El Niño has passed peak strength but impacts will continue, UN warns

Current climate event is still strong but it is too early to say whether it will be most powerful on record, says World Meteorological Organisation
Adam Vaughan and John Vidal The Guardian 18 Feb 16;

The El Niño that caused record temperatures, drought and floods over the last year has passed its peak strength but will continue to have humanitarian impacts for months to come, the UN has said.

The World Meteorological Organisation (WMO) said the event, which plays havoc with weather systems around the world, was still strong and its impacts on communities in southern Africa, the Horn of Africa and Central America were becoming increasingly apparent.

El Niño is a global climate phenomenon that occurs every few years when a huge warm patch of water forms in the western tropical Pacific Ocean, affecting rainfall from the the western US and South America to Africa, India, Indonesia, and Australia. The UN World Food programme warned earlier this week that 100 million people were facing food and water shortages as a result of the El Niño.

The WMO said that although the current episode was closely comparable in strength with the record event of 1997-98, it was too early to say whether the 2015-16 El Niño was the strongest ever. The agency’s confirmation that the peak has passed follows similar recent announcements by national science agencies.

The WMO’s new secretary general, Petteri Taalas, said: “In meteorological terms, this El Niño is now in decline. But we cannot lower our guard as it is still quite strong and in humanitarian and economic terms, its impacts will continue for many months to come.”

He added: “Parts of South America and east Africa are still recovering from torrential rains and flooding. The economic and human toll from drought - which by its nature is a slowly developing disaster - is becoming increasingly apparent in southern and the Horn of Africa, Central America and a number of other regions.”

In a joint statement, the UN’s World Food programme, the European commission, the US government’s Famine Early Warning System and the UN’s Food and Agriculture Organisation (FAO) warned on Thursday that staple food harvests across much of southern Africa would be badly hit throughout 2016.

“Much of southern Africa has experienced significant delays in planting and very poor conditions for early crop development and pasture regrowth. In many areas, planting has not been possible due to 30 to 50-day delays in the onset of rains and there has been widespread crop failure,” said the agencies.

South Africa, the breadbasket of the region on which many southern African countries depend for food imports in times of drought, this week issued a preliminary forecast of maize production for the coming harvest of 7.4 million tonnes, a drop of 25% from the already poor production levels of last season and 36% below the five-year average.

“Seasonal [weather] forecasts are predicting a continuation of below-average rainfall and above-average temperatures across most of the region for the remainder of the growing season. The combination of a poor 2014-15 season, an extremely dry early season (October to December) and forecasts for continuing hot and drier-than-average conditions through mid-2016, suggest a scenario of extensive, regional-scale crop failure”, said the FAO.

El Niño has played a key part, along with climate change, in driving global temperatures to record levels in 2015 and January 2016. The WMO said the current episode would likely fade away during the second quarter of 2016.

El Niño passes its peak while La Niña is possible this year
Matt McGrath BBC 19 Feb 16;

The El Niño weather phenomenon has reached its peak according to scientists and is set to decline over the next few months.

Researchers say there is a 50:50 chance that it will be replaced by a La Niña event before the end of this summer.

La Niña which involves a cooling of the Pacific Ocean, usually brings wetter conditions to Asia, Africa and Latin America.

These events can typically last twice as long as an El Niño.

Warmest January on record

While the World Meteorological Organisation (WMO) reports that the El Niño event has reached its apex, it is still having a significant influence on the global climate.

In combination with human induced warming, global temperatures in January were the hottest for the month since records began in 1880. The data also showed the biggest divergence yet seen from the long term record.

"In meteorological terms, this El Niño is now in decline. But we cannot lower our guard as it is still quite strong and in humanitarian and economic terms, its impacts will continue for many months to come," said Petteri Taalas from the WMO.

"Parts of South America and East Africa are still recovering from torrential rains and flooding. The economic and human toll from drought - which by its nature is a slowly developing disaster - is becoming increasingly apparent in southern and the Horn of Africa, central America and a number of other regions," he said.

While the El Niño did bring some relief to drought-hit California, there have been concerns that it has tapered off in recent weeks.
But in the wake of El Niño, experts believe there is a good chance that a La Niña will arrive later this year .

"Most models indicate that El Niño will weaken, with a transition to neutral during the late spring or early summer 2016," according to the US Climate Prediction Centre.

"Thereafter, the chance of La Niña conditions increases into the autumn," they concluded.

According to the US National Oceanic and Atmospheric Administration (NOAA), there is a 50% chance of a La Niña this summer. They say that there is an 80% chance of it happening by the end of this year.

Not every weather centre is on the same page when it comes to predicting the appearance of the event that's also termed El Viejo (the old one) or the Anti-El Niño .

Australia's Bureau of Meteorology says that based on 26 El Niño events since 1900, around half have been followed by a neutral year while 40% have been followed by La Niña. They argue that international climate models right now suggest that there won't be a follow-on La Niña this year.

If forecaster are a little uncertain of the arrive of a La Niña, they are all remaining tight-lipped on the more important question of how powerful it is likely to be.

La Niña often improves fishing conditions in the Pacific Ocean off South America, thanks to the upwelling of cold, nutrient-rich waters.
It is also associated with heavier monsoons in South-East Asia, but it has also caused significant flooding in Australia in the recent past.

Another outstanding question is the impact of climate change on La Niña. A study last year suggested that extreme events were much more likely in a warming world.