2022 was once again one of the warmest years on record

Enlarge / Average 2022 temperatures compared to the average of 1991-2020. (credit: NOAA)

They say history repeats, but usually they don’t mean it quite this literally. The global average surface temperature in 2021 ended up ranking fifth warmest or sixth warmest, depending on the dataset. We now have the tally for 2022—and it’s the new fifth or sixth warmest, depending on the dataset.

Each year in mid-January, various centers that manage global temperature datasets release their results for the previous year. Because each group pulls from a slightly different collection of weather stations and uses a slightly different calculation process, they don’t get exactly the same numbers. The big picture is identical, but since just 0.01°C can separate years in the ranking, those small differences can alter the order.

In the European Copernicus ECMWF dataset and the Berkeley Earth dataset, 2022 is the fifth warmest in the global instrumental record going back to the mid-to-late 1800s. Meanwhile, the National Oceanic and Atmospheric Administration and UK Met Office datasets pin it at No. 6, just below 2015 instead of just above it. NASA’s dataset has it tied with 2015 for fifth warmest. The total heat energy in the ocean, on the other hand, reached a new record. Over 90 percent of the total heat trapped by greenhouse gas emissions has gone into the oceans, and this value varies less from year to year.