How will climate change impact wildfires in Scotland?

The number of blazes affecting more than 1000 square metres dropped annually from 2017 to 2020 but have started to increase over the past two years, SFRS data revealed.

Experts are expecting the once “lowkey risk” to become much greater over the next couple of decades, warns Guillermo Rein, professor of fire sciences at Imperial College London

“We are all expecting changes in the behaviour of wildfires in Scotland and the UK in general and everybody is expecting more and bigger wildfires,” said Prof Rein.

READ MORE: Wildfires, clegs, ferry disruptions. How climate change is already hitting Highlands

He warned that the UK continues to “respond to surprises” each year but a number of experts have urged for longer-term planning in the fight against the potentially devastating incidents.

Prof Rein said: “What scientists are saying is that the future doesn’t look good, the future looks very concerning.

“I am not saying the next month, or the next year, but in the next several years it is not looking good.

“The resources should not be waiting for the fires to happen, the resources and the training and the awareness and the management of a land should be happening now.”

Outdoor blazes commonly occur in spring in Scotland as old grass and plants like heather dry out after the winter months, providing fuel which burns rapidly after ignition.

Wildfire risk in the country is driven by the atmosphere's capacity to dehydrate Scottish vegetation which is “particularly susceptible” to drying out after periods of less rainfall and high-pressure systems.

Last March firefighters were called to the equivalent of more than two fires a day after the force recorded 65 incidents of blazes spreading to an area larger than 1000 square metres.

It is the third-highest number of callouts recorded between 2017 and 2022, following peaks in May 2017 and April 2019.

Dr Mike Rivington, who researches climate change and land use changes at James Hutton Institute in Aberdeen, said projections indicate that dieback of plants could become more common in the summer too.

“We are seeing some seasonal shift already and, in the future, we're going to see further seasonal shift,” he said.

“The summer will become drier and warmer. That means there will be more evaporation from vegetation is likely to dry out and that will affect fuel load as well.”

Last August saw wildfires soar compared to the month’s average number of blazes over the previous five years - the 14 fires were more than 4 times the average for the summer month.  

In 2022, the East of Scotland experienced the tenth driest in 100 years with the Scottish Environment Protection Agency (SEPA) issuing a number of water abstraction suspensions.

Of the large-scale wildfires experienced during August, 86% took place in areas which were experiencing either moderate or significant water scarcity.  

Dr Rivington said analysis shows that the East of Scotland is likely to be more vulnerable to wildfires in the future due to reduced rainfall.

Rainfall is one of the factors considered by the current system used by the SFRS to predict periods when there is heightened chance of wildfires breaking out which relies heavily on the Canadian Fire Weather Index System.

However, the James Hutton Institute helped lead Scottish Government funded research which found that the Canadian system could miss certain risk as it does not cover “fuel structures”, or vegetation, most likely to ignite in Scotland – heather moorlands.

The system, while one of the most mature in the world, works exceptionally well under forested areas but “our wildfires are shrubland”, Dr Jason Owen said.

READ MORE: Moray wildfire ‘shaping up to be one of largest seen in UK for years’

He added: “If the ground is drier, the plants are drier, the source of ignition could be easier. That’s the sort of things that the models take into account.

“What we need to do is establish where do we find our plant biomass, what species do we have within these areas and how do interact with the climate?

“We need to have a more in-depth knowledge of our biomass in Scotland, both geographically and by species.

Prof Rein said the lack of a true British methodology for quantifying risk in Scotland and other parts of the UK was a “concern”.

However, the path to a Scottish system must first see a decision on “what is valuable” – whether particular natural habitats or our infrastructures, said lecturer in fire investigation at University of Edinburgh Dr Rory Hadden.

He said: “I think a risk index that looks only at, you know, fire occurrence is missing a big chunk of the problem.

“That needs to, as a country, evolve into thinking about what assets do we want to protect? How do we value those assets? What steps are we willing to take to protect them?”

The fire engineer added: “Other places in the world that would have similar types of vegetation, you would expect similar fire behaviours, but certainly a giant forest in Canada and some of the really huge wildfires that they get in those forests, we’re not going to see that in Scotland.

“I think we’re going to see something different. It’s probably not going to be as intense in absolute terms, but in relative terms it is still going to be significant for the facilities we have.

“I think that’s what we need to able to capture in our models.”

There are ways the worst impacts of wildfires can be halted with crucial components being ensuring the local population is fire-aware, equipping the fire brigade with necessary tools and training and also land management.

Dr Hadden said: “In Scotland, we do a good job with what we've got. I think we're lucky that we're still in kind of the early days of this, the predictions are difficult to make, but the chances are it’s going to get worse.

“It always makes sense to prepare for the worst case.”

However, as humans are the leading cause of wildfires “by miles”, the expert said that he believes that raising public awareness is an aspect in which Scotland may be lagging in.

One of the large causes of additional wildfires during the 2022 heatwaves, was the behaviour often associated with warmer weather in Scotland such as a rise in barbeques and camping.

“That poses another risk to Scotland’s natural environment,” said climate expert Dr Rivington.

“Dry weather encourages people to go camping and having fires, so there is an additional level of risk from behavioural change.”

PART TWO TOMORROW: The recent wildfire which is believed to have become the second largest on record by burnt area and how we can shift the way we see prescribed burning.