A four-day ‘megafire’ last year across parts of the Highlands and Moray unleashed nearly a year of fire emissions, according to a new analysis.
The study, published in Nature Geoscience, found the 2025 Dava Moor fire torched as much acreage as usually burns in an entire year in the U.K, and classed it as Britain’s first ‘megafire’.
Researchers also said it released carbon equivalent to 85% of the average annual emissions from fires across the U.K from 2001 to 2021.
It also found almost 85% of the fire’s carbon emissions came not from burning trees or brush, but from burning peat.
The megafire is an emerging concept first used in the U.S, which refers to the size and scale of a wildfire.
Lead study author Johanna Schoenecker said definitions vary, but a megafire is typically classed as larger than 10,000 hectares, or roughly 25,000 acres, in an interview.
Schoenecker added the Dava Moor fire burned quickly and severely, blazing through mainly heathland and bogs, and only small patches of forest.
She said peatlands are slow to build up and can take many hundreds of years to sequester large amounts of carbon.
Schoenecker added the Dava Moor fire burned into the peat, releasing significant amounts of carbon, which was not immediately apparent from the surface damage.
“Peat can build up over centuries or even millennia, but if it is dry enough to burn it will release carbon in a relatively short amount of time, making it irrecoverable in our lifetime,” she told me.
Another of the report’s lead author’s, Adam Pellegrini, an assistant professor of Earth System Science at the Stanford Doerr School of Sustainability, said carbon lost in a peatland fire is considered irrecoverable because of the massive time scales needed to recover and reaccumulate it.
Pellegrini added climate change and rising temperatures will make the process of restoring peatland harder, because heat increases the atmospheric demand for water, meaning it is more susceptible to fire.
He said shifts in rainfall patterns can sometimes counteract warmer, drier conditions, but he added current forecasts for the U.K. and Europe highlight the impact of rising temperatures, and the likelihood of more wildfires.
“We have the environmental conditions there, being hot and dry, but any fire spread will depend on meteorological conditions like wind, how much of it burns.
“Up in Scotland, there’s a large swath of moorland and peatland which are sparsely populated, and so that’s one reason why I think those areas could be more prone to these megafires, but it’s also important to think about the infrastructure and who has the firefighting capacity up there as well.
“I’ve been to a few private game reserves up in Scotland, namely near the Cairngorms, and they’re incredibly sophisticated in how they fight wildfires.”
In separate news, the rural business organisation Scottish Land and Estates (SLE) has warned public policy in the U.K. has not kept pace with the increasing risk of high-intensity, large-scale and more frequent wildfires.
In its response to a parliamentary committee, it has called for a coherent strategic framework covering wildfire preparation, risk reduction, funding and operational plans.
Ross Ewing, director of moorland and strategic projects for SLE, said wildfires can no longer be treated as an isolated issue, which UK fire services can manage on their own, in a statement.
Ewing said it is now a land management, climate resilience, public safety and rural economy issue, that demands a stronger national response rooted in prevention as well as response.