil 

fuels in the future, the climate may not change 

as much as the scientists have predicted. If this 

is the case, the trees and forests may not move 

as far north as predicted.

• What is one way people might respond 

to this knowledge of changing forest 

communities? If people know in advance 

how forest communities will change, they can 

better plan for those changes. For example, if in 

the future there may be fewer maple trees in the 

United States to make maple syrup, companies 

that make maple syrup might plan to switch 

to another product. If it is predicted that the 

preferred habitat of some pine trees will expand, 

this might create opportunities for companies in 

the wood products industry. If people know that 
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Climate Change Edition, http://www.naturalinquirer.org

the habitat of a particular tree species is changing, 

they can be better prepared to lose that species 

and welcome new tree species to their area. 

The GLAS is Half Full

Introduction

• What questions were the scientists 

trying to answer? Can information 

gathered by satellites be used to identify the 

age of tropical rain forests and to estimate the 

increase in the amount of biomass in growing 

rain forests? Can this information be used to 

estimate the amount of biomass held by old 

rain forests? Is this information as good as the 

information that would be available by studying 

the forests in person? 

• How do you think using information 

gathered by satellites could be more 

efficient than collecting information 

in person? Satellites can gather information 

about large areas of land from around the 

world. Many of the satellites are already in orbit 

collecting data. If those data can be used to help 

scientists understand forests, then using satellite 

data can be more cost effective than trying to 

study all of the forests in person. This is because 

it would cost a lot of money and take a lot of 

time and many people to study all of the world’s 

forests in person, if it were even possible to do so.

Methods

• Why did the scientists study an area 

that had already been studied by other 

scientists working within the forest? 

The scientists wanted to know if data from 

satellites could be used to accurately estimate 

the amount of biomass contained in forests. The 

only way to do this was to collect data from 

satellites, and then compare it with reliable 

information collected by scientists working 

within the forests, where the calculations were 

known to be accurate.

• Do you think the information collected 

by the satellites is exact or an estimate? 

Why or why not? Students will have 

to reason this for themselves. They should, 

however, conclude that information collected by 

the satellites is an estimate. 

Findings

• Think about your own achievement of 

accuracy on a test. Is an 88-percent 

accuracy rate acceptable? Consider 

that the satellites collect a lot more 

data from all across the planet than 

scientists could collect by visiting forests 

in person. Do you think an accuracy 

rate of 88 percent is acceptable? Why 

or why not? Students should realize that 

some accuracy must be sacrificed for data 

collection happening from orbit. They should 

also realize that an 88-percent accuracy rate is 

quite high, considering that using this method, 

data can be collected for forests all over the 

world. It is much better to have an accuracy 

rate of 88 percent for forests worldwide, than 

to have a 100-percent accuracy rate for just 

a small portion of the world’s forests. To help 

students understand, this might be compared 

with getting 100 percent of a two-question 

test correct, compared with 88 percent of a 

100-question test correct. Which of these is the 

better measure of knowledge? 

• Based on the results of this research, 

would you say that data collected by 

satellites may one day be used to help 

estimate the amount of carbon being 

held by the world’s forests? Why or why 

not? Students should understand that the 

methods used in this research, if they can be 

applied to forests worldwide, would provide the 

kind of information that scientists could use to 

more accurately estimate the amount of carbon 

being held by forests world-wide. You may have 

them read the last sentence in “Thinking About 

the Environment,” if they need a hint.
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The Natural Inquirer • Number 14

Discussion

• The scientists did not claim that their 

methods could be used to study all 

forests. Why do you think they did not 

make this claim? This research dealt only 

with tropical rain forests in the Rhondônia area 

of Brazil. Until the scientists have a chance to 

study other types of forests, they will only report 

specifically what they have found. 

• From a climate change perspective, why 

is it important to understand how fast 

the amount of biomass increases in young 

tropical rain forests? Tropical rain forests have 

a large amount of biomass, and therefore they hold 

a large amount of carbon. Understanding how fast 

young tropical rain forests gain biomass helps us to 

understand how effectively these forests can help 

hold some carbon on Earth, instead of having it go 

into the atmosphere.

Back To the Future

Introduction

• What was the question the scientists 

were trying to answer? What was the 

climate like during the time the dead trees were 

alive on Whitewing Mountain and San Joaquin 

Ridge, California?

• Think of an example of something that 

happened to you in the past that helped 

you understand something in the future 

better. For example, last week you did 

not study for your science quiz and 

failed, so this week you studied. Each 

student may uniquely answer this question. 

Students should use reason and logic to support 

their answer.

• Why did the existence of the dead trees 

above the tree line indicate that the 

climate might have been different when 

the trees were alive? Because the tree line 

is the line above which trees cannot survive. 

Evidence of trees above this line indicates that 

the climate must have been warmer in the past.

Methods

• Why did the scientists only map the 

deadwood above the tree line? They 

were interested in discovering something about 

the past climate of the area in which trees can no 

longer grow, but in which trees grew in the past.

• How did technology help the scientists 

in this study? The scientists were able to use 

GPS to map the deadwood. 

Findings

• The scientists measured the change 

in temperature in Celsius. Why did 

they use Celsius to measure and report 

temperature rather than Fahrenheit? 

The metric system is the system scientists 

use to report their information. Celsius is the 

temperature measurement in the metric system. 

• Why are these findings important to our 

understanding of the future? If climate 

change predictions are correct, the future is 

likely to be warmer. This study revealed that 

the area above the current tree line was once 

warmer and drier. If the area above the current 

tree line is warmer and drier in the future, it 

may once again be habitat for the tree species 

that lived in the area in 1350.

Discussion

• Based on this article and your own 

experience, why do you think it is 

important to study the past? Things that 

happened in the past may be able to help us 

predict what might happen in the future.

• Why do you think scientists try to 

predict things that will happen in the 

future? For example, why do you think 

scientists want to know what trees 

may be alive in the future if the climate 

becomes warmer? If we have a good idea 

of what might happen in the future, we can 

better plan for it. Each student may answer this 

question uniquely, and each answer should be 

backed up with logic and reasoning. 
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Climate Change Edition, http://www.naturalinquirer.org

Did They Make the 

Gradient?

Introduction

• What do you think determines the 

shape of a stream? A stream’s shape is 

more than its direction of flow. Students should 

consider a stream’s width and depth as things 

that help determine its shape. They should also 

think about the type of bedrock through which 

the streamflows. Some streams, for example, 

are relatively straight because they cut through 

softer rocks. Other streams have a lot of bends 

and turns because they must flow around rocks, 

or their soils are easily eroded. Brainstorm with 

your students to come up with factors that 

determine a stream’s shape. 

• Do you think that a rise in the average 

air temperature would cause a rise in 

a stream’s water temperature? Why or 

why not? Students should reason that, if air 

temperature affects a stream’s water temperature, 

then a rise in average air temperature over time 

would result in an average rise in a stream’s water 

temperature over time.

Methods

• Why do you think the scientists studied 

streams that were near each other but 

had a different geology? The geology, 

or underlying rock type, helps determine the 

stream’s shape. To compare different stream 

shapes, the scientists needed to find streams 

with different underlying geology (or structure). 

To be comparable, however, it was best to 

find streams that would otherwise be close 

geographically, so that air temperature, solar 

radiation, and other weather data would be 

similar for all streams. This question gives 

students an opportunity to understand the 

concept of controlling as many variables as 

possible in a study.

• Why was it important to study streams 

with similar day-to-day weather? 

Because the scientists were interested in how 

a stream’s shape affects water temperature, 

the weather data needed to be as similar as 

possible for all streams. This would remove 

one of the sources of variation from the study. 

This question gives you another opportunity to 

discuss with your students how scientists control 

independent variables so that the dependent 

variable(s) can be more accurately studied.

• Look at figure 6. Why did the scientists 

not compare the two variables 

represented by the lower right rectangle? 

Because at nighttime, there would be no shade 

without sunlight. 

• Which other variable in this figure would 

not be compared with nighttime water 

temperatures? Solar radiation.

Findings

• Why do you think the most shaded 

streams had the lowest daytime 

summer temperatures? Students should 

realize that shade provides some protection 

from the Sun’s warmth. 

• Why do you think that stream 

temperatures in a future warmer 

climate might rise more in the winter 

than in the summer? (Hint: think about 

what is different about many of the 

trees along streambanks in the summer 

and winter.) Because trees provide more 

shade in the summer, they will moderate the 

rise in stream temperatures. They will do this 

no matter the air temperature. This does not 

mean that stream temperatures will not rise 

in a warmer climate. It means, however, that 

trees can help reduce the effect of a warmer 

climate on stream temperatures, especially in 

the summer when they have leaves.

Discussion

• Think back to the first question in the first 

Reflection Section. Did you or your class 

consider the gradient of the stream as one 

way to describe its shape? Do you agree 

that the gradient of a stream is part of its 
83

The Natural Inquirer • Number 14

shape? Why or why not? Students will have 

to answer this question themselves. They should, 

however, explore why they did or did not think of 

the gradient as part of a stream’s shape. If they 

have difficulty with this, challenge them to think of 

whether the steepness (or gradient) of a mountain 

is a part of its shape. How is a mountain’s shape 

similar to and different from a stream’s shape?

• Most States have laws that protect 

streams and rivers. These laws prohibit 

the removal of trees and other plants 

within a certain number of feet from the 

water’s edge. Do you think this is a good 

thing? Why or why not? Students will have 

to answer based on their own assessment. Most 

students should come to the conclusion that laws 

meant to protect streams are good for a number 

of reasons. You may challenge your students to 

think of other ways streamside vegetation protects 

streams. These include, for example, the reduction 

of soil erosion into streams, the provision of 

wildlife habitat, the protection of the scenery along 

streams, and the protection from pollutants that 

might wash into the streams and waterways. 

There’s Snow Place 

Like Home

Introduction

• What questions were the scientists 

trying to answer? What is the geographic 

range of wolverines over time? How might 

climate change affect the geographic range 

of wolverines? 

• What are some other animals that 

burrow or make dens for their homes? 

There are many different animals that 

burrow or make dens. Some examples include 

groundhogs, ants, hamsters, foxes, ferrets, 

chipmunks, badgers, moles, prarie dogs, pikas, 

rabbits, shrews, and sand dollars.

Methods

• Why do you think the scientists divided 

the years into three different time 

periods? The scientists divided the time 

because it was easier to discuss and analyze 

their findings based on smaller time periods. 

Scientists often place large amounts of 

information into categories so that it can be 

more easily analyzed and understood.

• How do you think warmer temperatures 

might affect wolverines? (Hint: look 

back at the Introduction section to see 

where wolverines typically give birth.) 

Warmer temperatures may cause the snow 

to melt earlier. If the snow melts earlier, the 

wolverine’s denning habitat won’t be as good or 

may not be available at all.

Findings

• In your own words, summarize what 

the scientists found. The scientists found 

that spring snow cover, alpine areas, and 

conifer forests were important to the range of 

wolverines. They also found that by the 1950s, 

wolverine range had begun to shrink. 

• Do you think the findings support the idea 

that the wolverine’s habitat may be in 

danger? Why or why not? This is an individual 

question. Each student may answer this question 

uniquely. Students should be able to support their 

answers with examples from the article.

Discussion

• Why would the wolverine’s reproduction 

be affected? (Hint: think about why 

wolverines need spring snow cover.) The 

wolverines make their dens in the snow. They 

reproduce and raise their kits in these dens. 

• Based on what you have learned from 

this article, do you think it is possible 

that the wolverine may need to be listed 

as an endangered species? Each student 

may uniquely answer this question. Students 

should be able to support their answers with 

examples from the article. 
It’s a Small World

Moving on UpThe GLAS is Half FullBack to the FutureDid They Make the Gradient?There’s Snow Place Like Home

Science As Inquiry

 Abilities Necessary To Do Scientific Inquiry X X X X X

 Understandings About Scientific Inquiry X X X X X X

Life Science

 Regulation & Behavior X X

 Populations & Ecosystems X X X X

 Diversity & Adaptations of Organisms X X X X

 Reproduction & Heredity X

Earth Science

 Structure of Earth System X X X X

Science and Technology

 Understandings About Science and Technology X X X X X

Science in Personal & Social Perspectives

 Risks & Benefits X

 Science & Technology in Society X X X X

 Natural Hazards X X

History & Nature of Science

 Science As a Human Endeavor X X X X X X

 Nature of Science X X X X X X

Which National Science 

Education Standards 

Can Be Addressed by 

These Articles?

84

Climate Change Edition, http://www.naturalinquirer.org
85

The Natural Inquirer • Number 14

What Is the USDA 

Forest Service?

The Forest Service is a 

part of the United States 

Department of Agriculture 

(USDA). It is made up of 

thousands of people who 

care for the Nation’s forest land. The 

USDA Forest Service manages over 

150 national forests and almost 20 

national grasslands. These are large 

areas of trees, streams, and grasslands. 

National forests are similar in some 

ways to national parks. Both are public 

lands, meaning that they are owned by 

the public and managed for the public’s 

use and benefit. Both national forests 

and national parks provide clean water, 

homes for the animals that live in the 

wild, and places for people to do fun 

things in the outdoors. National forests 

also provide resources for people to use, 

such as trees for lumber, minerals, and 

plants used for medicines. Some people 

in the Forest Service are scientists 

whose work is presented in the journal. 

Forest Service scientists work to solve 

problems and provide new information 

about natural resources so that we can 

make sure our natural environment is 

healthy, now and into the future.

What Is the 

Cradle of Forestry 

Interpretive 

Association?

The Cradle 

of Forestry 

Interpretive 

Association 

is a 501(c)3 

nonprofit organization based out 

of Brevard, North Carolina. The 

Interpretive Association strives to 

help people better understand ecology 

through recreation and education 

opportunities. Their projects include:

• Campground and recreation 

area management.

• Educational programs 

and services, including the 

Natural Inquirer.

• Sales of forest-related gifts 

and educational materials.

• Workshops, newsletters, 

and publications.

• Partnership with the Forest 

Service to provide programming 

at the Cradle of Forestry 

Historic Site.

The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, 

disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, 

reprisal, or because all or part of an individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) 

Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact 

USDA’s TARGET Center at (202) 720–2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 

Independence Avenue, S.W., Washington, D.C. 20250–9410, or call (800) 795–3272 (voice) or (202) 720–6382 (TDD). USDA is an equal opportunity 

provider and employer.
FS 955

Winter 2011

United States 

Department 

of Agriculture

Forest Service

Additional Web 

Resources

Natural Inquirer

http://www.natural 

inquirer.org

Investi-gator

http://www.science 

investigator.org

Forest Service Conservation Education

http://www.fs.fed.

us/kids/ (Click on 

Conservation 

Education)

Forest Service 

Climate Change 

Resource Center

http://www.fs.fed.

us/ccrc/

Climate Change 

Atlas

http://www.nrs.

fs.fed.us/atlas/

EPA’s Climate 

Change Web site

http://www.epa.

gov/climatechange/ 

wycd/school.html

Athens-Clarke County, Georgia Leisure Services Department, 

Memorial Park Day Camp, Counselors Michael James, 

Sanjay Rema, and Katie McMichael

Oconee County, Georgia Parks and Recreation Department, 

Teen Extreme Program, Kelsey Tate, Assistant Youth Programs 

Coordinator and David Martin, Counselor

EPA’s Climate 

Change Kids’ site

http://www.epa.gov/ 

climatechange/kids/

Climate Change 

Calculator

http://www.ameri 

canforests.org/ 

resources/ccc/ 

Forests and Climate 

Change Toolbox 

(USAID)

http://www.cifor.cgiar.

org/fctoolbox/