2022 was the 5th or 6th warmest year on record: US government agencies

Earth's fever persisted last year. It didn't spike to a record high, but 2022 still made it to the top five or six warmest on record, government agencies reported Thursday.

The U.S. National Oceanic and Atmospheric Administration (NOAA) found that 2022's global average temperature was 14.76 degrees Celsius (58.55 degrees Fahrenheit), ranking sixth hottest on record.

NOAA doesn't include the polar regions because of data concerns, but soon will.

If the Arctic - which is warming three to four times faster than the rest of the world - and Antarctic are factored in, NOAA said it would be fifth warmest.

NASA, which has long factored the Arctic in its global calculations, said 2022 is essentially tied for fifth warmest with 2015.

Four other scientific agencies or science groups around the world put the year as either fifth or sixth hottest.

"2022 is another top ten year," says Gavin Schmidt, director of Goddard Institute for Space Studies, NASA.

"It ranks roughly joint fifth with 2015. The warmer years were 2016, 2020, which were joint first and then 2019 and 2017 were quite warm. But it's another top ten year cementing that long term trend that we've been seeing in temperatures certainly since the 1970s and since the late 19th century. It's the eighth year in a row that's more than one degree Celsius above the late 19th century. And so that's that's getting us very close to that 1.5 (degree Celsius) kind of guideline that came out of the Paris Accords."

And that's in spite of a strong La Nina in 2022, a cooling of the equatorial Pacific that slightly reduces global average temperatures.

It's the opposite of an El Nino, a warming of the Pacific, usually peaking in December.

Berkeley Earth, a nonprofit group of independent scientists, said it was the fifth warmest on record and noted that for 28 countries it was the hottest year on record, including China, the United Kingdom, Spain, France, Germany and New Zealand.

"So we're warming at about 0.2 degree Celsius per decade, a little bit more than that. And then the impact of El Nino and La Nina are about a third of that. So you just need to go a third of the decade and the long term trend is going to cancel out the impact of the La Nina. And so we have now a big La Nina year (that) is almost as warm as the 2016 El Nino year, and that was a massive El Nino," says Schmidt.

Last year was slightly toastier than 2021, but overall the science teams say the big issue is that the last eight years, from 2015 on, have been a step above the higher temperatures the globe had been going through.

All eight years are more than 1 degree Celsius (1.8 degrees Fahrenheit) warmer than pre-industrial times, NOAA and NASA say.

Last year was 1.1 degrees Celsius (2 degrees Fahrenheit) warmer than the mid-19th century, NASA says.

Schmidt's role at NASA involves the supervision of temperature data collection to compute annual averages.

"We take weather station records from countries all around the world. We take ocean ship records from all around the world. Ocean buoys, the Argo float network that now tracks what's going on in the ocean. We put these all together. We try and correct for non climatic things like moves of stations from one place to another, changes of instrumentation, changes in methodology. We try to include those things. We try and take into account the uncertainty from the extrapolation and the interpolation between stations and when you put all that together, that's when you get these records that go back at least to the late 19th century," he says.

And this data has a direct correlation with extreme weather events happening all year round.

"We're talking mainly about the global mean, but nobody lives in the global mean, so all of the things that are happening the heat waves in Europe, the fires in Europe, the warmest year in the UK, the flooding in Pakistan and elsewhere, the heat waves again in the Pacific Northwest, the fires, all of these things are associated with local temperatures," says Schmidt.

The La Nina is in its third consecutive year.

Schmidt calculated that last year, the La Nina cooled the overall temperature by about 0.06 degrees Celsius (0.01 Fahrenheit) and that last year was the hottest La Nina year on record.

"So we're anticipating that 2023 will be warmer than 2022, both because the La Nina intensity will be less, but also because you've got another year of the long term trends," says Shmidt.

Schmidt says there are hints of an acceleration of warming but the data isn't quite solid enough to be sure. But the overall trend of warming is rock solid.

Schmidt's predecessor, climate scientist James Hansen, testified about worsening warming in 1988.

That year would go on to be the record warmest at the time.

Now, 1988 is the 28th hottest year on record.