EarthSky, January 2024
“Global temperatures reached exceptionally high levels in 2023,” said a new report out on January 9, 2024. The data are from Copernicus, the European Union space program’s Earth-observing program. We overtook the previous hottest year on record, 2016, by a large margin. We also had daily global temperature averages that surpassed pre-industrial levels by more than 2 degrees Celsius [3.6°F] for the first time. And, in 2023, Earth had its hottest month on record. What drove the unprecedented heat? A combination of greenhouse gasses, El Niño and other natural variations.
2023 was the hottest year on record, with data going back to 1850. Last year was the first time that every day within the year exceeded 1 C above the 1850-1900 pre-industrial level. And November 17 and 18 were the first time the average global temperature exceeded 2 C above pre-industrial temps.
Why do we compare temperatures now to the pre-industrial level? This is the level discussed in the Paris Agreement. In the Paris Agreement, 196 parties agreed to limit temperature increases to well below 2 C above pre-industrial levels and to aim for 1.5 C. So why is 2 C the magic number? As Maria Ivanova at Northeastern University explained, “at two degrees we see dramatic alterations to the ability of the Earth’s system to maintain the conditions that allow for human life and indeed other species’ life.”