Strongest El Nino in 15 years playing out in 'uncharted territory,' WMO says

The El Ninoweather pattern, aphenomenon associated with extreme droughts, storms and floods,is expected to strengthen before the end of the year and becomeone of the strongest on record, the U.N. weather agency says.

The World Meteorological Organization (WMO) said MondayElNino was already "strong and mature" and the biggest in more than 15 years.

The phenomenon is driven by warm surface water in theeastern Pacific Ocean, and this time three-month averages willpeak at more than 2 degrees Celsius above normal, putting thisEl Ninoin the same league as those seen in 1972-73, 1982-83 and1997-98, the WMO said.

"Right now we say we think it's really going to be one ofthe three strongest ones, it may be one of the two, that wedon't know yet. But definitely it's already a very strong one,"WMO Secretary-General Michel Jarraud told a news conference.

He said the world was better prepared for this El Ninothanbefore, and the worst-affected countries were planning for theimpact on agriculture, fisheries, water and health, andimplementing disaster management campaigns to save lives andminimise economic damage.

"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 ofArctic sea ice and of over a million squarekilometresof summer snow coverin the northern hemisphere," Jarraud said.

"So this naturally occurring El Ninoevent and human-inducedclimate change may interact and modify each other in ways whichwe have never before experienced. Even before the onset of ElNino, global average surface temperatures had reached newrecords. El Ninois turning up the heat even further."

• Temperatures in 2015 on track to be record 1 degree C hotter

Heatwaves would be hotter and more frequent and more placeswould be at risk of flooding, Jarraud said, while the mostsevere storms equivalent to category 4 and 5 hurricanes would occur more often.

In addition, rising sea levels mean tsunamis and stormsurges will have greater reach and inflict more damage when theyhit land, Jarraud said.

El Ninoconditions normally reach maximum strength betweenOctober and January, then persist through much of the firstquarter.

"We anticipate that the El Ninowill peak over the next fewmonths and will progressively when we go towards May, June,July, when we go to the second quarter of next year will gomore towards neutral conditions," Jarraud said.