MINNEAPOLIS (WCCO) — The National Oceanic and Atmospheric Administration (NOAA) announced that 2016 was the second-hottest year on record in the U.S. And worldwide, 2016 is poised to go down as the hottest year on record.
One of the world’s leading climate scientists put the numbers in perspective.
Dr. Kevin Trenberth won the Nobel Peace Prize for his work explaining climate change. So when he, and others, say the periodic warming of the Pacific Ocean — known as El Nino — is the smoking gun that accounts for the last two years being the warmest on record, it’s important.
“In the second half of the El Nino heat comes out of the ocean into the atmosphere, and that contributes, especially, to the global warming,” he said.
Trenberth says there’s something else going on.
“The oceans have been warming more than thought, and so this is the memory of past global warming,” he said. “Without the El Nino, more than 1 degree Fahrenheit above values prior to 1970, or thereabouts.”
El Nino tends to simply add to the warming that’s already occurring. The opposite pattern, called La Nina, can temporarily subtract, meaning global average temperatures tend to change like, according to Trenberth, “a staircase rather than a steady rise. And, at the moment, we’ve sort of taken a step up. And we’ve stalled a little bit, and may go down a little bit, but we won’t go back down to the previous levels that we’ve seen earlier, back in say the 1990s or earlier.
“There are other indicators — like sea level rise, and the heat content in the oceans — that are much more steadily increasing that show that global warming is clearly occurring, and we better watch out because it has consequences,” he continued.
Web Extra: Full Interview With Dr. Kevin Trenberth
He also told WCCO’s Mike Augustyniak that climate change could likely be a factor in it being the Twin Cities’ wettest year on record.
“If the atmosphere is running warmer, there tends to be more moisture in it, and it rains harder,” he said.
Trenberth says 2017 will likely be a cooler year for the earth, compared to 2016, because the El Nino pattern has ended.
The World Meteorological Organization is expected to release worldwide figures on 2016 later this month.