Sample of ESS Protocol
you will perform an Earth system science analysis. Then, you will
make predictions, based on the results of the ESS analysis, concerning
the policy debate about whether to let naturally caused fires in
national parks burn to their natural conclusion.
steps below will help you to accomplish your tasks.
1 List what is known.
Step 2 List what is needed.
Step 3 Gather information to complete
an ESS analysis. ( Event to Sphere, Sphere to Sphere)
Step 4 Present your findings.
1: List What Is Known
two columns below illustrate the parallel jobs to be completed in
Step 1. You do not need to conduct any research to do this step.
Use your current knowledge and information from the scenario to
fill in the lines provided.
In the space
provided in the first column, list what you know about Yellowstone
National Park fires.
Then look at
the Earth System Diagram in the second column. Notice how the arrows
go to and from the event and spheres. These arrows indicate that
the cause and effect relationships go both from the event to the
spheres and from the spheres to the event (
). While thinking about these relationships, list your ideas about
how the event--wildland fires--could possibly impact the four spheres
that make up the Yellowstone National Park ecosystem.
knowledge about Yellowstone National Park fires.
- In 1988,
there were many wildland fires burning in Yellowstone National
- The firefighters
were unable to control the fires and the fires blazed all summer
- It was very
hot and dry that summer. The region was suffering from a severe
- A large portion
of the Park was destroyed.
caused some of the fires, human carelessness with lit matches
and campfires caused some of the fires, and people may have set
some of the fires.
knowledge of Earth system science regarding wildland fires.
- Fires need
fuel to burn. Dead branches and pine needles on the ground provide
fuel for wildland fires.
- Fires need
a source of heat to ignite. People provide heat to ignite wildland
fires by being careless with lit matches or campfires. Some people
even set wildland fires on purpose.
- Flames from
wildland fires kill plants and animals.
- After wildland
fires, populations of some animals decrease as a result of the
loss of their food sources (plants or other animals).
- Animals that
can escape fast-moving wildland fires may be forced to re-locate
- The flames
of wildland fires scorch rock surfaces.
- The intense
heat from wildland fires causes some rocks to break apart into
- As mentioned
above, fires need heat to ignite. Lightning contains a lot of
heat energy. Lightning strikes ignite some wildland fires.
- Fire needs
oxygen to burn. This is evident when you use a snuffer to put
out a candle: a snuffer cuts off the oxygen supply to the flame
and the flame goes out.
fires produce smoke that contains ash and gaseous pollutants such
as carbon dioxide (CO2). Wind carries the ash and gases away from
suffered from record low humidity and an extended drought during
1988. A lack of water caused the soil and vegetation to dry out.
A lack of moisture in the soil and vegetation may have provided
dry matter to ignite wildland fires.
2: List What Is Needed.
that you have an idea of what you DO know about Yellowstone National
Park and the impacts of the event on the spheres and the spheres
on the event, you need to think about what you DO NOT know. Below,
you will ask questions that will guide the research that may take
place on the Internet, in the library, or with other sources.
In the first
column, list your questions about Yellowstone National Park fires.
Ask questions in the second column to direct the research you will
conduct in Step 3. These questions should help
you to focus your research on finding information to complete the
ESS analysis of the impacts that wildland fires could have on the
four spheres that make up the Yellowstone National Park ecosystem.
your questions regarding Yellowstone National Park fires.
- How much
land was burned?
- Were all
the animals killed?
- How long
did the fires burn?
- Has any fire
season in Yellowstone National Park before or since 1988 been
- Have any
inhabitants of the biosphere recovered from the fires?
- Were any
inhabitants of the biosphere harmed to the point that they have
not recovered from the fires?
- Were any
homes or campers destroyed during the fires?
- Why was this
fire so big?
- Do fires
often occur in this region?
your questions regarding the impacts that wildland fires could have
on the four spheres that make up the Yellowstone National Park ecosystem.
- Are some
inhabitants of the biosphere adapted to survive in fire-prone
- Do some inhabitants
of the biosphere benefit from wildland fires? If yes, then how?
- Are terrestrial
(land) plants and animals the only inhabitants of the biosphere
affected by wildland fires?
- What happens
to the nutrient content of the lithosphere when it is burned?
- What happens
to the pH of the lithosphere when it is burned?
- Will plants
grow on soil that has been burned?
- Will there
be more mudslides after a wildland fire since there is no longer
vegetation holding the soil in place?
- What happens
to the pH of streams and lakes after a wildland fire?
- How is the
pH of precipitation affected by the smoke in the air from a wildland
3: Gather information to complete an ESS analysis.
Part I: Using
the answers from your research, list any additional cause and effect
relationships you found for the event and the spheres. These relationships
should build on or be different from the ones you listed in Step
1. The answers you find should explain the possible causes and effects
wildland fires could have on the spheres that comprise the Yellowstone
National Park ecosystem. Keep track of where you locate
information. You may need to look it up again when you do Step
- Some plant
species have adapted to living in fire-prone areas and surviving
small fires. For example, the Douglas fir that lives in Yellowstone
National Park survives wildland fires because it has a thick bark.
The bark protects it from fires with low heat intensity. The Douglas
fir is also self-pruning. That means it drops its dead branches
to the forest floor. This decreases the chance of a fire climbing
up the tree using dead branches as a "ladder".
- Some tree
species must go through a fire before their seeds can germinate.
One such tree is the lodgepole pine. This tree makes up roughly
80% of Yellowstone National Park's forest. It produces two types
of cones. One is an open cone that spreads its seeds as soon as
it is mature. The other is a closed cone that is sealed by a resin.
Closed cones must be exposed to the intense heat of a fire before
they can spread their seeds. The heat from the fire cracks open
the cones and allows them to release their seeds. In this way
the lodgepole pine re-seeds the burned forest floor.
- Many people
camp in the Yellowstone area and live near the park. These people
are in danger of losing all their possessions--even their lives--in
wildland fires. For example, during the 1988 fires, residents
had to be evacuated from Cooke City and Silver Gate because the
flames were dangerously close to their homes. Only a few backcountry
employee cabins were destroyed.
- Dry, dead
plant material is fuel for wildland fires. The build up of fuel
material is referred to as fuel loading. The greater the fuel
load in a forest, the greater the chance of a wildland fire igniting
and rapidly spreading throughout the ecosystem. This is what happened
in Yellowstone in 1988. Controlled burning or salvage timbering
removes the excess fuel. The removal of excess fuel is referred
to as "fuel management." Fuel management decreases the chance
of wildland fires becoming large, uncontrollable wildfires.
fires burn in a patchwork pattern. The result is a more diverse
landscape with some open areas among forested areas. The diverse
landscape provides many types of habitats for many types of plants
and animals. The result is increased biodiversity.
very few large animals are killed during wildland fires. For example,
the Yellowstone Park fires of 1988 only killed approximately five
bison, 243 elk, one black bear, two moose and four deer.
- The initial
destruction of vegetation by wildland fires decreases food supplies
for herbivores. Populations of these animals may begin to decrease
as a result of starvation or emigration. Herbivores are prey for
carnivores. If herbivore populations decrease, then the food supply
for carnivores decreases. Populations of carnivores may then decrease
as a result of starvation or emigration.
- When substances
are burned, such as trees in wildland fires, they leave behind
ash. This is the fine, grayish material seen in the bottom of
campfire pits or charcoal grills after their fires have gone out.
fires have always occurred in the northwestern Rockies. Between
1972 and 1987, 235 "prescribed" fires were allowed to burn in
Yellowstone National Park. Those fires burned 33,000 acres of
- The wildland
fires of 1988 were the largest series of fires in the northern
Rockies in the last 50 years. They burned 1.5 million acres--800,000
in Yellowstone Park and 700,000 outside the Park.
fires burn humus, the nutrient-rich organic matter in the topsoil.
The organic matter rapidly breaks down and releases its mineral
- Intense heat
plays a key role in cycling rock through the lithosphere. Heat
from wildland fires can break apart rocks. The small rock fragments
can be cemented together over time to form sedimentary rock.
- Ash particles
(see Wildland Fires Event
Biosphere) are basic, meaning they have a high pH. Ashes produced
by wildland fires increase the pH of soil.
- Fire needs
oxygen to burn. Wildland fires warm the air above them. The warm
air rises and creates "updrafts." Updrafts "fan" wildland fires
by adding oxygen to them. This causes the fires to become more
intense and spread.
fires start and spread most when the air is hot, dry, and windy
(see above and Wildland Fires Event
Hydrosphere). At night, air temperatures are lower, humidity is
higher, and winds are slower. For these reasons, wildland fires
tend to "lay down" at night. This means they stop blazing and
spreading and just slowly smolder.
- The air above
wildland fires is full of burning embers that are carried by the
wind. These burning embers fly through the air and land on unburned
vegetation. This is how wildland fires spread rapidly. It is also
why burn patterns are patchwork instead of solid.
- Heat from
wildland fires may further remove moisture from the air and soil
through the process of evaporation. During this process, heat
transforms liquid water into a gas that rises into the atmosphere.
By drying surrounding vegetation, the fire actually creates more
burnable fuel in its path. This allows the fire to continue to
can naturally extinguish wildland fires. On September 11, 1988,
two inches of wet snow covered a large portion of Yellowstone
National Park. The snow put out some of the flames and prevented
the fire from spreading.
- During wildland
fires, fire-fighting materials can pollute lakes and streams.
For example, fire retardant material was accidentally dropped
into Little Firehole River during the 1988 Yellowstone fires.
the answers from your research, list the cause and effect relationships
that occur between and among the spheres. Note: Begin thinking
about how these relationships may in turn affect the Yellowstone
National Park ecosystem.
- Smoke contains
ash particles, as well as many toxic gases. The thick, black toxic
smoke makes seeing and breathing very difficult during wildland
fires. This makes it hard to escape the deadly flames. People
and animals can also die of suffocation or smoke inhalation during
strikes may come in contact with vegetation. The heat from the
lightning can ignite the fuel (vegetation) and cause a fire to
- Dry vegetation
Hydrosphere) is more flammable than wet vegetation. This means
the drier the vegetation, the more likely it is to catch fire
- Old trees
in dense forests block sunlight from reaching the ground below
their canopy. Young seedlings cannot grow because they lack the
sunlight they need to photosynthesize. During wildland fires,
trees are removed from portions of a forest (see Wildland Fires
Biosphere). The canopy is opened up. Sunlight is able to shine
through to seedlings in the open patches of forest floor. New
vegetation is able to grow.
- Ash particles
in the air can fall to the ground miles away from the wildland
fire. Large deposits of ash may eventually cement together to
form sedimentary rock.
can block winds and keep them from fanning the fires (see Wildland
- Ash from
burning plant and animal material can be washed from the atmosphere
by precipitation. This ash may be carried to nearby streams.
- Ash particles
in the air are condensation centers. This means water vapor can
condense on the particles to form water droplets. Groups of water
droplets form clouds. When the water droplets become too heavy
for the air to hold, they fall from the sky as precipitation.
Wildland fires increase the amount of condensation centers (ash)
in the air. Therefore they may increase the amount of precipitation
in surrounding areas.
- Hot, dry
air increases the rate of evaporation of water from plants and
soil. The heat causes the water to transform from a liquid state
to a vapor. The vapor is released to the air.
- Smoke from
fires contains carbon dioxide (CO2). Carbon dioxide
reacts with water in the atmosphere to form carbonic acid, H2CO3.
The chemical equation for this reaction is H2O + CO2
H+ + HCO3-
Carbonic acid has a low pH. It decreases the pH of precipitation.
The result is more acidic precipitation.
- Ash particles
in the water can clog the gills of fish and other aquatic organisms
and choke them.
- A lack of
rain can cause plants to dry out. Little water in plants makes
it easier for them to catch fire.
of waterways with fire-fighting materials (see Wildland Fires
Hydrosphere) can lead to the death of aquatic organisms. For example,
cutthroat trout were killed when fire retardant material was accidentally
dropped into Little Firehole River during the 1988 Yellowstone
concentrations of dissolved oxygen in waterways (see Hydrosphere
Lithosphere) can result in the suffocation of aquatic organisms.
- Plant roots
and leaves absorb water. Without vegetation to take up water from
precipitation, more water will flow directly into streams. This
can lead to increased flooding.
- Acidic precipitation
Hydrosphere) can decrease the ability of plants to take up nutrients.
It can also "burn" the leaves of some sensitive plants. The result
is an overall decrease in plant health and growth.
- Plant roots
hold soil in place. A decrease in vegetation can lead to increased
erodibility of soil. An extreme example of such erosion is the
mudslide activity in the northwestern United States. This region
has suffered the loss of trees due to forest fires and heavy logging.
Without vegetation to hold them in place, entire hillsides slide
downhill when they become saturated with rain.
- The burning
of the nutrient-rich topsoil increases the nutrient content of
the soil (see Wildland Fires Event
Lithosphere). This fertilization aids in rapid re-vegetation of
- An increase
in soil pH (see Wildland Fires Event
Lithosphere) results in increased activity of nitrogen-fixing
bacteria. I read this in an ecology textbook. Nitrogen-fixing
soil bacteria convert nitrogen in the soil to a form that is usable
precipitation (see Atmosphere
Hydrosphere)--as well as water used to put out the fire--may wash
away loose soil (see Biosphere
erodibility of soil (see Biosphere
Lithosphere) may lead to more sediment washing into waterways
(i.e. muddier water). High sediment loads in waterways causes
the temperature of the water to increase. As water temperature
increases, the amount of oxygen in the water decreases.
- Acidic precipitation
Hydrosphere) dissolves calcium carbonate (limestone) and weathers,
or breaks down, this type of rock.
block the movement of air (see Atmosphere
Lithosphere). Air currents are forced to move upward when they
reach mountains. As they move upward, air currents cool. The water
vapor in the air condenses until it becomes so heavy the air can
no longer carry it. The air looses most of its water as precipitation
by the time the air reaches the mountaintop. Therefore air that
comes down the other side of the mountain is very dry. This is
why there are often deserts on the leeward side (side away from
the wind) of mountains.
4: Present your findings
a report or presentation of your team's recommendations about the
prescribed burning policy in Yellowstone National Park based on
your ESS analysis.
based on ESS Analysis:
1988, wildland fires raged through the northern Rockies from May
through September. The fires burned 1.5 million acres of the region.
Eight hundred thousand acres of the burned land was in Yellowstone
National Park. Because of huge economical losses created by these
fires, the effectiveness of Yellowstone's fuel management policy
is being debated. This policy allows naturally caused fires to burn
to their natural end. The purpose of fuel management is to control
the amount of fuel (dry, dead vegetation) building up in the Park.
The goal of this policy is to reduce fire control costs and damages.
Some government officials do not believe Yellowstone Park's fuel
management policy meets these goals.
A group of government
agencies has contacted our team of environmental biologists to resolve
this policy debate. They have asked us to perform an Earth system
science (ESS) analysis of the effects of fire on the Yellowstone
ecosystem. The government agencies would like us to recommend whether
or not naturally caused fires in national parks should be allowed
to burn to their natural conclusion.
have always been common, natural occurrences in the northwestern
Rockies of the United States. Flames spread across that area long
before European settlers arrived there. When the Yellowstone National
Park was established, park officials thought wildland fires destroyed
the Park's ecosystem. People began to fight the fires. Fighting
the fires is very expensive, though. Besides, the occasional natural
fire removed dry, dead vegetation from the Park. Without these fires,
fuel would build up. A large, uncontrollable fire could ignite.
For these reasons, many national parks, including Yellowstone, established
fuel management policy. Park services personnel began to allow naturally
caused fires to burn to their natural end.
above, the goals of Yellowstone National Park's fuel management
policy are to reduce fire control costs and damages. Under this
policy, some naturally caused wildland fires are allowed to burn
without human interference. To be allowed to burn, these "prescribed"
fires must meet certain criteria. The fires cannot endanger people,
property, or resource values. They cannot cross the wilderness boundary.
The weather conditions and forecast must be favorable (not too dry
or too windy) so there is little danger of the fire growing or spreading
out of control. There must also be enough resources available to
put out the fires if the other criteria can no longer be met.
our team performed an ESS analysis of wildland fires in Yellowstone.
The results of this analysis show that the Park's fuel management
policy does accomplish its goals of reducing fire control costs
and damages. The policy does this by limiting the occurrence of
wildfires. Wildfires are wildland fires that become large and out
of control. Wildfires create the most damage and cost the most to
fight. Wildland fires become wildfires when there is a seemingly
endless supply of the three ingredients needed for a fire to occur.
These three ingredients are oxygen (A > E), heat (A > E
and B > E), and fuel (B > E). Nature can provide all three
of these ingredients. Oxygen and heat are controlled primarily by
weather patterns. Park officials have no way of controlling the
high winds that provide oxygen or the lightning that provides heat.
The only thing park officials can control is the amount of fuel
available in the area. By allowing small fires to burn dry, dead
vegetation, park services keeps the fuel from building up.
above, however, park officials cannot control the weather. The 1988
fire season was hot, dry, and windy. The hot, dry air (atmosphere)
caused water (hydrosphere) to evaporate from living vegetation (biosphere)
as well as dead vegetation. The plant material became so dry that
the entire forest became fuel. Lightning struck the fuel and winds
fanned the flames with oxygen. The fires burned and spread out of
control (E). The causal chain of this set of reactions leading up
to a wildland fire event can be represented as A > H > B
> E. The fire control costs and damages of these fires were very high.
However, the important thing to keep in mind is it was an abnormally
hot, dry, windy fire season. The park officials could not control
these factors. All they could do was try to reduce the amount of
fuel in the region through prescribed burning.
Our ESS analysis
of this situation also revealed many environmental benefits of wildland
fires. First of all, wildland fires revive forests. After 50 to
100 years, forests (biosphere) become mature. They consist of only
a few types of trees. The canopy of the large, mature trees closes
in. No light from the atmosphere is able to reach the lithosphere
below the canopy. New seedlings are unable to grow without sunlight.
Also, the existing trees have taken up most of the nutrients from
the lithosphere. New seedlings cannot grow without nutrients.
(E) allow seedlings to receive the sunlight and nutrients they require
to grow. Wildland fires do this by thinning out forests. They remove
some of the older trees (B) and open patches in the canopy. Sunlight
(A) is able to shine through these patches and reach new seedlings
(B). New vegetation is able to grow. The causal chain of this set
of reactions is E > B > A > B. When fire (E) burns existing
trees (B), their nutrients are released back to the soil (L). The
nutrients become available to new seedlings (B). This, too, allows
new vegetation to grow. The causal chain for this set of reactions
is E > B > L > B.
fires (E) create open patches on the forest floor (L), they allow
different types of new vegetation (B) to grow. Each type of vegetation
provides a different type of habitat. The presence of different
types of habitat allows many types of organisms to live in the area.
The result is increased biodiversity. This is another way in which
wildland fires benefit the biosphere. The causal chain of this set
of reactions is E > B > L > B.
Based on our
ESS analysis of the effects of wildland fires on the Yellowstone
ecosystem, we recommend that the park services continue to follow
their current fuel management policy. Controlling the amount of
fuel available is the only way that park officials can control the
spread of wildfires. Allowing small, natural fires to burn to their
natural conclusion is a good way to remove fuel. In addition, fire
is very beneficial to wildland ecosystems. Fire naturally revives
forests and makes them healthier.