The World Meteorological Organization (WMO) announced yesterday that the powerful 2015-2016 El Niño has passed its peak but will continue influencing weather across the world. It is expected to disappear by the second quarter of 2016. According to measurements, the tropical Pacific Ocean showed sea surface temperatures (SST) were more than 2 degrees Celsius above normal by mid-December 2015. Since recordkeeping began, this El Niño is considered one of the strongest.
And while some scientists are suggesting atmospheric global warming made this El Niño worse, others say this El Niño magnified global warming, making it appear worse. One such scientist is Creighton University Professor Emeritus Dr. Art Douglas, who says this El Niño, while very big, was “comparable to others 100 to 120 years ago. Secondly, when we actually look at the graph of water temperatures off the coast of Washington, Oregon, all the way down to off of Chile.
“They were very steady from about 1976 to 2013 — meaning there was not much variable other than every other year may have been warm or cool,” he added. Dr. Douglas was speaking at the annual Pacific Northwest Farm Forum that had just wrapped up. He says this means “there was not much variable other than every other year may have been warm or cool. But now with El Nino this thing went way up went way up — as I said 8/10s of a degree centigrade.”
Douglas says those reports claiming that global warming “put an extra oomph” into this El Niño and making it stronger have got it backwards. He says it is the “other way around and that this El Niño — called a Mega El Niño — all it did was maybe create the global warming effect to appear to be the main cause — but it’s not.” That’s similar to WMO Secretary General Petteri Taalas’ comment that this El Niño event “caused extreme weather in countries on all continents and helped fuel record global heat in 2015.”
Taalas also says that 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.” It has also caused torrential rains and flooding in parts of South America and East Africa. This has lead to an uptick in the Zika virus, which is spread by mosquitoes that require clean water to lay their eggs.
While it’s still too early to say whether this El Niño will morph into a La Niña, previous El Niños of this magnitude were followed by La Niñas. La Niñas are notable because SSTs become colder-than-normal in the same region, by 3 to 5 degrees Celsius, and this has ramifications on our climate and Atlantic hurricane season. The reason many scientists believe this flip will occur is that since 1950, 11 of the last 15 strong El Niños were immediately followed by equally strong La Niñas. The WMO says it’s still too early to say if this swing will occur.
The WMO update says that models show the SSTs will return to a “neutral state during the second quarter of 2016 and that “El Niño and La Niña are not the only factors that drive global climate patterns.” The state of the Indian Ocean (the Indian Ocean Dipole), or the Tropical Atlantic Sea Surface Temperature, are also capable of affecting the climate in the adjacent land areas.”
They also say that the Arctic and North Atlantic Oscillations can affect winter conditions in the Northern hemisphere. El Niño and La Niña are part of the broader El Niño–Southern Oscillation or ENSO.