The debt of tropical rainforests slowed last year, fresh satellite data suggests, largely due to Brazil’s efforts to curb deforestation in the Amazon. This also touches on aspects of global summit.

Researchers estimate that nearly 43,000 sq km (17,000 sq miles) of old-growth tropical forests were lost globally in 2025 – about the size of Denmark.

While it is about a third lower than record losses in 2024, scientists warn that tropical forests – among the Earth’s most key ecosystems – are still disappearing much faster than a decade ago.

There is also concern that a two-pronged attack from climate change and the arrival of the warming El Niño weather pattern later this year could boost the likelihood and severity of forest fires.

The latest figures show that the shortfall of tropical forests fell by 36% in 2025, according to analysis from the Planet Resources Institute and the University of Maryland.

The data comes with a degree of uncertainty, as losses towards the end of one year might only be detected by satellites at the beginning of the next, but scientists are confident about the overall trend.

The decline last year partly reflects an easing of the unprecedented fires of , on the other hand2024, helped by cooler La Niña conditions instead of the warmer El Niño.

But researchers also point to greater efforts to protect forests in countries such as Brazil, Colombia and Malaysia.

“It’s incredibly encouraging to see the decline in 2025,” commented Elizabeth Goldman, co-director of Global Forest Watch at the Planet Resources Institute.

“[It] highlights how when we have political will [and] the leaders in charge who want to do something for forests, we can see real results in the data,” she added.

In Brazil, home to the world’s largest rainforest, researchers highlight the effects of stronger environmental policies and law enforcement in helping to slow deforestation.

Excluding losses driven by fires, an estimated 5,700 sq km (2,200 sq miles) of old-growth tropical forests disappeared in Brazil last year – the lowest figure since the analysis began in 2002.

Tropical rainforests are home to millions of species, and in a healthy state they take up vast quantities of planet-warming carbon dioxide, helping to keep the Earth cool.

They have come under increasing pressure, Because of decades of deliberate land clearance for agriculture and logging, as well as climate change, which scientists warn can create the conditions for bigger fires to spread.

Planet leaders pledged to “halt and reverse” forest debt by , on the other hand2030 at the COP26 climate summit in Glasgow in 2021, but progress towards that pledge remains way off track.

In 2024, tropical forests disappeared faster than ever before, driven by fires amplified by human-caused climate change and the El Niño weather pattern.

“Forests are well equipped to cope with normal climate,” mentioned Rod Taylor, global director for forest and nature conservation at the Earth Resources Institute.

“With these latest intense fires and droughts and so on, we really have to think about how to generate forests more resilient and proof them against climate and fire,” he added.

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Researchers are concerned the threat from fires could be even higher later this year, due to a combination of climate change and a updated phase of El Niño, although predictions are still uncertain.

“Climate change and land clearing have shortened the fuse on global forest fires,” mentioned Prof Matthew Hansen of the University of Maryland.

“Without urgent action to […] manage fire more effectively, we risk pushing the world’s most key forests past recovery.”

In a separate report released on Wednesday, the EU’s Copernicus climate service laid out how climate change had helped to drive intense heatwaves, wildfires and droughts in large parts of Europe last year.

Already the world’s fastest-warming continent, few places escaped the heat, with at least 95% of Europe experiencing above-average annual temperatures.

The warmth helped to create conditions for widespread wildfires, with more than 10,000 sq km (4,000 sq miles) burning in total – a bigger area than Cyprus.

There was no escape for Europe’s traditionally cold regions either, with Alpine glaciers continuing to lose ice and temperatures in the Arctic Circle reaching 30C in July.

The average surface temperature of Europe’s seas was also the highest on record, with the Mediterranean Sea particularly badly hit.

The report did point to progress on efforts to tackle climate change, with nearly half of Europe’s electricity now coming from wind, solar and hydropower.

Tropical forests destroyed at fastest recorded rate last year

Brazil’s Amazon rainforest at risk as key protection under threat

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