2018 was hotter than any year in the 19th century. It was hotter than any year in the 20th century. It was hotter than any year in the first decade of this century. In fact, with only three exceptions, it was the hottest year on Earth since 1850.
Those three exceptions: 2018 was slightly cooler than 2015, 2016, and 2017. The past four years, in other words, have been the four hottest years ever reliably measured.
That’s according to Berkeley Earth, a nonprofit research group that published its annual temperature analysis on Thursday. The new finding “remains consistent with a long-term trend toward global warming,” the report says.
Berkeley Earth is a respected scientific organization, but it’s unusual that this news should come from it alone. Normally, Americans hear about these milestones from their own government. NASA and the National Oceanic and Atmospheric Administration were both due to publish their version of this analysis last week, on January 17. The United Kingdom’s Met Office and Berkeley Earth also planned to release their own findings that day.
But it was not to be. The ongoing federal shutdown has indefinitely delayed the NASA and NOAA reports, so Berkeley Earth decided to go ahead with its report. “We actually finished our analysis last week, but held off releasing it in the hope that things would be resolved,” said Zeke Hausfather, an analyst for the group, in an email. “But at this point it is clear that nothing will happen soon.”