Earth cooled slightly last year - but it still was the fourth warmest on record, a new analysis shows.
With the partial U.S. government shutdown, federal agency calculations for last year's temperatures are delayed.
But independent scientists at Berkeley Earth calculate that last year's average temperature was 58.93 degrees (14.96 degrees Celsius), 1.39 degrees (0.77 degrees Celsius) warmer than the average from 1951 to 1980 and about 2.09 degrees (1.16 degrees Celsius) warmer than pre-industrial times.
'Global mean temperature in 2018 was colder than 2015, 2016, and 2017, but warmer than every previously observed year prior to 2015,' the researchers said.
'Consequently, 2016 remains the warmest year in the period of historical observations.
'The slight decline in 2018 is likely to reflect short-term natural variability, but the overall pattern remains consistent with a long-term trend towards global warming.'
It's likely other temperature measuring groups will agree on 2018's ranking since they had it at fourth hottest through November, said Berkeley Earth climate scientist Zeke Hausfather.
The Japanese Meteorological Agency has already calculated it at fourth.
Hausfather said it would be foolish to call last year's slight dip a cooling trend.
'The long term is stunningly clear,' he said.
Record-keeping started in 1850.
Only 2016, 2017 and 2015 were warmer than last year, with only small differences among them.
'Though 2018 only ranks fourth overall, 2015 through 2018 still stand out as a period of significant warmth well above all previous years since 1850,' the researchers added.
'This reflects the long-term trend towards global warming.
'Though 2018 is slightly cooler than the immediately preceding years, its temperature remains consistent with the long-term warming trend.'
Pennsylvania State University climate scientist, who wasn't part of the Berkeley Earth team, said the fact that nearly every year recently is in the top five or top 10 hottest years is 'clear evidence of human-caused warming on this planet.'
Last year, 29 countries, including much of Central Europe, and Antarctica had record hot years, Hausfather said.
Every month in 2018 was at least 0.67 °C warmer than the 1951 to 1980 average, but no month in 2018 set a new monthly record for the globe, the new figures show.
In the maps below, the persistent heat anomaly over Europe is visible through the latter portion of the year.
A prolonged period of winter warmth in Antarctica is also visible.
In the oceans, the weak La Niña pattern is visible in the Eastern Equatorial Pacific during the early months of 2018.
Though a transition to weak El Niño conditions for the end of 2018, the temperature patterns in the Pacific at the end of the year remain weak and unconsolidated.