For the first time ever, average global temperatures will rise approximately 1.02°C above pre-industrial levels in a single year, the U.K.'s Met Office climate and meteorological agency reported.
This year's El Nino, characterized by unusually warm temperatures in the equatorial pacific, helped push temperature levels to the new record.
But of course they were bolstered by the continued trend of human-caused global warming.
"We've had similar natural events in the past, yet this is the first time we're set to reach the 1°C marker and it's clear that it is human influence driving our modern climate into uncharted territory," Stephen Belcher, director of the Met's Hadley Centre for Climate Science and Services, said in the agency's release.
The agency has also previously reported that there was 97% certainty 2015 would be the hottest on record.
Peter Scott, head of the Met's climate monitoring and attribution office, said this likely won't be the last time the earth surpasses the 1-degree threshold .
"As the world continues to warm in the coming decades, however, we will see more and more years passing the 1 degree marker—eventually it will become the norm," he said.
While the agency suggests it is still possible to limit warming to 2 °C above preindustrial levels, that will require greenhouse gas emissions to peak soon.
The United Nations has set 2°C as the temperature level beyond which most the Earth cannot avoid catastrophic changes to the natural world.
Rob covers business, economics and the environment for Fusion. He previously worked at Business Insider. He grew up in Chicago.