El Nio expected to strengthen further by year-end, UN agency says

A “mature and strong” El Niño event, which is contributing to extreme weather patterns, is expected to strengthen further by the end of the year, according to the latest update from the World Meteorological Organization (WMO), a specialized agency of the United Nations.

The WMO said in a statement on Monday that peak three-month average surface water temperatures in the east-central tropical Pacific Ocean will exceed 2 degrees Celsius above normal, placing this El Niño event among the three strongest since 1950. Strong previous El Niños were in 1972-73, 1982-83 and 1997-98.

The El Niño-Southern Oscillation is a naturally occurring phenomenon which is the result of the interaction between the ocean and atmosphere in the east-central Equatorial Pacific, WMO explained in the statement. Typically, El Niño events peak late in the calendar year, with maximum strength between October and January of the following year. They often persist through much of the first quarter of that year before decaying.

“Severe droughts and devastating flooding being experienced throughout the tropics and sub-tropical zones bear the hallmarks of this El Niño, which is the strongest for more than 15 years,” said WMO Secretary-General Michel Jarraud in the statement.

Jarraud noted that the WMO is better prepared for this event than it has ever been in the past. On the basis of advice from the WMO’s National Meteorological and Hydrological Services, the “worst affected countries are planning for El Niño and its impacts on sectors like agriculture, fisheries, water and health, and implementing disaster management campaigns to save lives and minimize economic damage and disruption,” Jarraud said.

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WMO released its update on the eve of an international El Niño Conference in New York, of which WMO is a major co-sponsor, to increase scientific understanding of this event as well as its impacts, and help boost resilience to anticipated global socio-economic shocks. The conference will provide an overview of the 2015 El Niño event and its potential impacts; explore the connection between the current El Niño and global change; foster dialogue between climate scientists and development practitioners to strengthen action for climate resilience and sustainable development; and examine the progress, and lessons learned, over last 20 years in international, national and regional climate services, with a focus on El Niño.

“Our scientific understanding of El Niño has increased greatly in recent years,” Jarraud noted. “However, this event is playing out in uncharted territory. Our planet has altered dramatically because of climate change, the general trend towards a warmer global ocean, the loss of Arctic sea ice and of over a million square km of summer snow cover in the northern hemisphere. So this naturally occurring El Niño event and human induced climate change may interact and modify each other in ways which we have never before experienced.”

Jarraud noted that even before the onset of El Niño, global average surface temperatures had reached new records. “El Niño is turning up the heat even further,” he said.

The ongoing El Niño has already been associated with a number of major impacts, the WMO noted. These include coral bleaching, as record ocean temperatures, caused in part by El Niño, have contributed to a major coral bleaching event. The WMO even reported that the National Oceanic and Atmospheric Administration estimates that by the end of 2015, almost 95% of coral reefs in the United States will have been exposed to ocean conditions that can cause corals to bleach.

The ongoing El Niño has also contributed to a very active tropical cyclone season in the Western North Pacific and Eastern North Pacific basins. Hurricane Patricia, which made landfall in Mexico on Oct. 24, was reportedly the most intense tropical cyclone in the western hemisphere. El Niño tends to reduce hurricane activity in the Atlantic and around Australia.