Earth Records Third-Hottest September as Global Temperatures Remain Near Historic Highs

Scientists anticipate that 2025 will rank as the third-warmest year, following the record-breaking temperatures of 2024 and 2023.

The Copernicus Climate Change Service announced Thursday that our planet has just experienced its third-hottest September on record, with global average temperatures remaining near historic maximums for yet another month.

September did not surpass the record established in 2023 and was only slightly cooler than the corresponding period last year, according to the EU's climate monitoring service.

"The global temperature situation remains largely unchanged, with persistently elevated land and sea surface temperatures reflecting the ongoing impact of greenhouse gas accumulation in the atmosphere," explained Samantha Burgess, strategic climate lead at Copernicus.

September registered 1.47C above the 1850-1900 baseline, which is used as the reference for pre-industrial conditions before human activities began significantly altering the climate.

The September 2025 Climate Bulletin from Copernicus reports the third-warmest September globally, with an average surface air temperature measuring 16.11°C — 1.47°C above estimated pre-industrial levels. Global average sea surface temperature reached 20.72°C, the third-highest ever recorded for September.

These incremental increases may seem minimal. However, scientists emphasize that every fraction of a degree of additional warming further destabilizes our planet, heightening the risk of extreme weather events and triggering destructive climate tipping points.

Global temperatures have been consistently rising due to humanity's greenhouse gas emissions, primarily from fossil fuels consumed on an enormous scale since the industrial revolution.

Scientists predict that 2025 will be the third-hottest year after 2024 and 2023, with recent months tracking just below the records established during this extraordinary period.

Nations confront this reality as they prepare to gather in Brazil next month for the annual UN climate negotiations aimed at addressing the collective response to global warming.

Major economies are not reducing emissions rapidly enough to avoid the worst impacts of climate change, and many continue to approve new oil, coal, and gas projects.

Copernicus utilizes billions of measurements from satellites, ships, aircraft, and weather stations to inform its climate calculations.

While their records extend back to 1940, other climate data sources—such as ice cores, tree rings, and coral skeletons—allow scientists to broaden their conclusions using evidence from much further in the past.

Scientists indicate that the current period is likely the warmest the Earth has experienced in the last 125,000 years.