The World Meteorological Organization says it expects the current El Nino to be one of the three strongest ever recorded since 1950. The WMO reports the weather phenomenon is continuing to mature and is likely to strengthen further in the next few months.
El Nino results from the complex interaction between the Pacific Ocean and the atmosphere. El Nino years normally are significantly warmer than non El-Nino years, a premise supported by the first 10 months of this year, which were the warmest on record.
Despite this significant warming trend, WMO Secretary-General Michel Jarraud says no link yet has been established between El Nino and climate change.
“We are in uncharted territory because some of the impact are interacting with the impact of climate change; but, there is a lot of research going on…But, right at this stage, we cannot say yet whether climate change will mean more frequent or more intense El Ninos,” said Jarraud.
Models suggest the peak three-month average surface water temperatures in the east-central tropical Pacific Ocean will exceed 2 degrees Celsius above average. This would place this El Nino event among the three strongest previous events since 1950.
Jarraud says no two El Ninos are identical, although the exposure of coral reefs to ocean conditions can cause bleaching. He says this can already be seen in the United States and is expected to hit Australia's Great Barrier Reef in early 2016.
He says El Nino also causes extreme weather events, including an increase in tropical cyclones in the Pacific and the opposite effect in the Atlantic, where fewer hurricanes are expected. He says intense flooding will occur in some areas offset by increased drought in others.
For example, he notes in eastern Africa, El Nino is increasing rainfall in the equatorial sector of the Great Horn of Africa and drought conditions in southern Africa.
The 1997-98 El Nino, the strongest to date, led to hundreds of deaths and billions of dollars in economic losses. No one can predict what will happen during the current El Nino season, but, WMO Secretary-General Jarraud says the impact in lost lives and property damage is likely to be much less because of improved forecasting and preparation.