Earth experiencing warmest year on record – again, scientists say

For the second year in a row, climate scientists are "virtually certain" that 2024 will be another record-warm year for Earth.

The European Union’s Copernicus Climate Change Service announced October was the second-warmest October globally after last year, running about 0.8 degrees Celsius (1.44 degrees Fahrenheit) above the 30-year average for October. These averages are based on the ERA5 dataset, which uses billions of measurements taken by spacecraft, ships, aircraft and weather stations around the world.

For the past 10 months, the average global temperature anomaly has been 0.71 degrees Celsius (1.28 degrees Fahrenheit) above the 30-year average, the highest on record for this period. 

Copernicus said October virtually seals the deal that 2024 will be the warmest on record. To not hit this climate record, above-average temperatures would have to be non-existent globally for the remainder of the year. 

The latest climate data comes as the 2024 United Nations Climate Change Conference, or COP29, is set to begin on Monday in Baku, Azerbaijan.

"After 10 months of 2024, it is now virtually certain that 2024 will be the warmest year on record and the first year of more than 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels according to the ERA5 dataset," Deputy Director of the Copernicus Climate Change Service Samantha Burgess said. "This marks a new milestone in global temperature records and should serve as a catalyst to raise ambition for the upcoming Climate Change Conference, COP29."

Climate scientists are not surprised by the record warmth. After experiencing the warmest January, NOAA said there was a 99% chance 2024 would once again hit the hot milestone like 2023. This year also broke 2023's hottest day on record when the average planetary temperature reached 17.15 degrees Celsius (62.87 degrees Fahrenheit) on July 22.

The Copernicus Climate Change Service noted above-average temperatures across most of Europe and northern Canada and well-above-average temperatures over the central and western U.S., northern Tibet, Japan and Australia. 

Copernicus also monitors sea-surface temperatures, which remain "unusually high over many regions," according to the climate group. October's average sea-surface temperature was 20.86 degrees Celsius (69.54 degrees Fahrenheit), the second highest on record for the month, just 0.10 degrees Celsius (0.18 degrees Fahrenheit) below last year.