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ENSO Jigsaw
[Key Science Knowledge Module]
Use contents of this packet as you feel appropriate. You are free to copy and use any of the material in
this lesson plan.
Packet Contents
ENSO Jigsaw Components
The four Becoming on Expert on ___ readings and questions
Trade winds / Southern Oscillation / Walker Circulation
El Niño – Warm Phase
La Niña – Cold Phase
Impact of ENSO on Climate Variability
Three sections of ENSO Jigsaw Worksheet
ENSO Jigsaw – Pacific Ocean Aspects
ENSO Jigsaw – U.S. Climate Variability Aspects
ENSO Jigsaw – Worldwide Climate Variability Aspects
ENSO Crossword Puzzle
Other Effects of ENSO
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.
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
Questions Concerning Trade Winds/Southern Oscillation/Walker Circulation
1. The ocean and atmosphere are related. Scientist call this relationship
2. Where are the sea surface temperatures the greatest?
3. What happens to the air when the sea surface temperature heats up?
4. What causes the trade winds?
5. How do the northern and southern trade winds different?
6. How are the trade winds and the ocean coupled?
7. What is the southern oscillation?
8. What is air normally doing where the air pressure is low?
9. What is air normally doing where the air pressure is high?
10. What is the Southern Oscillation a measure of?
11. What is the Walker Circulation?
12. Why is the warm pool so important?
13. How does the thermocline affect the biological make up of the Pacific Ocean?
14. What is upwelling?
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.
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
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.
Questions on El Niño – Warm Phase
1. El Niño phase is also referred to as the __________________ 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?
4. What happens to the southern oscillation pressure difference during an El Niño phase?
5. What happens to the pool of warm water winds during an El Niño phase?
6. What is the definition of an El Niño phase?
7. What happens to the thermocline during an El Niño phase?
8. What happens to the air pressure during an El Niño phase?
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.
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.
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.
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
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.
Questions on La Niña – Cold Phase
1. La Niña phase is also referred to as the __________ ________ 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?
4. What happens to the southern oscillation pressure difference during a La Niña event?
5. What happens to the warm pool of water during a La Niña phase?
6. What is the definition of a La Niña phase?
7. What happens to the thermocline during a La Niña phase?
8. What happens to the air pressure during a La Niña phase?
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.
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.
13. 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.
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.
Questions on ENSO’s Impact on Climate Variability
1. What is a teleconnection?
2. What parts of the world have teleconnections been made between ENSO and climate
conditions?
3. Where are the strongest ENSO impacts found?
4. Two important points are discussed in the information regarding ENSO’s affect on climate
variability. Explain those two points in your own words.
5. Why is a change in the jet stream important in determining climate variability for the U.S.?
6. What happens to the Pacific jet stream during an El Niño phase during January to March?
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?
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.?
9. What happens to the Pacific jet stream during a La Niña phase during January to March?
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?
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?
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.
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
Warm Pool of Water - importance
Thermocline
Trade Winds / Walker Circulation
Jet Stream
Another Phase Name
No Definition
Southern Oscillation
Upwelling - Biological
Anomaly from Normal
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
El Nino – Warm Phase
2. What is a teleconnection?
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?
4. What is the typical anomaly associated with La Niña phase for precipitation and temperature
in Texas?
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.
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.
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?
3. Why do you think much of the research into ENSO has originated in Australia?
Yes
No
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
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?
2. During what El Niño season were forest fires most predominant?
3. What country has suffered the most recently from the effects of forest fires associated with
the El Niño phase?
4. Why do some areas see an increased probability of flooding during an El Niño year?
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?
6. How does an El Niño event affect the number of hurricanes affecting the U.S.? Hint:
consider both Atlantic and Pacific Oceans.
7. How does a La Niña event affect the number of hurricanes affecting the U.S.? Hint: consider
both Atlantic and Pacific Oceans.
8. During an El Niño phase 1.04 hurricanes always hit the U.S. True or false and why?
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?
10. Besides ENSO what other factors are important in determining if a disease outbreak occurs.
11. Countries that normally have high precipitation levels may see an increase in malaria during
ENSO phases that bring decreased precipitation. Why?
12. Countries that normally have low precipitation levels may see an increase in malaria during
ENSO phases that bring increased precipitation. Why?
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