The global El Niño weather phenomenon,
whose impacts cause global famines, floods – and even wars – now has a
90% chance of striking this year, according to the latest forecast
released to the Guardian.
El Niño begins as a giant pool of warm water swelling in the eastern
tropical Pacific Ocean, that sets off a chain reaction of weather events
around the world – some devastating and some beneficial.
India is expected to be the first to suffer, with weaker monsoon
rains undermining the nation’s fragile food supply, followed by further
scorching droughts in Australia
and collapsing fisheries off South America. But some regions could
benefit, in particular the US, where El Niño is seen as the “great wet
hope” whose rains could break the searing drought in the west.
What is El Niño
The knock-on effects can have impacts even more widely, from cutting global gold prices to making England’s World Cup footballers sweat a little more.
The latest El Niño prediction comes from the European Centre for Medium-range Weather Forecasts
(ECMWF), which is considered one the most reliable of the 15 or so
prediction centres around the world. “It is very much odds-on for an
event,” said Tim Stockdale, principal scientist at ECMWF, who said 90%
of their scenarios now deliver an El Niño. "The amount of warm water in
the Pacific is now significant, perhaps the biggest since the 1997-98
event.” That El Niño was the biggest in a century, producing the hottest
year on record at the time and major global impacts, including a mass die-off of corals.
“But what is very much unknowable at this stage is whether this
year’s El Niño will be a small event, a moderate event – that’s most
likely – or a really major event,” said Stockdale, adding the picture
will become clearer in the next month or two. “It is which way the winds
blow that determines what happens next and there is always a random
element to the winds.”
The movement of hot, rain-bringing water to the eastern Pacific ramps
up the risk of downpours in the nations flanking that side of the great
ocean, while the normally damp western flank dries out. Governments, commodity traders, insurers and aid groups like the Red Cross and World Food Programme all monitor developments closely and water conservation and food stockpiling is already underway in some countries.
Professor Axel Timmermann, an oceanographer at the University of Hawaii,
argues that a major El Niño is more likely than not, because of the
specific pattern of winds and warm water being seen in the Pacific. “In
the past, such alignments have always triggered strong El Niño events,”
he said.
El Niño events occur every five years or so and peak in December, but
the first, and potentially greatest, human impacts are felt in India.
The reliance of its 1 billion-strong population on the monsoon, which
usually sweeps up over the southern tip of the sub-continent around 1
June, has led its monitoring to be dubbed “the most important weather
forecast in the world”. This year, it is has already got off to a delayed start, with the first week’s rains 40% below average.
A farmer awaits rain on his drought-hit paddy field in Morigoan, Assam, India. Photograph: Manoj Deka/Corbis
“El Niño could be quite devastating for agriculture and the water
supply in India,” said Dr Nick Klingaman, an El Niño expert at the
University of Reading in the UK. Two-thirds of Indian farmland lacks
irrigation and is reliant solely on rainfall, meaning even current
official prediction of a 5% reduction in monsoon rains would have a
major impact: a 10% fall is an official drought. Krishna Kumar, an
Indian meteorologist and El Niño expert, said that even if the 2014 El
Niño turns out not to be a very hot one, it can still have a major
effect on the monsoon because it is the specific location of the warm Pacific water which is the critical factor.
“The moderate El Niños of 2002 and 2009 impacted the monsoon in India
much more greatly then the major 1997 event,” he said, adding that the
biggest cut in rainfall is not usually felt until September.
Share your stories How has El Niño weather phenomenon affected you?
El Niño, in 1997-98, resulted in the hottest
year on record, and the accompanying floods, cyclones, droughts and
wildfires killed an estimated 23,000 people and caused £21bn-£28bn in
damage, particularly to food production. How were you affected by it,
and how are you preparing this year?
Rana Kapoor, president of the Associated Chambers of Commerce of India,
warned: “We recommend the government to immediately announce steps to
control food inflation in view of the impending El Niño and the
cascading negative affect it will have on crop production.” The impact
on farmers means past monsoon failures have cost the nation $20bn
(£12bn) in lost output and, because the Indian market dominates global
gold prices, the cost of the precious metal has already fallen.
Global sea surface temperature in May 2013 and May 2014. Photograph: NASA
New research in May showed the global impact of El Niño events on food supplies,
with corn, rice and wheat yield much lower than normal, although
soybean harvests tend to rise. While food production has improved in the
last year, El Niño is set to reverse that trend, according to Leo
Abruzzese, global forecasting director for the Economist Intelligence
Unit. “It may reduce agricultural output over the next few years, which
could weigh on global food security”. Drought linked to the 2007 El Niño led to a surge in food prices in 2008 that sparked riots in countries as far afield as Egypt, Cameroon and Haiti.
After India, El Niño’s impacts roll eastwards and officials in Cebu, the Philippines’ second city, have already urged all households to save water to reduce the impact of the drier weather due to hit by the end June. In Malaysia, the national water authority is preparing for a dry spell of up to 18 months and calling for water rationing, while meteorologists have warned of forest fires.
The hot, dry skies will then track to heat-wracked Australia, where
2013 was already its hottest year on record and El Niño is threatening
to turn the temperature up even further. Andrew Watkins, manager of
climate prediction services at the Australian Bureau of Meteorology,
said: “El Niño is one of the largest influences on Australia’s climate.
It’s why historically Australia has had one of the most variable
climates on the planet.” Watkins said El Niño increases the chances of
low rainfall in the country’s southern and most populous half and tends
to deliver hotter years and higher extreme temperatures.
Low water levels at Lake Hume, on the Victoria-NSW border, Australia,
during the dry summer of 2007, when the last El Niño occurred.
Photograph: Ashley Whitworth/Alamy
Brent Finlay, president of Australia’s National Farmers’ Federation,
said he was hoping El Niño just does not happen. “We have farmers and
graziers in New South Wales and Queensland who are in drought now, and
so to have this prediction of a possible El Niño will be of grave
concern.” Severe drought at any time could have “tragic” consequences on
rural communities where he said some farmers had even taken their own
lives, he said: “That is what drought does.”
However, on the opposite side of the Pacific, in the US, El Niño
holds out the prospect of relief for the parched western states and
nowhere is more desperate for rain than California. The entire state is in severe or extreme drought,
after receiving barely a quarter of its annual rainfall, and
communities have been under water rations since March, which ordinarily
would still be the rainy season. The result is a tinder box, with
governor Jerry Brown warning the state faces the worst wildfire season
on record.
A strong El Niño would bring rain, typically double the annual
average in southern California. “I commonly refer to El Niño as the
great wet hope,” said Bill Patzert, a climate scientist at Nasa’s Jet
Propulsion Laboratory in California. “Everyone in the west has their
fingers crossed because we are bone dry. We have had three of the four
driest years in the west in recorded history. Dry land farmers and
ranchers are definitely on their knees right now. We are running on
reserves, we are pumping aquifers, and our reservoirs are at record
lows.” El Niños also typically lead to wetter winters in Texas, and
other parts of the south-west, which also depend on getting most of
their rain in the winter months.
Griffith Observatory stands as clouds gather above the skyline of
downtown Los Angeles, California. Photograph: Patrick T. Fallon/Getty
Images
However, big El Niños like the 1997-98 event – what Patzert calls “godzillas” – are rare and forecasters at the US government’s climate prediction centre said on 5 June
that time was running out for a significant El Niño to be set in train.
A modest or small El Niño would have little impact on the drought, said
Patzert, noting that the 2006-07 drought – the worst on record at the
time – occurred during a weak El Niño year. Even a “godzilla” would not
be enough on its own to bail California out, he said: “But it would be a
fantastic down payment on drought relief.”
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El Niños also typically bring warmer winters to the northern US states,
which would be a relief after last winter’s Arctic conditions.
El Niños also typically damp down hurricane activity. But Prof Kerry
Emanuel, an atmospheric scientist at MIT, said even in an El Niño year a
hurricane, given the right conditions, could still cause tremendous
destruction. Hurricane Andrew, one of the deadliest and costliest in
recent history, roared through Florida in 1992, which was an El Niño
year. “It would be tragic if everyone let their guard down,” Emanuel
said.
Elsewhere in the Americas,
a careful watch is being kept in Peru, where the huge anchovy fishery
has been wiped out by previous El Niños – it was Peruvian sailors who
first named the phenomenon “the Christ child” because its peak occurs at
Christmas. The 1997-98 El Niño slashed the catch by 80%, as the fish
migrated away from the abnormally warm waters. Luis Icochea, a fisheries
expert at the National Agrarian University in Lima, warned that the
event this year is developing in a similar way.
Rodney Martínez, at Ecuador’s International El Niño Centre, said El
Niño would affect the whole of south America, meaning heavy rainfall and
floods in Ecuador, Peru, Chile and northern Argentina but potential
drought relief in Chile and Bolivia. The early effects of El Niño in
Brazil are expected to raise temperatures during the football World Cup.
Flooded streets in the town of Tuman, Peru. Photograph: Jaime Razuri/AFP/Getty Images
But, despite better El Niño warnings nowadays, Martinez said many
nations were worse prepared than in 1997: “In many cases the
vulnerability has increased: more exposed population, more land
degradation, river sedimentation, collapse of underground water sources,
degradation of natural protection in riversides, badly designed
infrastructure and lack of coordination and planning to cope with El
Niño.”
Stockdale said other global impacts could be droughts in the
Caribbean and southern Africa at the end of the year, and also in
central Asia, although the precise impacts of each El Niño vary due to
local climatic variations. Europe is the continent least affected by El
Niño by virtue of being on the opposite side of the world.
However, in the tropics and sub-tropics, another deadly impact of El
Niño is becoming better understood: its ability to spark civil wars.
Solomon Hsiang, at Columbia University, New York, showed in 2011 that 50 of the 250 conflicts between 1950 and 2004 were triggered by the El Niño cycle, probably due to the loss of crops, jobs and the psychological effects of hotter weather.
Predicting El Niño blindfolded?
Hsiang told the Guardian that, based on historical data, a Pacific
warming of 0.8C is associated with a rise in the annual risk of conflict
of 15%. The current forecasts indicate that this year’s warming will
most probably lie between 0.5C and 1.5C. “Of course, conflicts may not
occur just because the risk of conflict is higher, in the same way car
accidents don’t always occur on rainy days when the risk of accident is
higher,” Hsiang said. “But it is certainly a developing situation that
we should keep track of and it would be excellent to have policy-makers
and the public aware of the potential risk.”
Policymakers are likely also to feel the heat of El Niño in the
negotiations towards a global deal to cut carbon emissions and tackle
global warming, which must culminate in Paris in December 2015. Since
the scorching year of 1998, the rate of global warming has slowed, with over 90% of the heat trapped by CO2 going into the oceans.
“A lot of energy that should have been in the atmosphere has gone
into the Pacific,” said Kumar. “If El Niño does set in that could
trigger the release of that heat and faster warming: that has been a
major concern.” An El-Niño-boosted 2015 could well be the hottest year
on record, according to Klingaman, just as nations have to agree a
climate change deal.
“If 2014 turns out to be an El Niño year as currently forecast,
increased public awareness of the dangers of human-induced climate
change is likely to follow,” said Prof Michael Raupach, director of the
Climate Change Institute at the Australian National University.
“However, it is very important that our policy responses do not wax and
wane with El Niño.”
The link between global warming and El Niño, a natural climate
phenomenon, is not yet well understood by scientists. But a study
published in January predicted a doubling of extreme El Niño events, as climate change ramps up.
Either way, adding the impacts of El Niño to the extreme weather already being driven by climate change
increases the damage caused, said Stockdale: “El Niño can be the thing
that pushes you over the edge. It will be in the years when you get a
big El Niño when you feel the impact of climate change the most.”
El Niño is a climate phenomenon
that occurs when a vast pool of water in the western tropical Pacific
Ocean becomes abnormally warm. Under normal conditions, the warm water
and the rains it drives are in the eastern Pacific.
El Niño occurs every few years. Its most direct impacts are
droughts in normally damp places in the western Pacific, such as parts
of Indonesia and Australia, while normally drier places like the west
coast of South America suffer floods. But the changes affect the global
atmospheric circulation and can weaken the Indian monsoon and bring
rains to the western US.
It is not certain what tips the unstable Pacific Ocean-atmosphere
system into El Niño, but a weakening of the normal trade winds that blow
westwards is a key symptom. In 2014, the trigger may have been a big
cluster of very strong thunderstorms over Indonesia in the early part of
the year, according to Dr Nick Klingaman from the University of Reading
in the UK.
An
El Niño is officially declared if the temperature of the western
tropical Pacific rises 0.5C above the long-term average. The extreme El
Niño year of 1997-98 saw a rise of more than 3C.
El Niño is one extreme in a natural cycle, with the opposite
extreme called La Niña. The effect of climate change on the cycle is not
yet understood, though some scientists think El Niño will become more
common.
El Niño is a climate phenomenon that occurs when a vast pool of water in the western tropical Pacific Ocean becomes abnormally warm. Under normal conditions, the warm water and the rains it drives are in the eastern Pacific.
El Niño occurs every few years. Its most direct impacts are droughts in normally damp places in the western Pacific, such as parts of Indonesia and Australia, while normally drier places like the west coast of South America suffer floods. But the changes affect the global atmospheric circulation and can weaken the Indian monsoon and bring rains to the western US.An El Niño is officially declared if the temperature of the western tropical Pacific rises 0.5C above the long-term average. The extreme El Niño year of 1997-98 saw a rise of more than 3C.
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