2024 breaches 1.5°C warming threshold: What it means
What's the story
2024 has officially become the first year to exceed the global warming threshold of 1.5 degrees Celsius, data from the Copernicus Climate Change Service (CCCS) revealed.
The CCCS recorded an annual average temperature increase of 1.6 degrees Celsius above pre-industrial levels for the year.
The World Meteorological Organization (WMO) also confirmed the finding, using six different datasets to establish that 2024 was around 1.55 degrees Celsius warmer than pre-industrial times.
Record warmth
2024: Warmest year on record, but not Paris Agreement breach
All six datasets used by the WMO flagged 2024 as the warmest year on record. However, not all of them noted a temperature rise beyond the 1.5 degrees Celsius threshold.
The European Centre for Medium-Range Weather Forecasting (ECMWF) explained that "one or two years that exceed 1.5 degrees Celsius above pre-industrial level does not imply that the Paris Agreement has been breached."
Unusual warmth
Record-breaking temperatures and potential contributing factors
The years 2023 and 2024 were exceptionally warm, with many record-breaking temperature events.
Every month since July 2023, barring July 2024, witnessed a warming of over 1.5 degrees Celsius above pre-industrial averages.
An El Nino event during the years added to the warmth but was weaker than the strong El Nino of 2015-2016.
Other possible contributors to this unusual warming include "unprecedented" El Nino-like systems in several ocean regions and an underwater volcanic eruption near Tonga in January 2022.
Future outlook
2025 temperature forecast and beyond
While the warming trends of 2023 and 2024 are unlikely to continue into 2025, temperatures will likely remain within recent ranges of 1.1 to 1.4 degrees Celsius above pre-industrial levels.
The UK Met Office forecasts 2025 as the third warmest year on record after 2024 and 2023.
A WMO report indicates annual average temperatures may hit up to 1.9 degrees Celsius above pre-industrial levels before 2028, with a five-year average exceeding the threshold having over 50 percent probability by then.