(3) References for el nino cause and effects essayBelow are 3 fu.docxkatherncarlyle
(3) References for el nino cause and effects essay
Below are 3 full text sources from Proquest data base to be used for this essay. Please use in text citations in the body of the essay and create a works cited section at the end of the essay. I have already cited each source for you at the beginning of each source above the title (see below).
Perera, J. (1997, Dec 26). EL NINO - THE GLOBAL WEATHER PHENOMENON. Inter Press Service Retrieved from http://search.proquest.com/docview/446072605?accountid=8289
EL NINO - THE GLOBAL WEATHER PHENOMENON
LONDON, Dec. 26 (IPS) -- In March 1997, sea-surface temperatures in the Pacific Ocean began increasing -- the beginning of the "El Nino" weather system that, linked with the so-called "Southern Oscillation," has become notorious its global effects.
The El Nino of 1982-83 caused severe flooding and weather damage in Latin America as well as drought in parts of Asia. The last event, in 1991-92 brought severe drought to Southern Africa.
This year's El Nino is regarded by various experts as one of the most severe this century with record Pacific surface temperatures.
It is expected to continue well into 1998.
El Nino was the name given by the fishermen of northern Peru during the 19th century to describe the flow ofwarm equatorial waters southward around Christmas time. Normally the waters were cold and flowed from south to north.
But periodically the waters would reverse their flow and become warm. This caused the fish food chain to collapse as the warm current blocked the nutrient-rich cold water that rises from the bottom of the ocean. The fish died or moved away and catches would fall. This usually reached its peak around Christmas holiday, and the sailors named it "El Nino" (the Christ Child).
However, Peruvian scientists later linked more intense changes that took place every few years with catastrophic seasonal flooding along the normally arid coast.
At the beginning of the 20th century, British climatologist Gilbert Walker, head of the Indian Meteorological Service, began to investigate connections between the Asian monsoon and other climatic changes. He had been asked in 1904 to find a way to predict the pattern of India's monsoons after an 1899 famine caused by monsoon failure.
Unaware of El Nino, he discovered a periodic fluctuation of atmospheric pressure over the tropical Indo-Pacific region, which he called the Southern Oscillation (SO). When rainfall was sparse over northern Australia and Indonesia, pressure in that region was unusually high and wind patterns were changed.
At the same time, pressures were unusually low in the eastern South Pacific. Walker devised a "Southern Oscillation Index" (SOI), based on pressure differences between the two regions (east minus west) and in papers published during the 1920s and 1930s, he presented evidence for worldwide climatic changes associated with the SOI pressure "seesaw."
In the 1950s, the low-phase years of the SOI were found to corresponded ...
*You may also download this ppt for better viewing experience :)
This ppt contains a summary of El Niño and La Niña.
It also includes the following:
> ENSO
> Southern Oscillation
> Southern Oscillation Index (SOI)
> Effects of El Niño
> Response to El Niño
> Effects of La Niña
> Response to La Niña
El Niño is a naturally occurring event in the equatorial region which causes temporary changes in the world climate.
Originally, El Niño was the name used for warmer than normal sea surface temperatures in the Pacific Ocean off the coast of South America.
Now, El Niño has come to refer to a whole complex of Pacific Ocean sea-surface temperature changes and global weather events.
The ocean warming off South America is just one of these events.
A guide to prepare for unit 2.6: The Oceans - Environmental Management syllabus 5014. The pictorial content will help understand the Ocean floor topography, Ocean Currents, and El-Nino phenomenon
Increased co2 effect on crop production tam 2013-25
El nino & la nina tam 2013-22
1. EL NINO & LA NINA
R. THANUSHA
TAM/13-22
Dept GPBR
2. Peak El Niño occurs about
Christmas season ...
• “Christ Child”
• “The Boy”
• “The Little One”
• Cf: La Niña
• “The Girl”
3. State Agricultural Response Team 9
• El Niño Phase – Warmer than normal sea surface
temperature in the Pacific Ocean near the equator
Example: Strong El Niño phases in 1982-83 and 1997-
98 caused excessive rainfall on the West Coast and
the Gulf coast
• La Niña Phase – Cooler than normal sea surface
temperature in the Pacific Ocean near the equator
Example: 1998-99 and 1999-2000 La Niña phases
caused drier and warmer winters in Florida. Result:
increase forest fires; drier and warmer than usual
temperatures in other parts of the U.S.
El Niño and La Niña Phases
4. El Niño and La Niña: What are they?
State Agricultural Response Team 8
• Caused by changes in sea surface temperature
(SST) in the equatorial Pacific Ocean
• Strongly influence climate around the world
• Return every 2 to 7 years but do not always
follow each other
• Affect production of winter vegetables and
other crops in the southeast U.S.
11. Neutral Years
State Agricultural Response Team 11
• Neither El Niño nor La Niña phases exist
• Surface water temperatures (SSTs) normal or
near normal; SSTs are different at different
times of the year but are usually from 75˚F to
80˚F in December through February
• Neutral phases are twice as likely to happen
as either El Niño and La Niña
12. State Agricultural Response Team 12
El Niño and La Niña – Impact on
Rain
Temperature
Hurricanes
Wild fires
Crop
production
13. State Agricultural Response Team 16
El Niño and La Niña and Temperature
• El Niño Phase – Temperature 2˚F to 3˚F
below normal in Florida and Gulf Coast
during the winter
• La Niña Phase – Temperatures 2˚F to 4˚F
above normal December through April and
increase farther north in Florida
― La Niña phase average daily minimum
temperatures June through August
likely to be lower than normal in south
Florida
14. El Niño and La Niña and Hurricanes
21
• El Niño Phase – Fewer hurricanes
because upper level winds over
Atlantic Ocean are not suitable;
chance of a hurricane striking the
U.S. is less likely
• La Niña Phase – Helps hurricanes
develop in the Atlantic Ocean;
greater chance that a hurricane
may hit the U.S.
Chance of 2 hurricanes hitting the U.S.:
•28% in El Niño
•48% in Neutral
•66% in La Niña
15. La Niña and Wild Fires
State Agricultural Response Team 23
In La Niña Phase –
• Below normal rain
from fall into April,
one of driest
months of the year
• Soil and forests
extremely dry;
Increased risk of
fires in spring and
summer, especially
in South Florida
16. State Agricultural Response Team 24
Wild Fires
• In El Niño Phase -- Wet
winters seem to lower the
risk of wild fires
• Wild fires usually not a
problem in western
Panhandle -- this area gets
more rain than rest of state
17. 1983 El Niño caused
severe drought, heat waves and
Bushfires in Australia.
Flames devour farmland in Victoria,
Australia.
El Niño triggered prolonged drought
of 1983 made fire a constant hazard.
In 1983, winds whipped fires from
Adelaide to Melbourne, destroying
seven towns and several thousand
homes.
18. • Weakens Indian Monsoon.
• Causes drought in central North America.
El Niño plays with world weather
Fires in the Amazon Worsening drought in Sahel
20. Major theories
• Recharge oscillator: Several mechanisms have been proposed where
warmth builds up in the equatorial area, then is dispersed to higher
latitudes by an El Niño event. The cooler area then has to "recharge"
warmth for several years before another event can take place.
• Western Pacific oscillator: In the western Pacific, several weather
conditions can cause westerly wind anomalies. For example, cyclones
north and south of the equator force west-to-east winds between. Such
wind may counteract the typical easterly flows across the Pacific and
create a tendency toward continuing the eastward motion. A weakening
in the westward currents at such a time may be the final trigger needed
to shift into an El Nino.
• Equatorial Pacific Ocean may tend to be near El Niño conditions, with
several random variations affecting behavior. Weather patterns from
outside the area or volcanic events may be some such factors.
• Global warming
21. Forecasts are presented in terms of possible
conditions for South America:
1) near normal conditions,
2) a weak El Niño with a slightly wetter than normal
growing season,
3) a full blown El Niño with flooding,
4) cooler than normal waters offshore, with higher
than normal chance of drought in South America.
Once the forecast is issued, management of
agriculture, water supplies, fisheries, and other
resources can be modified.
22. Weather Forecasts…
25
Help you decide when to
• Plant
• Spray
• Fertilize
• Irrigate
Climate Forecasts…
Help you decide about
• Crop varieties
• Acreage allocation
• Crop insurance
• Marketing strategy
23. State Agricultural Response Team 27
Using Climate Forecasts
EXAMPLE:
During La Niña, central Florida
strawberry growers plant varieties
suitable for increased solar
radiation
EXAMPLE:
During El Niño, potato growers crown
fields and maintain drainage
24. State Agricultural Response Team 29
Climate Forecasts
EXAMPLES:
• Citrus growers irrigate
to maintain soil
moisture during La Niña
winters
• Farmers decide on crop
insurance and how
much coverage to buy
28. TEMPERATURE
Blue circles are colder during El Niño and/or
warmer during La Niña. The size of the circles
is a measure of the strength of the
relationship.
Red circles denote locations that on average
are warmer during El Niño and cooler during
La Niña.
EFFECTS
29.
30.
31.
32.
33. IMPACT
In Australia, the impact event of El Niño has not been as strong
as anticipated.
In Indonesia, late-arriving rains delayed the normal
October/November rice planting and caused a reduction in rice
production potential.
In Malaysia, rainfall has been below normal but adequate for
rice production.
In Thailand, below normal rainfall has lowered water reserves
for the second rice crop.
In the Philippines, localized dryness has reduced corn and rice
yields.
34. IMPACT
In the Republic of South Africa, November/December corn
planting was delayed due to insufficient rainfall.
In Zimbabwe, there is a hot dry December
In Tanzania and Kenya, drought earlier in the crop year
In India past El Niño brought dry weather across
northwest India
In the Central America the major El Niño impact is nearly
over as their rainy season has ended.
35. Detection and Prediction
There are several means used for El Niño detection;
satellites, moored ATLA and PROTEUS buoys, drifting buoys,
sea level analysis, and XBT's. Since El Niño influences global
weather patterns and affects human lives and ecosystems,
prediction of an El Niño event is becoming increasingly
important. For short term prediction (up to 1 year) of climate
variations, current observation in the Tropical Pacific are vital.
Numerical models are used in many places for El Niño
prediction and research. Here are some of the latest El Niño
forecasts.
36. MITIGATION
Recent technological advances have made it possible to
monitor, diagnose, and predict El Niño and La Niña events in
near-real time. Some of the major technologies used are:
Satellite Ocean buoysRadiosondes
Super computers
39. Given that numerical models predicting El Niño
must do so months in advance,
they are not as reliable as those used in predicting the
weather, which forecast only days in advance. They have,
however, progressed to the point where they can
reproduce the characteristics of a typical El Niño event
and some industries use these forecasts as an indicator of
the coming fish harvest.
40. Why is predicting El Niño and La Nina so important?
Better predictions of the potential for extreme climate episodes
like floods and droughts could save the United States billions
of dollars in damage costs.
Predicting the life cycle and strength of a Pacific warm or cold
episode is critical in helping water, energy and transportation
managers, and farmers plan for, avoid or mitigate potential
losses.
Advances in improved climate predictions will also result in
significantly enhanced economic opportunities, particularly for
the national agriculture, fishing, forestry and energy sectors, as
well as social benefits.
