Download 1 ` ENSO Jigsaw [Key Science Knowledge Module] 1 Activity

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2 - 3 days
ENSO Jigsaw
[Key Science Knowledge Module]
Activity Overview
This module is the most important learning
module in terms of the physical science
aspects associated with the El Niño /
Southern Oscillation (ENSO) and climate
forecasting. Teachers have flexibility in
how the material is covered in this learning
module to meet the objectives of the Climate
Unit.
Learning Module 3 is designed using the
jigsaw approach to learning. It will take at
least two days to complete the jigsaw.
Another option is to skip the ENSO jigsaw
and have the students complete only the
“Becoming an Expert” material. A third
option is to skip the “Becoming an Expert
Section” and go straight to students filling
out the “ENSO Jigsaw.” These alternatives
will shorten the time requirements. Finally,
the teacher can use their own lessons and
textbook concerning ENSO. Students need
to understand how ENSO affects climate
(precipitation) to fully appreciate Learning
Module 4.
Student Learning Objectives
(Depends on material and activities
covered in completing the learning
module)
The student
1. Learns scientific aspects of ENSO.
2. Learns how ENSO affects climate
variability in the U.S. and worldwide.
3. Works cooperatively in groups.
Teaching Summary
Step 1
Journal / Bell Work- if appropriate
Step 2
ENSO Jigsaw
There is flexibility in this step as discussed
in the activity overview and the three
replacement steps, Steps 3-5.
Step 3 - Replaces Step Two
Becoming an Expert - only
Step 4 - Replaces Step Two
ENSO Jigsaw – only
Step 5 - Replaces Step Two
Teacher’s own material
Step 6
Homework / Assessment
Materials Needed
For The Teacher
Becoming an Expert Handouts
ENSO Jigsaw Handouts
Divide the students into “expert groups.”
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Step 2 – ENSO Jigsaw
For the Student
Becoming an Expert Handouts – for each
group member – better if printed in color
ENSO Jigsaw Handouts – for each student –
if printed in color
Crossword puzzle – for each student or
student group
For teachers not familiar with the jigsaw
approach to learning, a brief overview of
this method is provided in Appendix A of
this Learning Module. ENSO Jigsaw is
composed of two parts the “Becoming an
Expert on ___” reading material and the
“ENSO Jigsaw Worksheet.”
Teacher Activity – Jigsaw Approach
National Standards
Module provides
address science,
geography national
Guide for specific
grades 5-8.
integrated approach to
math, reading and
standards. See Teacher
standards addressed for
Texas Essential Knowledge and Skills
(TEKS)
Module provides integrated approach to
address science, math, reading, and
geography standards. See Teacher Guide
for specific standards addressed for grades
sixth, seventh, and eighth.
The jigsaw approach divides the class into
groups. Each group goes through a selfdirected learning activity to become
“experts” on a particular topic. Groups are
then reassembled with one student from
each expert group is now present in each
new group.
Each student teaches the
material they had learned in their expert
group to the members of the new group.
The teacher may want to mention to the
students that the material will make more
sense once the jigsaw is completed, that is
once all the individual components are
brought together.
Day One
Teaching Suggestions
Step 1 - Journal / Bell Work
The goal is to review the ENSO Introduction
from Learning Module 2. To achieve this
goal, ask one or more of the following
questions and have students either write in
their journals or field answer from students.
Suggested questions are:
What is ENSO?
What do you know about ENSO?
What is one fact you learned yesterday
from out discussion of ENSO?
1. Divide the students into eight “expert
groups.” This will allow you to run two
jigsaws (four groups each) with the
information provided. One expert group
is necessary for each ENSO topic. Each
student in an expert group is given the
appropriate “Becoming an Expert on
___” reading material and worksheet.
The four “Becoming on Expert on ___”
reading material and worksheets are (for
eight expert groups, assign two groups
per topic):
Trade winds / Southern Oscillation /
Walker Circulation – this is the longest
topic, the teacher may consider
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assigning this topic to their best
students.
El Niño – Warm Phase,
La Niña – Cold Phase, and
Impact of ENSO on Climate Variability.
variability worldwide. To complete this
section, all the expert reading material is
necessary. Suggested use of this section
is for enrichment or advanced classes.
5. The group completes the ENSO Jigsaw
Worksheet using the four experts to
teach the material.
2. Each expert group completes their
worksheet on “Becoming an Expert on
___”. Students should compare answers
within their groups and come to a
consensus as to what is the correct
answer.
6. Each group shares their completed
ENSO Jigsaw Worksheet with the class
– if time allows.
3. Expert groups should check their
worksheet with the answer key to ensure
correct answers for completing the
jigsaw.
Step 3 - Replaces Step 2 – Becoming an
Expert – only
Days Two and Three
4. New student groups are formed with
each student being an expert on a
different topic. The experts teach their
particular topic to the other students in
the reformed group using the “Becoming
an Expert on ___” worksheet.
In
teaching the topic, the students answer
the questions associated with each topic
in the ENSO Jigsaw worksheet.
The three sections on the “ENSO Jigsaw
Worksheet” are
7. Check answer key to make sure each
answer is correct.
Using this option, each student completes all
four “Becoming an Expert on ___”
worksheets. The ENSO Jigsaw Worksheet
is not completed.
Teacher Activity
Questions contained in the “Becoming an
Expert on ___” are completed using either
direct instruction, individually by each
student, or in student groups. Each student
is given a copy of the appropriate reading
materials for “Becoming an Expert on ___.”
If groups are used, the material can be
shared between groups.
This sharing
reduces the amount of material that must be
handed out to students.
ENSO Jigsaw – Pacific Ocean Aspects,
ENSO Jigsaw – U.S. Climate Variability
Aspects, and
ENSO Jigsaw – Worldwide Climate
Variability Aspects – Optional.
The first two sections are required. The
third optional section looks at climate
Step 4 - Replaces Step 2 – ENSO Jigsaw –
only
Using this option, each student completes
the ENSO Jigsaw Worksheet.
The
“Becoming an Expert on ___” worksheets
are not completed.
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Teacher Activity
Questions contained in the ENSO Jigsaw
Worksheet are completed using either direct
instruction, individually by each student, or
in student groups. Each student is given a
copy of the appropriate reading materials on
ENSO topics. Depending on the method
used, reading material is given to the
individual student or a group of students. If
groups are used, the material can be shared
between groups. This sharing reduces the
amount of material that must be handed out
to students.
Step 5 – Replaces Step 2 -Teacher’s Own
Material
The teacher can chose to use their textbook
or own ENSO science concept materials.
Step 6 - Assessment / Homework
Assessment Options
1. ENSO Jigsaw Worksheet and / or
becoming an expert questions.
2. Journal reflection: what information did
you learn today?
3. Have students answer either verbally or
written the following question, “How do
we use the information we have learned
to help Joe make a decision?”
and be ready to teach this information to
a new group on day two.
2. Complete the “Other Affects of ENSO”
reading and worksheet. Students could
complete the entire worksheet or
different students could complete the
different sections and report to the class.
This worksheet can be used as
homework / enrichment.
Enrichment Options
1. Have students research ENSO by
visiting one or more of the NOAA
websites related to ENSO and then write
a short paragraph on what they have
learned from visiting the sites.
2. Have the students complete the ENSO
Jigsaw – Worldwide Climate Variability
Aspects – Optional worksheet; the
students will need all the expert reading
material.
3. Have the students complete the ENSO
crossword puzzle; the students will need
all the expert reading material.
4. Have the students provide a more in
depth report on the effect of ENSO on
climate variability for a particular area of
the U.S.
5. Have the students complete the “Other
Affects of ENSO” reading and
worksheet.
Homework Options
1. Day One - have students study their
becoming expert questions, answers, and
reading material on their ENSO topic.
Students should reread their handouts
Struggling Learners
1. If using the jigsaw approach, have the
experts work in pairs instead of
5
individuals. Pair struggling learners
with a peer tutor.
2. If completing the “ENSO Jigsaw”
individually, provide a set of reading
that highlights the most important
aspects.
3. In completing the “ENSO Jigsaw,” use
multiple-choice questions instead of the
open ended set of questions.
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Becoming an Expert on Trade Winds,
Southern Oscillation, and the Walker Circulation
To become an expert on trade winds, the
Southern Oscillation, and the Walker
Circulation, read the following information
and complete the questions. Your teacher
may require you to read other sources of
information.
Trade Winds
The ocean and atmosphere are related or
interact. This relationship is called coupled
by scientists. Trade winds and the Walker
Circulation in the tropical Pacific Ocean
play important roles in understanding
ENSO.
and westward in the tropical Pacific Ocean.
The trade winds are part of the coupled
ocean-atmosphere interaction in the tropical
Pacific. The trade winds determine the
water temperature at the same time the water
temperature determines the trade winds.
This is the coupling of the ocean and
atmosphere. They are linked to the point
that they cannot be separated. The trade
winds are so named as early sailing ships
used the winds to sail from South America
westward. The strength of the winds is such
that the Pacific Ocean level is approximately
half a meter higher in the western Pacific
(Indonesian) than it is in the eastern Pacific
(Peru, South America).
Southern Oscillation
Equator
Differences in sea surface temperatures
between the east and west equatorial Pacific
Ocean cause the trade winds. The sun heats
the sea surface to a higher temperature near
the equator than the rest of the world.
Heating the sea surface temperature causes
the air to rise from the surface. The rising
air is replaced by air inflows from the cooler
subtropics. This is seen in the following
trade wind patterns for the winds at the
equator.
As shown in the figure, the northern and
southern trade winds turn in different
directions.
By turning in different
directions, the trade-wind belts are made.
The trade winds blow towards the equator
Coupled with the sea surface
temperature is air pressure. The Southern
Oscillation is a seesaw of air pressure near
the equator between the eastern and western
Pacific Ocean. This oscillation is measured
as changes in the differences in air pressure
between Tahiti, French Polynesia and
Darwin, Australia. In general, lower air
pressure is found where the air is rising and
higher pressure where the air is sinking.
The Southern Oscillation is a measure of the
strength of the trade winds, which flow from
regions of high to low pressure.
Walker Circulation
The Walker Circulation associated with
the trade winds is the vertical and horizontal
circulation of air associated with the trade
winds.
The
following
figure
(http://www.pmel.noaa.gov/tao/elnino/ninohome.html#) shows the coupling of sea
surface temperatures and the Walker
circulation.
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Under normal conditions, the
winds blowing westward cause a large
pool of warm water in the western
Pacific Ocean. Air rises over this
warm pool. Rising air leaves the lower
atmosphere and airflows in to fill the
gap. The air filling the gap causes the
winds to blow towards the warm
water. The winds blowing in to fill the
gap are the trade winds.
The warm pool of water releases
large amounts of heat and moisture
into the atmosphere.
Sea surface
temperatures in the warm pool are up
to 6 degrees Celsius warmer than in
the cooler pools. This warm pool is an
Western Pacific
Eastern Pacific
important force in determining world
climate by altering the jet streams (storm
tracks) that control weather in the temperateby phytoplankton, which support high fish
zones. Changes in the position of the warm
production. With a shallower thermocline,
pool in the Pacific Ocean can affect much of
nutrients necessary for life in the ocean are
the world's weather.
closer to the surface making for more
abundant plant and animal life. Having the
One other important aspect shown in the
thermocline moving close to the surface is
figure is the position of the thermocline.
called upwelling.
Wherever upwelling
The thermocline is the boundary between
occurs there is more abundant life than other
the colder deep water and warmer upper
areas of the ocean where upwelling does not
water layer. By blowing westward, the trade
occur.
winds force the thermocline to be deep in
the western Pacific Ocean and shallow in the
These normal conditions provide the
eastern Pacific Ocean. In the west, the
starting point to understand La Niña and El
thermocline is up to 150 meters deep. In the
Niño events.
east, the thermocline is around 30 meters
deep.
This difference in thermocline
location has an affect on the biological make
up of the Pacific Ocean. Colder deep water
is usually richer in life-supporting nutrients
than the warmer surface water. These
nutrients support high primary production
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Questions Concerning Trade Winds/Southern Oscillation/Walker Circulation
1. The ocean and atmosphere are related. Scientist call this relationship
Coupled
2. Where are the sea surface temperatures the greatest?
Near the Equator
3. What happens to the air when the sea surface temperature heats up?
The air rises
4. What causes the trade winds?
Air filling the gap left by rising air which causes winds to blow towards warm water.
5. How do the northern and southern trade winds different?
They turn in different directions
6. How are the trade winds and the ocean coupled?
Trade winds determine the water temperature at the same time water temperature determines
the trade winds
7. What is the southern oscillation?
A see saw of air pressure near the equator between the eastern and western Pacific Ocean.
8. What is air normally doing where the air pressure is low?
The air is rising
9. What is air normally doing where the air pressure is high?
The air is sinking
10. What is the Southern Oscillation a measure of?
The strength of the trade winds, which flow to regions of high to low pressure
11. What is the Walker Circulation?
The vertical and horizontal circulation of air associated with trade winds
12. Why is the warm pool so important?
It alters the jet streams (storm tracks) that control weather around the world.
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13. How does the thermocline affect the biological make up of the Pacific Ocean?
With a shallower thermocline nutrients necessary for life in the ocean are closer to the
surface making for more abundant plant and animal life.
14. What is upwelling?
Having a thermocline moving close to the surface.
15. Understand the figure in the readings concerning the Pacific Ocean during normal ENSO
conditions.
After completing the questions above you are now an expert on trade winds, Southern
Oscillation, and Walker Circulation. Your job is to share your knowledge with new partners
tomorrow. You should study your information and answers for homework and be ready to
explain these processes to your classmates. Be sure you explain the key terms.
10
Becoming an Expert on El Niño – Warm Phase
To become an expert on El Niño read the
following information and complete the
questions. Your teacher may require you to
read other sources of information.
Recall from Learning Module 2, the
three most common phases associated with
ENSO are El Niño, La Niña, and neutral. El
Niño is also referred to as the warm phase
and La Niña the cold phase. The popular
story of how El Niño got its name is as
follows. El Niño originally referred to the
warming of the Pacific Ocean off the coast
of the South American country of Peru that
appears around Christmas time. In Spanish,
El Niño means small boy or child. If the
word is capitalized, El Niño refers to Jesus
as an infant. So, the anticipation of the
celebration of the birth of Christ and the
warming of the Pacific Ocean became
known as El Niño. Exact origin and date of
the use of the word El Niño is not known.
Be prepared to give the story of the naming
of El Niño in the jigsaw groups.
when averaged over three consecutive
months in the Niño 3.4 region. El Niño is
sometimes referred to as the warm phase
because of the warmer sea surface
temperatures in the eastern Pacific. The
eastward movement of the warm pool causes
the thermocline to move down in the eastern
Pacific Ocean and to become shallower in
the western Pacific. The thermocline is the
boundary between the colder deep water and
warmer upper water layer.
Opposite air pressure conditions than
those that occur in an El Niño event are
generally associated with La Niña events.
Lower than normal air pressure in the
eastern Pacific and higher air than normal
air pressure in the western Pacific are
associated with El Niño. Smaller pressure
difference in the Southern Oscillation is
associated with weaker than normal trade
winds during an El Niño. These changes are
shown
in
the
figure
(http://www.pmel.noaa.gov/tao/elnino/ninohome.html#).
Referring to El Niño as the warm phase
is simply in reference to the warming
of the Pacific off the South American
coast.
Scientists do not know what
causes El Niño phases to develop.
They do know, however, the affects
of the phase. The following are
changes from normal conditions.
The trade wind experts will provide
you with information on normal
conditions. During El Niño phases,
the trade winds weaken. The warm
pool of water in the equatorial
Pacific moves eastward. El Niño is
defined by sea surface temperatures
that are warmer than or equal to 0.5
degrees Celsius higher than normal
Western Pacific
Eastern Pacific
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These changes in the coupled oceanatmosphere system can lead to changes in
climate variability around the world. These
changes in climate conditions are associated
with the changes in location of the warm
pool. The warm pool is a major source of
heat and moisture to the atmosphere.
Changes in the thermocline cause changes in
upwelling in the Pacific Ocean. Biological
aspects of the ocean change with the
changes in upwelling. With the change in
upwelling, there is less biological life near
the ocean surface in the eastern Pacific
Ocean than under neutral conditions.
The following figure shows some the
global affect of El Niño’s on climate
variability. El Niño’s affect is stronger
during the northern hemisphere winter
season, December – February than during
the summer season. This does not mean for
the gulf region of the U.S. all El Niño years
will have higher precipitation levels during
the winter season, but there is an increased
probability of higher precipitation. During
an El Niño, the western Pacific tends to
experience warmer and dryer climate
conditions. The southern U.S. tends to
experience wetter and cooler climate
conditions.
Western Canada and
Northwestern U.S. experience warmer than
normal temperatures.
Other worldwide
affects of El Niño are shown in the figure.
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Questions on El Niño – Warm Phase
1. El Niño phase is also referred to as the ______warm________ phase.
2. Do scientists know what causes El Niño to develop?
Yes
No
3. What happens to the trade winds during an El Niño phase?
They weaken
4. What happens to the southern oscillation pressure difference during an El Niño phase?
The pressure difference is small or decreases
5. What happens to the pool of warm water during an El Niño phase?
It moves eastward
6. What is the definition of an El Niño phase?
El Niño is characterized by warmer sea surface temperatures change from normal in the Niño
3.4 region than greater than or equal to 0.5 degrees Celsius averaged over three consecutive months.
7. What happens to the thermocline during an El Niño phase?
It becomes shallower in the western Pacific and deeper in the eastern Pacific
8. What happens to the air pressure during an El Niño phase?
In the eastern Pacific there is lower than normal air pressure and in the western Pacific there
is higher than normal air pressure
9. Analyze the maps of the global effects of El Niño. How could this possibly affect Joe
Soccer’s decision? Remember Joe Soccer lives in the Southern U.S.
Wet and cool conditions are expected during El Niño phase – may want to play in the indoor
league
10. Are the effects of El Niño on precipitation the same worldwide?
Yes
No
11. Are the effects of El Niño on temperature the same worldwide?
Yes
No
12. Provide one example where the effects differ or are the same.
Students may pick from the many examples in the reading.
13. Understand the figure in the readings concerning the Pacific Ocean during El Niño
conditions.
After completing the questions above you are an expert on El Niño. Your job is to explain this
event to your new partners tomorrow. You should study your information and answers for
homework and be ready to explain this process to your classmates tomorrow.
13
Becoming an Expert on La Niña – Cold Phase
To become an expert on La Niña read
the following information and complete the
questions. Your teacher may require you to
read other sources of information.
Recall from Learning Module 2, the
three most common phases
associated with ENSO are El Niño,
La Niña, and neutral. El Niño is
also referred to as the warm phase
and La Niña the cold phase. In
Spanish, La Niña refers to the girl
child. Once you come together in
the jigsaw groups, ask your El
Niño expert how El Niño got its
name.
generally associated with La Niña events.
Air pressure is higher than normal in the
eastern Pacific and lower than normal in the
western Pacific.
This large pressure
difference in the Southern Oscillation is
associated with stronger than normal trade
Scientists do not know what
causes La Niña phases to develop.
They do know, however, the
affects of the phase. The following
are
changes
from
normal
conditions. The trade wind experts
Western Pacific
Eastern Pacific
will provide you with information
winds during a La Niña phase. These
on normal conditions. During La Niña
changes are shown in the figure
phases, the trade winds strengthen. The
(http://www.pmel.noaa.gov/tao/elnino/ninowarm pool of water in the equatorial Pacific
home.html#).
moves farther west. La Niña is sometimes
referred to as the cold phase because of the
These changes in the coupled oceancooler sea surface temperatures in the
atmosphere system can lead to changes in
eastern Pacific. La Niña is defined by sea
climate variability globally. The warm pool
surface temperatures in the Niño 3.4 region
is a major source of heat and moisture to the
that are 0.5 degrees Celsius or cooler than
atmosphere. Changes in the thermocline
normal temperatures when averaged over
cause changes in upwelling in the Pacific
three consecutive months. The westward
Ocean. Biological aspects of the ocean
movement of the warm pool causes the
change with the changes in upwelling. With
thermocline to become shallower in the
additional upwelling, there is more
eastern Pacific Ocean and deeper in the
biological life near the ocean surface in the
western Pacific Ocean. The thermocline is
eastern Pacific Ocean than under neutral
the boundary between the colder deep water
conditions.
and warmer upper water layer.
Opposite air pressure conditions than
those that occur in an El Niño event are
General changes in climate variability
associated with La Niña are shown in the
figure below. La Niña’s affect is stronger
14
during the northern hemisphere winter
season, December – February than during
the summer season. This does not mean for
the gulf region of the U.S. all La Niña years
will have lower than normal precipitation
levels during the winter season, but there is
an increased probability of less rain. During
a La Niña phase, the western Pacific tends to
experience cooler and wetter climate
conditions. The southern U.S. tends to
experience dryer and warmer climate
conditions.
Western Canada and
Northwestern U.S. experience cooler than
normal temperatures.
Other worldwide
affects of La Niña are shown in the figure.
15
Questions on La Niña – Cold Phase
1. La Niña phase is also referred to as the ______cold________ phase.
2. Do scientists know what causes El Niño to develop? Yes
No
3. What happens to the trade winds during a La Niña event?
They strengthen
4. What happens to the southern oscillation pressure difference during a La Niña event?
Pressure difference is large or increased
5. What happens to the warm pool of water during a La Niña phase?
It moves westward
6. What is the definition of a La Niña phase?
La Niña is characterized by cooler sea surface temperatures than normal in the Niño 3.4
region greater than or equal to 0.5 degrees Celsius averaged over three consecutive months.
7. What happens to the thermocline during a La Niña phase?
It becomes deeper in the western Pacific and shallower in the eastern Pacific
8. What happens to the air pressure during a La Niña phase?
In the eastern Pacific there is higher than normal air pressure and in the western Pacific there
is lower than normal air pressure
9. Analyze the maps of the global effects of La Niña. How could this possibly affect Joe
Soccer’s decision? Remember Joe Soccer lives in the Southern U.S.
Dryer and warmer conditions are expected during La Nina phases – may want to play in the
outdoor league
10. Are the effects of La Niña on precipitation the same worldwide?
Yes
No
11. Are the effects of La Niña on temperature the same worldwide?
Yes
No
12. Provide one example where the effects differ or are the same.
Students may pick from the many examples in the reading
11. Understand the figure in the readings concerning the Pacific Ocean during La Niña
conditions.
After completing the questions above you are an expert on La Niña. Your job is to explain this
event to your new partners tomorrow. You should study your information and answers for
homework and be ready to explain this process to your classmates tomorrow.
16
Becoming an Expert on Impact of ENSO on Climate Variability
To become an expert on climate
variability related to ENSO read the
following information and complete the
questions. Your teacher may require you to
read other sources of information.
The coupling of the ocean and
atmosphere laid the foundation for
explaining teleconnections between ENSO
and climate variability in regions outside the
Pacific Ocean. A teleconnection is a
linkage between a physical process in one
region and climate anomalies in other
regions. Teleconnections between ENSO
and climate conditions have been made for
parts of Australia, North and South America,
southern Africa, India, northern Africa, and,
Southeast Asia.
The strength of the
teleconnection depends on the strength of
the ENSO event. The affect of ENSO on
climate variability also depends on the time
of the season. The strongest ENSO impacts
are found close to the equator.
Two important points associated with
ENSO’s affect on climate variability must
be explained. First, the affect of ENSO on
climate variability is a change in the
probability of increase or decrease in
precipitation amounts and temperatures.
Second, no one storm can be attributed to an
ENSO.
Often in the popular media,
nonscientific writers attribute a single storm
to the ENSO event.
For example, a
snowstorm is attributed to a La Niña phase
during the winter.
This is incorrect.
Snowstorms occur every year. Rather, the
ENSO event is associated with an increase
in the probability of higher or lower
precipitation amounts or temperatures.
Pacific / North American Jet stream
Changes
Scientists do not know what causes
ENSO phases to develop. They do know,
however, the affects of the different phases.
Teleconnections partially depend on the
Walker circulation. Shifts in the Walker
Circulation change airflows east and west
over the tropical Pacific. These shifts affect
the jet stream that, in turn, modifies storm
patterns.
Jet streams are a relatively
narrow band of strong winds in the upper
levels of the atmosphere. Jet streams are
usually found approximately 6-9 miles
above the earth's surface. Changes in the jet
stream causes changes in the storm patterns
for North America are illustrated in the
following figure. During an El Niño event,
cooler, wetter weather occurs in the southern
U.S. because the Pacific jet stream tends to
stay on a southern track. This jet stream
pattern brings in storms from the Pacific
Ocean to the southern U.S. The Polar jet
stream is pushed to the east, which is
associated with warmer weather in Northern
U.S. and parts of Canada.
La Niña conditions tend to push the
Pacific jet stream northward.
This is
associated with fewer storms in the southern
U.S. The northern track of the Pacific jet
stream is associated with wetter weather in
northwest U.S. The polar jet stream tends to
be pushed westerly. The western position of
the polar jet stream is associated with cooler
temperatures in the northern U.S. and parts
of Canada.
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18
Questions on ENSO’s Impact on Climate Variability
1. What is a teleconnection?
A linkage between ENSO and climate variability in regions outside the Pacific Ocean.
2. What parts of the world have teleconnections been made between ENSO and climate
conditions?
Australia, North and South America, Southern Africa, India, Northern Africa, and South East
Asia
3. Where are the strongest ENSO impacts found?
Close to the equator
4. Two important points are discussed in the information regarding ENSO’s affect on climate
variability. Explain those two points in your own words.
ENSO can increase or decrease amounts of precipitation, no one storm can be because of an ENSO.
Others
5. Why is a change in the jet stream important in determining climate variability for the U.S.?
A change modifies storm patterns
6. What happens to the Pacific jet stream during an El Niño phase during January to March?
It is persistent and stays on a southern track.
7. What general affect does the change of the jet stream during an El Niño phase have on
climate conditions in the southern U.S. during January to March?
Southern U.S. tends to be wetter and cooler than normal
8. What general affect does the change of the jet stream during an El Niño phase have on
climate conditions in the northern U.S. during the January to March.?
Northern U.S. tends to be dryer and warmer than normal
9. What happens to the Pacific jet stream during a La Niña phase during January to March?
Pushes north and is more variable
19
10. What general affect does the change of the jet stream during a La Niña phase have on climate
conditions in the southern U.S. during January to March?
Southern U.S. tends to be dryer and warmer than normal
11. What general affect does the change of the jet stream during a La Niña phase have on climate
conditions in the northern U.S. during January to March?
Northern U.S. tends to be wetter and cooler than normal
12. Understand the figure in the readings concerning the jet stream and climate variability across
the U.S. Sketch the figure.
El Nino Conditions
La Nina Conditions
After completing the questions above you are an expert on U.S. climate variability associated
with ENSO. Your job is to explain this event to your new partners tomorrow. You should study
your information and answers for homework and be ready to explain this process to your
classmates tomorrow.
20
ENSO Jigsaw Worksheet - Pacific Ocean Aspects
Under the normal conditions provide a definition of the physical aspect, whereas under El Nino and La
Nina note the Pacific Ocean anomaly (difference from normal) for the phase. Be sure you understand the
pictures and are able to sketch them. Hint: conditions are usually opposite between the two conditions.
Anomaly from Normal
Physical Aspect
Definition / Importance
Anomaly from Normal
Moves East
Warm Pool of Water - importance
Important in determining climate
variability
Moves West
Shallower in the west and deeper in
the east
Thermocline
The thermocline is the boundary
between the colder deep water and
warmer upper water layer.
Deeper in the west and shallower in
the east
Weakens
Trade Winds / Walker Circulation
The Walker Circulation associated
with the trade winds is the vertical and
horizontal circulation of air associated
with the trade winds.
Jet Stream
Jet streams are a relatively narrow
band of strong wind in the upper
levels of the atmosphere.
Another Phase Name
No Definition
Southern Oscillation
Strengthens
Stays on a southern track
Warm
Pressure difference is small
Pushes north and are more variable
Cold
Large pressure difference
A see saw of air pressure near the
equator between the eastern and
western Pacific Ocean.
Less upwelling in the eastern Pacific
leads to less plant and animal
production in the eastern Pacific
Upwelling - Biological
The thermocline is close to the surface
is called “upwelling.”
Where
upwelling occurs there is more
abundant life than areas of the ocean
where upwelling does not occur.
More upwelling in eastern Pacific
leads to more plant and animal
production in the eastern Pacific
21
ENSO Jigsaw Worksheet – U.S. Climate Variability Aspects
1. This page pertains to ENSO affects on climate, especially during January to March period.
For the two different phases, mark (a circle would work) with a red pencil the areas of the
U.S. that have warmer than normal temperatures. With a blue pencil, mark areas that have
cooler than normal temperatures. In green, mark the areas that have higher than normal
precipitation. Finally, in brown mark the areas that have lower than normal precipitation.
Draw in the changes in the jet stream between the two phases. Be Neat!
La Nina – Cold Phase
See readings for correct conditions and jet stream.
El Nino – Warm Phase
2. What is a teleconnection?
A linkage between ENSO and climate variability in regions outside the Pacific Ocean.
3. Recall, Joe Soccer lives in Southern U.S. What is the typical anomaly associated with El
Niño phase for precipitation and temperature in Texas?
Rain – wet
Temperature cool
4. What is the typical anomaly associated with La Niña phase for precipitation and temperature
in Texas?
Rain – dry
Temperature warm
5. Do these anomalies always occur as you answered in questions 2 and 3 for El Niña and La
Niña phases?
Yes
No
6. Discuss in your group how Joe might use the above information.
22
ENSO Jigsaw Worksheet – Worldwide Climate Variability Aspects - Optional
This page pertains to ENSO affects on climate. For the two different phases, mark (a circle would work) with a red pencil the areas
that have warmer than normal temperatures. With a blue pencil, mark areas that have cooler than normal temperatures. In green,
mark the areas that have higher than normal precipitation. Finally, in brown mark the areas that have lower than normal precipitation.
On one of the maps, mark the location of the Niño 3.4 region. Be Neat! One may need to refer back to the “Becoming an Expert on
___” reading materials. See reading materials for correct answers.
La Nina – Cold Phase
El Nino – Warm Phase
1. Do these anomalies you colored put in the maps always occur as you answered for El Niña and La Niña phases?
2. Why do you think the anomalies are stronger in the equator region of the world than in the rest of the world?
ENSO is located in the equator region and other phenomen located elsewhere also impact climate
3. Why do you think much of the research into ENSO has originated in Australia?
Australia is one of the countries most impacted by ENSO
Yes
No
23
ENSO Crossword Puzzle - Optional
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Constructed using Crossword Weaver
Across
2
4
5
7
8
11
12
14
Upper level winds that create storm
tracks.
First scientist to rigorous study ENSO
precipitation and temperature over a
period longer than two weeks
El Nino phase is sometimes know as
this because of hotter than normal sea
surface temperatures
Relationship between the ocean and
atmosphere
The boundary between cold deep water
and warmer upper layer of water in an
body of water.
precipitation and temperature over a
period of two weeks or less
Linkage between physical process in
one region and climate variability in
another region.
15
Walker _____ is the vertical and
horizontal movement of the trade
winds, which form a circular pattern
Down
1
3
6
9
10
13
Changes in climate between years is an
example of this
changes from the normal or a base
Imaginary line around the middle of
the world.
____ Oscillation refers to the seesaw
pattern of air pressure between the
western and eastern Pacific Ocean.
____ winds cause the sea level to be
higher in the western Pacific Ocean
La Nina phase is sometimes known as
this because of cooler than normal sea
surface temperatures
24
ENSO Cross Word Puzzle Solution
V
WA L K E R
R
C L I M A T E
A
Q
B
C O U P L
I
A
L
T
T H E
I
R
O
T
A
R
W
Y
D
T E L E C O
J E T S T R E A M
N
O
WA R M
O
E D
L
S
I
R M O C L I N E
U
S
E A T H E R
H
C
N N E C T I O N S
R
L
C I R C U L A T I O N
D
25
Other Effects of ENSO - Optional
There is evidence of ENSO having an effect on the occurrence of forest fires, floods, and
hurricanes, along with impacts on human health. But, what are these effects? As with ENSO,
scientists are still learning about links between climate and other physical, biological, and human
aspects. The following paragraphs provide brief explanations to how ENSO may affect these
different aspects. Answer the following questions after reading the associated paragraphs.
Forest Fires / Floods
As you learned in the science module, ENSO impacts precipitation in various areas of the world.
Changes in precipitation can lead to other changes in the environment. One such change is a
change in the number of wildfires, both brush and forest fires. As you have learned previously,
the different ENSO phases may cause some areas to be drier than normal. Decreased
precipitation may lead to an increase in wildfires. For example, during some El Niño years,
increased number and severity of forest fires have been reported in Indonesia (country northwest
of Australia) and Australia. The most predominant year for forest fires in Indonesia was the El
Nino of 1982 and 1983. The 1997- 1998 year also saw an increased number of forest fires.
These years saw particularly strong El Niño phases. Similarly, increased precipitation associated
with an ENSO phase in a particular area may cause an increase in flooding. But, not all years
see an increase in fires or floods.
1. Why is there a greater risk of increased forest fires during an El Niño year in Australia?
Australia has a higher chance of being dryer than normal
2. During what El Niño season were forest fires most predominant?
1982-1983
3. What country has suffered the most recently from the effects of forest fires associated with
the El Niño phase?
Indonesia
4. Why do some areas see an increased probability of flooding during an El Niño year?
Increased probability of higher precipitation levels
26
Hurricanes
Hurricanes (also known as tropical cyclones or typhoons depending on the area of the world they
occur) need warm ocean water to develop. Hurricanes occur during all ENSO phases. However,
changes in the warm pool of water cause by the different ENSO phase have implications for
location and development of hurricanes. In the western Pacific Ocean, El Niño phases decreases
tropical cyclone activity. This is expected as the warm pool of water moves eastward. Activity
in the central and eastern Pacific increases during El Niño phase. Hurricane activity in the
Atlantic basin is affected by ENSO through changes in the Atlantic atmospheric circulation. El
Niño phases contribute to a decreased numbers of Atlantic tropical storms and hurricanes. La
Niña phases generally have opposite conditions, increased storms in the western Pacific and
Atlantic Oceans and decreased storms in the central and eastern Pacific Ocean.
Bove et al.
(http://www.aoml.noaa.gov/hrd/Landsea/elnino/) give the average number of U.S. Atlantic
hurricanes during El Niño years is 1.04, 1.61 during neutral years, and 2.23 during La Niña.
5. Why does a La Niña event increase the risk for of a hurricane in Australia?
The warm pool has moved closer to Australia, and warm water is needed for hurricanes to
forms.
6. How does an El Niño event affect the number of hurricanes affecting the U.S.? Hint:
consider both Atlantic and Pacific Oceans.
El Niño warms the eastern tropical Pacific Ocean, which aids in the growth of hurricanes in
the eastern Pacific, but it is associated with a lower number of hurricanes in the Atlantic
Ocean.
7. How does a La Niña event affect the number of hurricanes affecting the U.S.? Hint: consider
both Atlantic and Pacific Oceans.
La Niña warms the western tropical Pacific Ocean, which lowers the growth of hurricanes in
the eastern Pacific, but it is associated with a higher number of hurricanes in the Atlantic
Ocean.
8. During an El Niño phase 1.04 hurricanes always hit the U.S. True or false and why?
False. This is the average number and not the number for any given year
27
Human Health
The World Health Association notes a pattern between the different ENSO events and outbreak
of diseases. However, generalizing the relationship between disease outbreaks and ENSO events
is not easy. Local health delivery systems affect the incident of diseases. In addition, local
ecological conditions, along with humidity, timing of precipitation, and temperature changes,
affect the transmission of diseases. To illustrate the complex relationship between ENSO and
diseases consider the case of malaria. Malaria is a mosquito borne disease. In countries that are
normally relatively warm with low precipitation levels (such as countries in southern Africa), an
ENSO phase that increases precipitation may be associated with increased cases of malaria. This
occurs because increased precipitation causes increases in standing water necessary for
mosquitoes to reproduce. More mosquitoes mean a higher chance for disease outbreak.
Increased precipitation leads to increased cases of malaria.
In countries that are normally warm and have high precipitation levels (such as Venezuela,
Columbia, and Sri Lanka), an ENSO phase that decreases precipitation may lead to an outbreak
of malaria. Decreased precipitation may turn normal flowing rivers into stagnant ponds. These
stagnant ponds provide the breeding grounds for the mosquitoes which flowing rivers could not
provide. Here, decreased precipitation leads to increased cases of malaria. In addition to
malaria, researchers have found approximately 21 infectious diseases that may have a
relationship with ENSO. Other diseases that may have a relationship with ENSO events include
Dengue, Australian Encephalitis, Rift Valley Fever, and valley fever. Much more research is
necessary to understand the relationship between health and ENSO events.
http://www.who.int/mediacentre/factsheets/fs192/en/
9. Malaria is transmitted by what insect?
Mosquito
10. Besides ENSO what other factors are important in determining if a disease outbreak occurs.
Local ecological conditions, local health system, local humidity, precipitation and
temperatures.
11. Countries that normally have high precipitation levels may see an increase in malaria during
ENSO phases that bring decreased precipitation. Why?
Decreased precipitation may cause rivers to run slower, thus creating pools that mosquitoes
can live in. Increased mosquitoes mean a better chance for a disease outbreak.
12. Countries that normally have low precipitation levels may see an increase in malaria during
ENSO phases that bring increased precipitation. Why?
Increased precipitation may stagnant pools of water to form that mosquitoes can live in.
Increased mosquitoes mean a better chance for a disease outbreak.
28
13. Optional Question: ENSO impacts other physical and biological phenomenon in addition to
the ones discussed here. Write a short paragraph on other potential ENSO impacts by
conducting web-based research. Suggested topics, but not limited to, are fish production in
the eastern Pacific, western U.S. snow pack, tornados in the U.S., droughts in Australia, and
salmon production in the U.S. and British Columbia.
For additional information see
Forest Fires
http://ess.geology.ufl.edu/usra_esse/ENSO_Impacts.html
http://iri.columbia.edu/climate/ENSO/societal/impact/methods/BasicQuestions.html
Human Health
http://image.thelancet.com/extras/02art5336web.pdf
http://www.who.int/mediacentre/factsheets/fs192/en/
http://www.ispe.arizona.edu/climas/research/vf/background.html
Hurricanes
http://www.aoml.noaa.gov/hrd/Landsea/lanina/
http://www.aoml.noaa.gov/hrd/Landsea/elnino/
http://www.aoml.noaa.gov/hrd/tcfaq/G2.html
Tornados
http://www.spc.noaa.gov/publications/schaefer/el_nino.htm
29
Appendix A
ENSO - Jigsaw Approach
One method of teaching is the jigsaw
approach. In this approach, students are
placed into groups. Each group becomes
the “expert” in a particular topic. After
the groups have completed the expert
materials, new groups are formed with
an expert from each topic in the new
group. An example for three topics is
given in the figure below. Each box
represents a group.
In this setup,
Claudia, Jose, and Fred become experts
on trade winds, Seth, Cindy, and Lebron
become experts on El Niño, and Ivan,
Megan, and LeAnn are the La Niña
experts.
Each expert member then
teaches their topic to students in the new
group. For example, in new group 1,
Claudia would teach trade winds, Seth
El Niño, and Ivan La Niña. New groups
2 and 3 would be similar. In teaching
the material in the new groups, each
student in the class, finishes their ENSO
Jigsaw Worksheet.
Each expert material contains questions
designed to provide the student the
necessary knowledge to help fellow
students complete the ENSO Jigsaw.
The
Jigsaw
worksheet
provides
questions that summarize important
concepts; as such the worksheet provides
a review sheet for testing purposes.
The jigsaw idea can be modified to fit
your textbook.
Trade Winds
Claudia
Jose
Fred
El Niño
Seth
Cindy
Lebron
La Niña
Ivan
Megan
LeAnn
New Group 1
Claudia
Seth
Ivan
New Group 2
Jose
Cindy
Megan
New Group 3
Fred
Lebron
LeAnn