Global average temperatures in 2025 eased compared with 2024 because of a returning La Niña pattern, but new data from the Copernicus climate service and the UK Met Office show 2025 remained far warmer than a decade ago and continued the three-year run of record-high global warmth. Scientists warn that the planet is approaching the long-term 1.5°C Paris threshold — Copernicus and the Met Office estimate 2025 averaged more than 1.4°C above late-19th-century “pre-industrial” levels. Extreme events such as the January 2025 California fires and Hurricane Melissa in October continued to reflect climate-driven risk, illustrating that temporary natural cooling has not pushed global temperatures back to earlier levels. Experts say further records and worsening extremes are likely unless greenhouse-gas emissions fall sharply.
Key takeaways
- Copernicus and the Met Office report 2025 as more than 1.4°C above pre-industrial baseline; the figure is slightly variable by dataset but consistent in trend.
- The years 2023–2025 form the warmest three-year period on record, with 2024 boosted by El Niño and 2025 moderated by La Niña.
- Natural variability (El Niño/La Niña) explains year-to-year differences; La Niña suppressed 2025 relative to 2024 but did not return temperatures to earlier-decade levels.
- Extreme weather continued in 2025: January’s California fires were among the costliest US weather disasters, and Hurricane Melissa caused mass flooding in Haiti and destruction elsewhere in the Caribbean.
- Scientists warn the world is edging toward breaching the Paris Agreement goal of limiting warming to 1.5°C, likely later this decade if emissions continue at current rates.
- Some researchers note unexpectedly rapid warming at the high end of projections and are investigating possible contributions from changes in clouds or aerosols.
- Attribution of specific events to climate change remains nuanced — studies indicate climate influence on intensity or likelihood but precise quantification varies by event.
Background
The international goal to limit warming to 1.5°C above pre-industrial levels was adopted by nearly 200 countries in the 2015 Paris Agreement. That threshold is intended to reduce the most serious risks of climate impacts; scientists treat it as a long-term benchmark rather than a single-year cutoff. Global temperature records are assembled by several groups; small methodological differences in defining the pre-industrial baseline or coverage produce slightly different anomaly numbers, but all show a clear multi-decadal warming trend.
Natural climate variability — chiefly the El Niño–Southern Oscillation, which alternates between El Niño and La Niña phases — modulates global annual temperatures. El Niño years typically push global averages higher; La Niña years tend to be cooler. On top of that natural variability sits the persistent warming from rising greenhouse-gas concentrations, which raises the baseline and increases the likelihood and severity of heat extremes, heavy rainfall and some storm intensities.
Main event
In releases this week, the Copernicus Climate Change Service and the Met Office presented independently produced global temperature estimates showing 2025 fell short of 2024’s peak but remained well above temperatures seen a decade ago. Both agencies reported a global average exceeding 1.4°C above the late-1800s benchmark. The agencies noted small methodological differences, but their conclusions on long-term warming and recent extreme warmth align.
Scientists pointed to La Niña as the principal reason 2025 did not surpass 2024: the cool phase of the Pacific cycle reduced global-average temperatures relative to 2024’s El Niño-enhanced peak. Even so, researchers described the persistence of high temperatures during a La Niña year as concerning, given the multi-year context of accelerating baseline warming from human emissions.
Events during 2025 underlined the human and economic stakes. January’s California wildfires were among the most expensive weather-related disasters recorded in the United States, while Hurricane Melissa in October produced catastrophic flooding in Haiti and severe impacts across parts of the Caribbean. Early attribution studies and event investigations point to climate-driven increases in intensity for some events, although each case requires careful analysis.
Analysis & implications
The near-term interplay of natural variability and long-term forcing can produce years that are relatively warmer or cooler, but the upward trend in baseline global temperature is driven by cumulative greenhouse-gas emissions. Scientists warn that the progression seen across 2023–2025 moves the world closer to the 1.5°C threshold and increases the chance that consecutive new records will be set in coming years, particularly if El Niño returns.
There is active debate about whether the unusually large jump in 2023 and the continued high values through 2025 signal changes beyond known drivers. Hypotheses under investigation include alterations in cloud reflectivity or reductions in aerosol cooling — factors that would change how much solar radiation is reflected back to space. Those ideas remain research topics and are not yet confirmed as primary causes.
Policy implications are straightforward in direction though complex in practice: limiting future warming requires rapid, sustained reductions in carbon and other greenhouse-gas emissions, alongside measures to increase resilience. Scientists emphasize that mitigation (cutting emissions) can change long-term outcomes, while adaptation can reduce immediate harms from heat, storms and floods that are already more likely because of higher temperatures.
Comparison & data
| Year | Context | Principal driver |
|---|---|---|
| 2023 | Marked large jump in global anomalies; part of record-warm run | Long-term warming plus factors under study |
| 2024 | World’s warmest year on record; El Niño contributed | El Niño + background warming |
| 2025 | Cooler than 2024 but still >1.4°C above pre-industrial | La Niña moderated temperatures atop high baseline |
The table above frames 2023–2025 without assigning precise monthly anomalies beyond the published Copernicus/Met Office summary that 2025 exceeded 1.4°C above pre-industrial. Differences among datasets stem primarily from how the classical pre-industrial period is defined and the methods used to fill gaps in coverage; these methodological choices do not alter the underlying conclusion that the planet has warmed substantially.
Reactions & quotes
“If we go twenty years into the future and we look back at this period of the mid-2020s, we will see these years as relatively cool.”
Dr Samantha Burgess, Deputy Director, Copernicus
Context: Burgess used this framing to underline how the current mid-2020s warmth may appear modest compared with decades ahead if emissions continue unabated.
“We understand very well that if we continue to pump greenhouse gases into the atmosphere…the planet responds by warming.”
Prof Rowan Sutton, Director, Met Office Hadley Centre
Context: Sutton stressed the causal link between cumulative emissions and long-term temperature rise and called attention to both mitigation and adaptation options.
“The persistence of high temperatures in a La Niña year is a little worrying.”
Dr Zeke Hausfather, Climate Scientist, Berkeley Earth
Context: Hausfather highlighted that sustained warmth even during a cooling phase suggests there are aspects of recent change scientists are still probing.
Unconfirmed
- Whether cloud changes or reduced aerosol cooling were significant contributors to the large 2023 temperature jump remains under investigation and is not yet established.
- It is not yet confirmed whether the three-year run of extreme warmth represents a durable change in the warming rate beyond expected variability; more data and analysis are required.
- Attribution studies for individual 2025 extreme events continue; for some incidents the degree to which climate change altered likelihood or intensity is still being quantified.
Bottom line
2025 shows that natural variability can temporarily moderate global averages, but it has not reversed the upward trajectory driven by human emissions. With Copernicus and the Met Office placing 2025 more than 1.4°C above pre-industrial levels and the three-year block 2023–2025 as the warmest on record, the planet is edging closer to the 1.5°C benchmark agreed in Paris.
That proximity increases the odds of further record-breaking years in the near future, particularly if El Niño re-emerges. The policy choice remains clear: aggressive emissions cuts can alter the long-term path, while adaptation will be essential to reduce harm from the heightened extremes already occurring.
Sources
- BBC News (news report summarizing Copernicus and Met Office findings)
- Copernicus Climate Change Service (official climate monitoring service)
- UK Met Office (official national meteorological service)
- Berkeley Earth (independent climate research organization)