What is El Niño?

What is El Niño and how often does it occur?

El Niño is a term for the warming phase of the El Niño Southern Oscillation (ENSO). It is a warming of the central to eastern tropical Pacific that occurs, on average, every three to seven years. During an El Niño event, sea surface temperatures across the Pacific can warm by 1–3°F or more for anything between a few months to two years. El Niño impacts weather systems around the globe so that some places receive more rain while others receive none at all, often in a reversal of their usual weather pattern. 

Why is everyone so concerned this year?

There were super El Niño events in 1972-73, 1982-83 and in 1997-98, the latter bringing record global temperatures alongside droughts, floods and forest fires. The current El Niño has already affected millions of people and comes on top of already volatile and erratic weather patterns linked to climate change. 2014 and 2015 were the hottest years on record, with the Pacific Ocean already warming up to an unprecedented degree.

Is this the strongest El Niño on record?

The World Meteorological Organization’s (WMO) position is that the current El Niño event is one of the three strongest since 1950. As El Niño events are measured in multiple ways, this event is the strongest according to some metrics, but not others. Further, the effects of El Niño varies across regions, and an El Niño event can still be devastating without being the ‘strongest’.

Is El Niño caused by climate change?

No. El Niño events are not caused by climate change – they are a natural reoccurring phenomenon every several years – but scientists believe they may be becoming more intense as a result of climate change. Exactly how El Niño interacts with climate change is not 100 percent clear. Nonetheless, many of the countries now experiencing El Niño are also those that face the gravest threat from climate change.

What is La Niña and what do we expect from it?

La Niña is the cooling phase of the ENSO. It is characterised by a cooling of equatorial waters in the Pacific and tends to have global climate impacts opposite to those of El Niño. Historical patterns show that a La Niña sometimes follows an El Niño and that it can have an even greater overall humanitarian impact on average as coping capacities are eroded. If a La Niña event develops, it will more likely be in late 2016 or early 2017. Ocean temperatures around March will be key to judge the risk of a strong La Niña. National Meteorological and Hydrological Services, WMO Regional Climate Centres, and other agencies will continue to monitor the conditions over the tropical Pacific for further El Niña evolution..

El Niño has peaked. Does that mean that the danger has passed?

No. While El Niño has peaked, the impact of drought or excessive rainfall on food production and health can last for many months beyond the peak of the weather event. Similarly, it can take months to overcome the impact of damage to infrastructure and the depletion of assets such as livestock. In some agricultural areas, one or more successful cropping seasons will be necessary to fill the hunger gap. Even as El Niño weakens, it is important to continue to support those affected and to make early, ‘no regrets’ investments to mitigate the impact of a possible La Niña episode to follow.

What is the humanitarian impact of El Niño?

Over 60 Million people will be impacted by El Niño this year though an exact number is hard to pinpoint. Climate forecasters predict East Africa, Southern Africa, the Pacific Islands, South East Asia and Central America are most at risk of extreme weather, including below-normal rains and flooding. The humanitarian fallout in certain areas will include increased food insecurity due to low crop yields and rising prices; higher malnutrition rates; devastated livelihoods; and forced displacement. Excessive rainfall could also trigger and exacerbate outbreaks of waterborne diseases such as cholera and typhoid as well as vector-borne diseases such as malaria, which will affect millions of people. [See: El Niño: Overview of Impact, Projected Humanitarian Needs and Response - as of 29 Jan 2016]. 

What will be the impact on food prices?

Globally, cereal production in 2015 is not much lower than 2014’s record levels according to the World Food Programme (WFP) as production shortfalls are balanced by increased production elsewhere. However, some countries and regions are experiencing localised problems where drought is impacting production. AS an example prices of yellow and white maize in South Africa reached new record highs. South Africa will need to import 5 to 6 million tons of maize to and at least 2 million tons of wheat, as well as soya beans. The food security effects will be worse for regions like the Horn of Africa, which are already suffering cumulative effects of past poor growing seasons. In highly import-dependent regions such as West Africa, consumers will face food insecurity due to increased prices of staples such as rice. 

What’s being done about El Niño? 

National governments, the UN and NGOs are monitoring conditions on the ground and raising the alarm in countries at risk. OCHA has produced analyses on the current and projected humanitarian impact of El Niño in Asia, the Pacific, Southern Africa, Latin America and Eastern Africa. Humanitarian Country Teams are working closely with governments and developing preparedness and response plans in countries at risk or affected already, with a focus on responding early to the humanitarian needs that are emerging. The Central Emergency Response Fund (CERF) has allocated more than $63 million to aid agencies to respond to drought, drought-like situations and floods linked to El Niño.

Many response plans face severe funding gaps and more robust support to these efforts is urgently needed to mitigate the effects of El Niño. Early action is critical to help reduce vulnerability and the need for humanitarian assistance. El Niño will continue over the coming months and the investments made now will have an enormous return, both in terms of alleviating suffering and avoiding soaring costs. NGO Oxfam strikes a cautionary note, pointing to the impact of the slow international response to early warning of looming famine in the Horn of Africa in 2011, when millions of people suffered and 260,000 died. “We need to act now … the same must not happen in 2016.”
Sources: UNOCHA, World Food Programme, Oxfam, CARE International and US National Ocean Service



The El Niño of 2015-2016 (WMO)