Words: Ben Dolphin  

As a ranger in the Cairngorms, I’ve been working to reinstate a riverside walking route damaged by two big floods, in 2014 and 2015. The second was considered a one-in-500-year event, but how long before the path is damaged again?  

In Aberdeenshire, we look over our shoulder to the Muckle Spate of 1829, our most destructive flood on record. But, because humans tend to recall only the very worst, other deluges are forgotten – those of 1642, 1768, 1920 and 1956, to name but a few. Extreme weather is not new. So, viewed against a centuries-long timeline of such events, what exactly is climate change?  

 

Exploring the evidence*  

The UK recording its first day over 40°C in 2022 was a meteorological milestone. That year was the country’s warmest, in records going back to 1884. Second warmest was 2023, and 2024 our fourth warmest. In fact, all of the UK’s ten warmest years are in the 21st century. Tellingly, none of the ten coldest are. We rarely get colder-than-average winters now. Of the last 28 winter months (December/January/February), only five were colder than average.  

Compared with the 1961-90 average, the number of 20°C days has increased by 41% this past decade. What’s more, 25°C days have increased by 63%, 28°C days have doubled and days of 30°C have trebled. Overall, the UK has warmed by 0.25°C per decade since the 1980s.  

And it isn’t just land temperatures that are increasing. UK coastal waters began a warming trend around 1990, which hasn’t abated. In the past decade, only three months recorded mean sea surface temperatures below the 1961-90 average. Three. Out of 120!  

A warming world melts ice on land and at sea, but it also causes thermal expansion of water in the oceans, all of which contributes to rising sea levels. UK sea levels have risen by about 16.5cm since the 1900s; 14cm of that has been since 1993.  

Air holds 7% more moisture for every 1°C increase in global average temperature, so it’s not surprising that recent years have felt wet, too. The 18 months to March 2024 were England’s wettest 18 months in a dataset going back to 1836, and October 2023 saw Scotland’s wettest two-day period in records going back to 1891.  

Rainfall in the UK is highly variable, though. The past decade has been 10% wetter than the 1961-90 average, but winters have been 24% wetter. Aprils have become noticeably drier and, while summers are drier overall, there’s been a significant increase in hourly rainfall rates. Summer rain is increasingly arriving ‘all at once’ via thunderstorms that lead to massive rainfall anomalies, albeit at a local level. There is also greater potential for widespread deluges from ex-tropical storms and ex-hurricanes, due to the higher sea surface temperatures and available energy in the Atlantic.  

Winter storms are still intense and bring more rain, but they aren’t necessarily getting windier. The average annual wind speed in the UK has actually decreased by about 7% since 1970, and there has also been a decrease in the number of days when wind speeds of 40, 50 and 60 knots are recorded.  

That’s not to say there won’t still be extreme storms or violent winds. England’s strongest gust is proof of that – 122mph, recorded on the Isle of Wight in 2022. But certainly in Fife, where I’ve kept a weather station since 2010, the number of days with gale-force (40mph) winds has decreased noticeably in the past decade.  

 

The impact on walking  

Paths have always been impacted by weather. But does climate change mean those impacts are becoming more severe, frequent or long-lasting – and perhaps more costly and inconvenient?  

Walkhighlands (walkhighlands.co.uk), the biggest walking website in Scotland, has received a surge of messages about wind damage and flooding on its routes in the past three years. This is in large part due to Storm Arwen in November 2021 and Storm Babet in October 2023, both of which had disproportionately high impacts due to their unusual storm tracks. Arwen exposed the east of Scotland and North East England to sustained gales from a rare northeasterly direction. Trees that had spent a lifetime bracing themselves against westerly gales had no defence. More than three years later, popular paths in Glen Doll remain closed due to the damage. Babet’s approach from the Bay of Biscay meant the heaviest rainfall came ashore on the east coast rather than the west, onto land that was unaccustomed to such a deluge.  

Flash flooding poses a significant risk to paths. Stronger, faster water flow moves larger objects, exerting considerable erosive force upon the ground. If the terrain is already saturated from previous wet weather, then flooding and tree damage can be just as substantial during lesser storms. Similarly, with rising sea levels, storms needn’t be so severe to hasten coastal erosion. This erosion has always been a ‘thing’ of course, but data from Yorkshire suggests the most recent 10-year average rate is higher than during the past 30 years. The coast is eroding so fast between Hornsea and Bridlington that the route agreed for the new King Charles III England Coast Path already needs to be redrawn.  

The Isle of Wight Ramblers tell me there are currently 18 path closures due to coastal erosion there, and footpath secretary Mike Slater believes the problem is accelerating. Away from the coast, many of the island’s paths are suffering from waterlogging. More rain means existing drainage is overwhelmed, so the paths stay muddy or submerged for longer. For walkers, this could mean the inconvenience of muddy boots or cancelled walks or, more seriously, routes that are suddenly blocked or washed away and remain in disrepair. In an increasingly unpredictable climate, we can expect the lifespan of paths to shorten.  

A warming climate also means paths get overgrown more quickly and for longer. Vegetation wants an average daily temperature of at least 5.5°C to grow, and the past decade (2014-23) had 21% more of these ‘growing days’ than the 1961-90 average.  

When paths aren’t maintained, people veer off. them. This leads to new erosion lines, trampling of sensitive habitats or, in extreme cases, people avoiding the paths altogether. The result is more wear and tear on the remaining good paths in the area. In an increasingly unpredictable climate, we can expect the lifespan of paths to shorten, and our capacity to fix the backlog of damage may be overwhelmed. For walk leaders, pre-walk recces are more important than ever, because you never know what you’ll encounter.  

 

Positive action  

Clearly, there’s much to do to safeguard access in the face of such monumental changes. But there are positive stories to tell. Paths can be adjusted, if necessary, reducing gradients to slow the erosive force of surface water, or installing additional drainage. Infrastructure can be replaced with longer-lasting alternatives, such as the Polydeck footbridge recently funded by Cirencester Ramblers in Preston, Gloucestershire. Manufactured from 850 recycled plastic bottles, this replaced an old wooden bridge over a stream, and should last decades. Path construction and repair are expensive.  

Preventative maintenance is usually more cost-effective than addressing storm damage after the event. On an upland path, one person with a spade, once or twice a year, can be all that’s needed to prevent cross drains and water bars from backing up with silt or stones.  

On the Isle of Wight, Mike commends the rights of way department for laying short sections of aggregate, mixed with concrete, on wet paths. It’s a targeted solution for only the muddiest stretches, though, because – as everywhere – the council is having to make savings. Fix the Fells, the charity that maintains the bulk of Lake District paths, needs £500,000 just to undertake its existing maintenance schedule. Add climate change into the mix, and the same amount of money doesn’t go as far.  

In an era of dwindling public finances, support from volunteers and donors is more important than ever. In 2020, Totnes Ramblers used a legacy donation for new diversion fencing at Tinsey Head, after the cliff fell into the sea. On the Isle of Wight, Ramblers members support their local rights of way team by undertaking minor maintenance. Tasks that can be done quite easily, without an experienced trail leader, are posted online, with the council getting relevant permissions from the landowner.  

When there’s no funding or labour for repairs, other solutions may be needed. Inner London Ramblers is helping its members by compiling a list of mud-free walks (bit.ly/MudFreeLondonWalks). In my last ranger job in West Lothian, we tried ‘resting’ some of our muddier woodland paths when money and resources weren’t available to upgrade them. We made friendly signage, appealing to visitors to help the paths recover from overuse, and signposted drier alternatives. Not everyone heeded the signs, but many did.  

 

The path ahead  

In the most extreme erosion cases, you sometimes have to face the inevitable: the path is lost. For coastal and riverside walking in England and Wales, this is a real problem. Walkers don’t have a right to roam and, because access is specifically tied to paths, when the path is lost, so are the rights of access. But, on the English coast, a solution has been implemented that specifically takes climate change into account. Called ‘roll back’, it legally permits the King Charles III England Coast Path National Trail to retreat inland to maintain its integrity.  

Back in the Cairngorms, we initially considered repairing our riverside path. But since the 2014 and 2015 floods, the riverbank has become more susceptible to erosion. So we’ve reluctantly abandoned the riverside and realigned the path uphill. Future-proofing our path like this doesn’t offer visitors quite the same riverside walking experience, but it’s safe from river erosion and should be okay for decades to come... or until the next unprecedented weather event.  

Ben Dolphin is a ranger, environmentalist and ex-president of Ramblers Scotland:  

*Climate statistics from: State of the UK climate 2023