Boston: For the first time in 17 months, the world didn’t set a new record for temperatures.
Thank El Nino. This phenomenon, marked by warmer-than-normal temperatures across the equatorial Pacific, faded in June and is — at least in part — the reason the world wasn’t as hot as it could’ve been last month, according to the US National Centers for Environmental Information.
“The cooling ocean temperatures in the equatorial Pacific definitely had an impact on this month’s global temperature,” said Jessica Blunden, a climatologist with the agency in Asheville, North Carolina. “This is not surprising, but rather what we expect to see a few months after a warm-phase El Nino ends.”
With temperatures on the rise due to climate change, six of the world’s seven warmest years have occurred since 2009. However, El Ninos can make that worse. Many climatologists describe it as a person riding an escalator.
“The underlying temperature will always continue to increase, like going up an escalator,” Blunden said. “El Nino, record warmth, is when you’re standing on your toes on the ride.”
Since El Nino ended in June, the equatorial Pacific has cooled and could even drift into a La Nina, according to the US Climate Prediction Center. La Nina is when the surface of the ocean is below normal.
While this has been enough to finally break the streak of record warm months, it might not keep 2016 from becoming the third year in a row to set a new global high temperature. September was, after all, still the second hottest on record behind 2015.
If readings for October, November and December just match 21st-century averages, the year will set a new record, according to projections by the National Centers for Environmental Information.
“It is likely 2016 will become the warmest year in the 137-year record,” Blunden said.