An international team of scientists forecast an 80% chance next year of an El Niño, which occurs when sea-surface temperatures rise substantially above normal in the east-central Equatorial Pacific.
The complex El Niño weather pattern that can bring disastrous heavy rainfall and long droughts to countries around the Pacific — from Peru to Indonesia and Australia — will probably emerge again in 2020, researchers have predicted.
They said their model — which uses an algorithm that draws on analysis of links between changing air temperatures at a network of grid points across the Pacific region — could predict an El Niño at least a year ahead.
“Conventional methods are unable to make a reliable ‘El Niño’ forecast more than six months in advance. With our method, we have roughly doubled the previous warning time,” said co-developer Armin Bunde, a physicist at Germany’s Justus Liebig University Giessen.
The term El Niño, meaning “boy child” in Spanish, was first used in the 19th century by fishermen in Peru and Ecuador to refer to the unusually warm waters that reduced their catch just before Christmas, according to the World Meteorological Organization (WMO).
The phenomenon occurs every two to seven years and typically lasts for 9-12 months, often beginning mid-year and peaking between November and January.
Hans Joachim Schellnhuber, director emeritus of the Potsdam Institute for Climate Impact Research (PIK), said insights from the new method — which has been tested over the past few years — would be made available to people affected by El Niño.
PIK researcher Josef Ludescher said he would soon discuss the findings with the weather service in Peru.
El Niño often brings torrential rains in the north of the mountainous Latin American nation, with a high risk of mudslides, he said.
El Niño also can cause extended droughts in other parts of South America, Indonesia, Australia and Africa, PIK said. In the Indian subcontinent, it may change monsoon patterns, while California can experience more precipitation.
The new prediction method could give more time for authorities to prepare for such impacts, Mr. Ludescher added.
The team is now adapting the algorithm to be able to predict the timing and strength of El Niño.
In the future, a similar method could be used to improve forecasts of Asia’s monsoon, he told the Thomson Reuters Foundation.
The discovery of the new method was first published in 2013 in the Proceedings of the National Academy of Sciences journal — and the scientists have since been checking its accuracy.
They said this week it correctly predicted the onset of the large El Niño that started in 2014 and ended in 2016 and the most recent event in 2018, as well as absences in other years.
The next expected El Niño, due to peak in late 2020, could push global average annual temperature rise to a new record in 2021, the researchers said.
Air temperature rise lags Pacific warming by about three months, they noted.
According to the WMO, 2016 became the warmest year on record because of the powerful El Niño in 2015-2016, combined with long-term climate change.
Last year, WMO predicted the 75-80 percent chance of a full-fledged El Nino from January to March of 2019.
It added such a phenomenon increased in intensity and frequency as the planet warms, worsening their related extreme weather impacts.
The changes drive weather patterns that have global consequences like below-average temperatures and more rain for the southern U.S., but hot dry conditions for Australia, Philippines, Indonesia, southeastern Africa and northern Brazil.
Typically, El Niño years occur after every seven to ten years, affecting more than 60 million people, causing droughts, wildfires and causing devastating coral bleaching.
Impact on Food Production
Farming is one of the main sectors of the economy that could be severely affected by the El Niño phenomenon. While drought is the main threat to food production, El Niño can also cause heavy rains, flooding or extremely hot or cold weather.
According to the UN Food and Agricultural Organization (FAO), this can lead to pest and disease outbreaks and animal diseases like zoonosis and food-borne infectious ailments.
It also causes widespread forest fires.
In previous El Niño events, people whose livelihoods depend on fisheries have been heavily affected in certain areas.
This year’s El Nino is going to affect fourteen countries in Africa, the South Pacific, Asia and Central America due to their increased risk to extreme weather while another 19 countries are classed as facing moderate risk.
The above-average ocean temperatures mean that fish migrate further north in search of cooler waters, and their predators follow suit. These migrations affect not only the marine food chain, but also humans that depend on those fish populations for nutrition and income.
El Niño also causes a shift in precipitation, which means some areas may get more rain than usual while others get less, which affects agriculture.
UNFAO said it is observing the current El Nino event and designing and implementing early actions to reduce the effects on vulnerable populations in all high-risk countries and in some of the countries at moderate risk.
In Somalia, riverbanks are being reinforced and sandbagged and plastic is being distributed to protect seed stocks.
FAO is expanding operations in response to growing food insecurity as a result of poor harvests across much of southern Africa. In Malawi, the Organization is assisting governments in the preparation of food insecurity response plan.
In Zimbabwe, FAO is providing support to 40 000 smallholder households to engage in commercial livestock production, and responding to the foot and mouth disease outbreak where 5.4 million doses of vaccines are still required. FAO has also prepared a drought mitigation programme.
FAO is supporting the countries of the dry corridor in Central America to increase the resilience of households, communities and institutions to prevent and address disaster risks that affect agriculture and food and nutrition security in a timely and efficient manner.
El Nino can have profound effects on human societies and ecosystem. It influences extreme events such as drought, floods, and tropical cyclones in many regions of the world, and these conditions can impact agriculture and food security, water resources and health.
Nearly three decades ago, the development of forecasts of El Niño events captured the attention of natural and social scientists, policy makers and resource managers who were eager to see these predictions put to use.
The forecasts on El Niño in most of the tropics and much of the sub-tropics where the phenomenon is most felt benefitted the agricultural sector especially water resources management. It helped farmers about the precise amount of rain in one specific farm, and about the timing of rainfall during the rainy season, while water managers made use of forecasts to plan water conservation.
Impact on Ecosystems
El Nino can have devastating impact on everything from weather systems to ecosystems around the world.
But since El Nino isn’t always predictable, so are its effects. In some parts of world crops may fail due to drought or floods. California may have a drought, and Manila may be flooded.
In the past, Bolivia, Colombia, Ecuador, Peru and Venezuela have already seen bridges, homes and hospitals destroyed by flooding. Crops have been ruined, and the mining industry has cut exports. All this is destabilizing emerging economies.
The situation maybe equally drastic in Indonesia where droughts have hit the country particularly hard, affecting industries like mining, power, cocoa, and coffee.
But biodiversity also pays a price. El Nino can impact the natural world. Much of Australia’s wildlife is adapting to the variable weather caused by El Nino – which appears to trigger green turtle breeding and changes in duck populations.
Also, underwater ecoystems supported by coral reefs are among El Nino’s casualities Native species not only have to cope with the changing weather, but also out-compete with generalist invaders.
The islands’ marine birds – like the blue-footed booby, brown pelican and frigate bird – are struggling to feed their offspring, and are laying fewer eggs. Galapagos penguins and flightless cormorants are also heavily affected by the lack of food.
In marine ecosystems, El Nino is causing sea temperatures in the Pacific Ocean to rise, contributing to corals bleaching. Increasingly strong waves relating to El Nino, along with exploding populations of sea urchins, are also having a devastating impact on the complex coral habitats that sustain a multitude of species.
Meanwhile, the production of phytoplankton is decreasing, causing repercussions through the food chain so that even top predators like sea lions are going hungry due to sea temperature rise.
Algal beds suffer too, affecting the animals that feed on them, including marine iguanas, turtles and many species of fish. Migratory species like sharks are being forced to move further offshore and forage in deeper waters.