Last year was the fourth-warmest year on record, but prepare for worse to come.
British meteorologists are predicting the next five years will be much hotter, maybe even record-breaking.
Two US agencies, the United Kingdom Met Office and the World Meteorological Organisation analysed global temperatures in slightly different ways, but each came to the same conclusion today: 2018 was the fourth-warmest year on record behind 2016, 2015 and 2017.
The US government's National Oceanic and Atmospheric Administration said 2018's average temperature was 14.69C, which is 0.79C warmer than the 20th century average.
Much of Europe had its warmest years on record. Records go back to 1880.
Nasa and Noaa climate scientists said even though 2018 was a tad cooler than the three previous years that's mostly due to random weather variations.
"Never mind the little wiggles from year to year. The trend is going relentlessly up, and it will continue to do so," Potsdam Institute climate scientist Stefan Rahmstorf said in an email. "Those who live in denial of this fact are in denial of physics."
Using computer simulations, the British weather office forecast s that the next five years will average somewhere between 14.73 to 15.27 C. That would be warmer than the last four years.
Outside scientists, such as Natalie Mahowald of Cornell University, said the forecast is consistent with what researchers know about warming and natural variability.
The obvious long-term trend of steady warming makes it easier to more accurately predict near future warming, said Nasa chief climate scientist Gavin Schmidt.
The US temperature in 2018 was the 14th warmest on average, said Noaa climate monitoring chief Deke Arndt.
Last year was also the third wettest on record in the US. Nine eastern states had their wettest years on record, "an exclamation point on a trend of big rain" in the age of climate change, Arndt said.
There were 14 weather and climate disasters that cost more than US$1 billion, for a total of US$91 billion, Arndt said.