Category: The Conversation

Source: The Conversation – UK – By Ali Rahman, Assistant Professor of Civil Engineering, University of Leeds

Potholes are a safety risk, source of vehicle damage and recurring annoyance in the UK. They gain special visibility at times of local elections, given that the vast majority of roads are maintained by local authorities. A survey conducted in April found that road condition was the top local issue for voters throughout Britain ahead of the May 7 elections.

The Asphalt Industry Alliance’s (AIA) 2025 report indicates that 17% of the local road network in England and Wales is in poor condition. It estimates that the backlog of repairs would take a staggering 12 years to clear, costing £16.81 billion.

While it’s easy for politicians to point to numbers of potholes filled as a way to gain votes from frustrated drivers, this does nothing to solve the problem in the long run.

Where do potholes come from?

Potholes are not isolated road surface defects, but rather the end-product of a hidden road deterioration process. In typical asphalt roads, bitumen ages, stiffens and becomes brittle over time. Traffic passage causes the road surface to crack.

Once cracks form, water enters the road structure. The weight of vehicles and freeze-thaw cycles over winter cause these cracks to expand and widen, eventually resulting in a pothole. By the time it appears on the road surface, the structural integrity of the subsurface is already compromised.

In the wake of climate change, the UK’s increasingly wet winters accelerate this process, especially on roads that have reached the end of their structural life.

The UK’s approach to repairing potholes is largely reactive: a short-term, localised patch job after the road has failed. Experimental studies show that while this approach is relatively inexpensive per intervention, it suffers from severe underperformance.

These repair jobs often last for just weeks or months in wet or winter conditions before needing to be done again. This “patch and repeat” cycle leads to escalating costs, network disruption and inconsistent road quality.

A much better approach would be preventative maintenance – intervening before failure occurs. Preventative treatments, including surface dressing and crack sealing, yield superior cost-effectiveness because they substantially reduce the frequency of patch failure and replacement.

It’s important to note that filling potholes, in itself, does not add life to roads, apart from temporarily keeping them safe. It is the construction equivalent of throwing good money after bad.

More ambitious would be to establish a predictive and proactive road management system that spans the road’s entire lifecycle. This includes designing and constructing resilient road structures, conducting frequent monitoring, and applying targeted, timely preventive maintenance.

Emerging technology such as advances in data analytics, AI, automation, digital twins and non-destructive testing may make this approach increasingly feasible.

Economics of potholes

Evidence suggests that preventative maintenance would be longer lasting, and significantly more cost-efficient. Spending £1 today on preventative maintenance leads to £4.20 saved within 10 years.

This payback reflects the current poor condition of the local road network in Britain. More sustainable road maintenance would have a rapid effect.

Similar evidence exists for the climate impact. Traditionally, potholes are fixed again and again using cold-mix or hot-mix asphalt – a mixture of stones and petroleum-based bitumen derived from crude oil. This makes the process incredibly carbon-intensive.

Preventative maintenance reduces the long-term carbon costs because roads stay in good condition for longer. As extreme weather such as floods or heatwaves becomes more frequent, the risk of damage to road surfaces increases, making resilience a crucial factor in highway maintenance.

Put another way, preventative road maintenance could be a key part of local authority’s net zero ambitions – whereas the current approach is a liability to this goal.

The electoral focus on fixing potholes therefore seems odd, since the medium- to long-term solution (from a cost, road quality and carbon perspective) is more preventative maintenance.

Why are Britain’s roads so pothole-plagued?

The simple reason that local authorities can’t fix potholes permanently is a lack of funding. However, like many political issues, it is more nuanced.

Our work with the National Highways & Transport Network has found that the public’s satisfaction with roads is substantially driven by the condition of roads within a one-kilometre radius of where they live.

Politically, potholes are obviously visible – they are also classed as safety defects, so there are legal requirements for local authorities to “fix” them in a timely manner. But underlying road condition, while crucial to the emergence of potholes, is more hidden and does not get as much political bandwidth.

Local authorities receive various funding pots for road maintenance, but this funding can sometimes be reallocated to other authority services, such as adult social care. This seriously constrains funding that is spent on road maintenance, although the UK government has recently announced new rules to stop councils from diverting road maintenance funds.

Taken together, this means that preventative maintenance is crowded out by limited funds and the need to repeatedly fix holes that result from a lack of preventative maintenance.

A review of current local road maintenance budget allocations reveals that reactive maintenance consumes 25% of budgets. But the pothole problem is getting worse, which suggests this figure will rise over time.

The relatively recent extra money for road maintenance (£0.5 billion annually) allocated could help, but it won’t go very far unless put into preventative treatments.

Changing to a longer-term solution requires different approaches to government funding and policymaking. But this demands political will at all levels of government, at a time when local authority budgets are already very constrained.

Professor Phill Wheat receives funding from the NHT CQC Network to which he is affiliated as the academic lead.

Ali Rahman does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Why politicians can’t fix potholes permanently – https://theconversation.com/why-politicians-cant-fix-potholes-permanently-281797

Source: The Conversation – UK – By Ben Mayfield, Lecturer in Law, Lancaster University

Directed by Orban Wallace, Our Land explores the countryside access debate in England and Wales through interviews, pastoral shots, lavish illustrations and a walk in the country where the sun always seems to shine.

One percent of landowners own 50% of English and Welsh land. But the right of open access to land by the public, or the “right to roam”, extends to only 8% of this land.

Our Land follows the path of earlier activists such as Marion Shoard and Tom Stevenson who once advanced the access campaign through their experiences and storytelling. Here, the documentary’s star is naturalist and conservationist Nadia Shaikh.

Shaikh explores the teaching power of the English countryside by leading a group of trespassers on a nature walk. She describes her own complex and deep-felt attachment to the countryside as a place of education and personal identity.

Our Land is a title with two meanings – private land ownership for the landowners v the campaign for shared rights in land. The film explores different attitudes to ownership as well as the physical borders between landowners and, in the words of access campaigner and contributor Guy Shrubsole, “the peasants”.

The documentary was filmed during the Darwall v Dartmoor (2023) legal dispute. Landowner Alexander Darwall successfully challenged and outlawed the longstanding right to wild camp on Dartmoor National Park in the High Court. Later overturned by the Court of Appeal and Supreme Court, the High Court ruling in favour of the landowner caused ripples of protest among walkers and campers. They temporarily lost the right to wild camp in Dartmoor – the only place in England where this was allowed by law.

Hedge fund manager Darwall is the most controversial landowner to feature in Our Land, but he is not interviewed in person. Instead, veteran documentary star Francis Fulford (he’s appeared in nine shows, including one about his estate and family) fills the role of aristocratic landowner and pantomime villain.

Fulford provides an insight into the landowner outlook: proud of his family’s place in English and colonial history as well as its roots on the Great Fulford estate. Fulford describes his family as having owned the estate since “time immemorial” and his love of the English countryside is unquestionable.

Indeed, many of the landowners interviewed have a paternal view of the countryside in which they view themselves as temporary guardians. Where opinions differ is how the countryside is best preserved and the extent to which the public should be allowed access to it.

Access and trespass

Trespass itself is a civil matter rather than a criminal offence, which is just as well because the documentary features trespass aplenty.

For instance, campaigning author Nick Hayes crosses the fences of the Drax estate in Dorset to deliver a copy of his Book of Trespass. He discusses the colonial history of the great estates and the role of wider access as a response to the decolonisation movement.

The documentary explains how the English and Welsh culture of access differs from that of close neighbours like Scotland. The Land Reform (Scotland) Act (2003) is celebrated, and contrasted with the exclusionary laws of England and Wales. Shrubsole stands over the border with one foot trespassing in England, the other “lawfully” in Scotland.

The Land Reform Act provides a much wider right to roam the Scottish countryside than the Countryside and Rights of Way Act in England (2000). It has a presumption in favour of public access and only minor exclusions such as private gardens and some industrial land. By contrast, the English “right to roam” supplements our existing network of footpaths, but extends only to mountain, moor, heath, down and common land. Great swathes of land are left inaccessible to the public.

The law is a central character in the access debate but exists only in the background of this documentary. We learn about the Norman conquest and enclosure of the commons in the 12th to 19th century. It was a process of consolidating, privatising and fencing off shared agricultural land (common land) in Britain, transforming it into individually owned, fenced fields. This change abolished traditional communal rights for grazing and farming.

However, there is less about the mixed success of earlier attempts to open countryside such as the Access to Mountains Act (1939), post-war National Parks Act (1949) or the Countryside and Rights of Way Act. English legislative failures might be able to teach us as much as Scotland’s successes.

Disagreement and concession

As the documentary draws to its conclusions there are some limitations to the format of landowners and campaigners being interviewed separately. We hear from both sides of the access debate but there are few opportunities to see the two sides in conversation.

Fulford is goaded from behind the camera on his views about sharing his land with visitors, but no representatives from either side have the opportunity to join one another in debate.

This leaves some assertions unchallenged, such as those of the affable Hugh Inge-Innes-Lillingston, owner of the Thorpe estate in Staffordshire. On the topic of rewilding, he contends that land cannot be truly rewilded if public access is allowed. But this reductive position ignores the nuanced ways that visitors and wilderness can coexist.

Throughout, many of the featured landowners and access campaigners agree on the artificial nature of landownership, their individual powerlessness to effect change and on the social and legal constructs that trap us all in an uncomfortable standoff.

As the documentary closes with trespassers talking and singing around a fire, I was left wishing that the cast of landowners could have joined them in their conversation.

The climate crisis has a communications problem. How do we tell stories that move people – not just to fear the future, but to imagine and build a better one? This article is part of Climate Storytelling, a series exploring how arts and science can join forces to spark understanding, hope and action.

Ben Mayfield does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Our Land: who owns the countryside? New documentary explores the access divide in England and Wales – https://theconversation.com/our-land-who-owns-the-countryside-new-documentary-explores-the-access-divide-in-england-and-wales-282001

Source: The Conversation – UK – By Edward Forman, PhD Candidate, Climate Tipping Points, University of Southampton

Imagine being tasked with counting every blade of grass in a field, noting every single species as you go. This is not far from the challenge many scientists face when analysing microscopic samples packed with thousands of tiny particles.

Imaging flow cytometry (IFC) solves this by guiding particles single-file past a camera and lasers, capturing detailed images of tens of thousands per second. It records the particles’ size, shape and optical properties, turning what was once painstaking manual work into automated analysis.

IFC has become a staple of biomedical research, with scientists using it to study blood viruses or classify tumour cells. It’s also increasingly used in environmental science – for example, to monitor water quality and detect microplastics.

Now, we’re using this medical tech on ancient mud, peat and lake sediments. It may help us identify exactly when ancient climate tipping points were crossed.

Blood to mud

To predict future climate change, we need to understand how things changed in the past. To do this, scientists use natural archives such as sediment found at the bottom of lakes or oceans, long “cores” drilled into peat or ice, or stalagmites and stalactites found in caves.

These archives effectively work as layered climate logbooks, recording environmental change over hundreds to thousands of years. As researchers dig deeper into sediment, peat or ice, they move further back in time. Each layer captures conditions at the time it was formed, from temperature and precipitation to the strength of ocean currents and wind belts.

Microscopic fossils and climate change

The abundance of certain microscopic fossils can be used to reconstruct these past conditions. For instance, the presence of certain species of pollen in peat or algae in lake sediments reflects changes in the climate system.

Pollen preserved in Amazon rainforest mud today is very different from that in Arctic tundra. In the far future, geologists will be able to tell from the fossilised form of this pollen which region once had tropical trees, and which had cold-weather shrubs.

This approach to reconstruction underpins a large portion of palaeoclimate research. Traditionally, however, it has involved counting thousands of particles by eye under a microscope. Because this is so time-consuming, only a small fraction of the total sample is analysed, while the rest is estimated by scaling up those results.

IFC dramatically speeds up counting, meaning climate reconstructions that previously took months can now be done much faster.

This makes it possible to produce higher-resolution records by analysing more samples, and to quantify rare species. Scientists using this technology can focus on questions that were previously too time-consuming to address, such as exactly when a certain environmental change occurred in the deep past.

Also, IFC digitises each sample, making results easier to share, reproduce and reanalyse, promoting more robust, open science.

Hidden patterns and tipping points

As IFC makes it feasible to count a much larger fraction of any given sample, it allows us to detect subtle changes that would have taken too long to detect manually.

Uncovering these small shifts in the particles found in a given place could provide early warning signals of abrupt climate change. For example, we can trace the migration of wind belts via the abundance of non-native pollen species at particular locations. Such movement of the winds may be responsible for triggering sudden change, perhaps by melting ice sheets or drying out a rainforest.

As a result, we may be able to precisely date the timing of past climate tipping points – and with that, the order in which these thresholds were crossed. This could let us distinguish between cause and consequence, as we can determine which changes happened first.

This approach also has the potential to uncover entirely new data, such as the presence of rare species at particular sites. These new records can then act as novel proxies for climate change – leading to more detailed reconstructions and deeper insights into how the climate works.

A tool designed to scan blood now offers us an exciting opportunity to read Earth’s history in finer detail and decipher hidden mechanisms. It could also help us predict abrupt changes in the near future.

Edward Forman is affiliated with Climate:Change.

Zoë Thomas receives funding from a UKRI Future Leaders Fellowship.

– ref. How a repurposed medical device is helping us investigate ancient climate tipping points – https://theconversation.com/how-a-repurposed-medical-device-is-helping-us-investigate-ancient-climate-tipping-points-281417

Source: The Conversation – UK – By Katryna Niva, Cassar Lab, Duke University

We replaced the stove with plywood, turning the kitchen of the dive boat into an impromptu research lab. Plugging in wires and connecting tubing, we assembled a scientific instrument within the cramped cabin.

Then we cast off into Halifax Harbour, Canada, surveying the turquoise waters for signs of an unusual test: could we use the ocean itself to remove carbon dioxide from the air?

Carbon dioxide (CO₂) is the most important driver of climate change, but it cannot be seen. Its build-up in the atmosphere is gradual. Its worst consequences take time to emerge. Even if emissions fell sharply tomorrow, the CO₂ already released would continue to warm the planet.

That is why scientists and policymakers are increasingly turning to carbon dioxide removal (CDR): taking CO₂ that has already been released back out of the air. So far, most large-scale CDR has focused on land, such as reforestation. But land is finite, competes with food production and biodiversity, and stored carbon can be lost through fire or deforestation. As emissions continue to outpace what these approaches alone can manage, attention has turned toward the ocean.

The overlooked role of the ocean in carbon storage

The ocean covers about 70% of the Earth’s surface and holds roughly 50 times the amount of carbon found in the atmosphere. Before the industrial revolution, carbon moved between air and sea in near balance. As industrial activity increased atmospheric CO₂, more of it dissolved into seawater and the ocean became more acidic.

All that dissolved carbon has resulted in the ocean storing about a third of human CO₂ emissions since the industrial revolution — substantially slowing the pace of climate change. The emerging question is whether we can build on this natural service. The field exploring that possibility is known as marine carbon dioxide removal (mCDR).

All mCDR approaches aim to reduce the amount of dissolved CO₂ at the ocean surface, converting it into more stable forms. When surface CO₂ is reduced, more CO₂ from the atmosphere dissolves into the sea.

Reducing surface CO₂ – so the sea absorbs more

One approach involves adding alkaline minerals – often crushed or processed rocks like limestone or basalt – to seawater. This reduces acidity and increases the capacity of seawater to absorb more carbon and store it for centuries to come. This is the strategy under development by Planetary Technologies in Halifax Harbour, Canada. There, alkaline minerals have been introduced to seawater through the cooling water discharge pipe of a natural gas burning power plant.

Another approach relies on biology. The ocean is filled with microscopic organisms that photosynthesise, using dissolved CO₂ to grow and reproduce. Some of this carbon sinks into deeper waters, through a process known as the “biological carbon pump”. By adding the nutrients that these organisms need to thrive, this effort hopes to increase microorganism populations and, ultimately, strengthening the biological carbon pump.

How do we know it works?

Whether chemical or biological, these approaches face the same questions: how much additional CO₂ is actually being removed from the atmosphere? And what are the ecological consequences?

The processes involved are invisible to the naked eye. The organisms are microscopic. The carbon transformations are chemical. Yet if marine carbon removal is to scale to climate-relevant levels, it will require rigorous measurement, transparency and public trust.

In the Cassar Lab at Duke University, we develop instruments to detect subtle changes in seawater chemistry. They continuously measure dissolved gases and other tracers, allowing us to reconstruct what microorganisms are doing and how carbon is moving through the system.

In August 2025, we deployed one of these tools in the turbulent waters surrounding one of the world’s first coastal ocean alkalinity enhancement projects, off Nova Scotia, Canada. This instrument was a mass spectrometer that extracts and quantifies dissolved gases from seawater. These readings give us insight into the ecosystem’s balance between photosynthesis and respiration – and therein, an understanding of how stressed or healthy the surrounding ecosystem is. Working alongside researchers tracking the chemical changes of the mCDR work underway, we focused on understanding how marine microorganisms were responding.

Another instrument, known as the Gopticas, allows a precise quantification of how much photosynthesis is happening in a seawater sample. The Gopticas was recently exhibited Prototypes for Humanity, an international innovation initiative based in Dubai, highlighting how tools developed for fundamental oceanography can also underpin climate accountability. This allows stronger quantification of ecosystem health as well as carbon influx.

A scalable approach to mCDR monitoring

We are now forming a team that can deploy these tools to directly quantify the amount of CO₂ being converted into longer-lived forms – and to spot early signs of ecological disruption.

This kind of monitoring is crucial. It allows us to distinguish between carbon that is briefly cycled near the surface and carbon converted into forms likely to remain stored for centuries. It also provides early warning if an intervention begins to disrupt marine biology. The work in Halifax marked the first application of our instruments to mCDR initiatives, but we look forward to applying these same approaches across regions and mCDR approaches.

Developing robust methods to quantify both carbon removal and ecological impact before large-scale deployment is essential. Without credible verification, claims of carbon removal risk outpacing evidence. And without clear evidence of environmental safety, public support will falter.

If marine carbon dioxide removal is to make a meaningful contribution to climate mitigation, it must rest on precise measurement and accountability. Governments, regulators and investors will need confidence that reported carbon removal is real and durable – and that marine ecosystems are protected.

Standing on the deck of the dive boat, staring out at the plume of alkaline waters emerging from the pipe, it’s easy to be struck by a feeling of awe. This experiment is tiny compared to global climate change – a drop in the ocean. But it offers a glimpse into a more optimistic future.

This article was commissioned in conjunction with Prototypes for Humanity, a global initiative that showcases and accelerates academic innovation to solve social and environmental challenges. The Conversation was a media partner of Prototypes for Humanity 2025.

Katryna Niva works for Duke University. Her research is also supported in part by the Carbon to Sea Initiative.

This article was commissioned in conjunction with Prototypes for Humanity, a global initiative that showcases and accelerates academic innovation to solve social and environmental challenges. The Conversation was a media partner of Prototypes for Humanity 2025

Alireza Merikhi does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. The ocean is fighting climate change and we’re trying to help it – here’s how – https://theconversation.com/the-ocean-is-fighting-climate-change-and-were-trying-to-help-it-heres-how-271554

Source: The Conversation – UK – By Stephen Coleman, Professor of Political Communication, University of Leeds

Every election is a storytelling contest, with campaigning parties competing to frame the plot. This year’s local elections, the largest test of voters’ mood since the 2024 general election, have been dominated by two master-narratives.

The first is about the demise of the old two-party system under which Labour and Conservatives have been the battling giants for almost 100 years. Vast regions of England have long been regarded as safe electoral zones. They have been disrupted only occasionally by strategic incursions by the Liberal Democrats or mid-term revolts against whoever formed the Westminster government.

The story of the 2026 local elections is one of a conspicuous public impulse to punish the old incumbents, resulting in the ascendancy of the new kids on the political block – Reform UK and the Greens.

In the 2024 general election, Reform won 15.3% of the vote in English constituencies and the Green Party won 7.3%. Since then, Labour’s poll ratings have fallen and the Tories have hardly recovered from their devastating result when they lost 238 seats.

But the story amounts to more than numbers. We are witnessing a pervasive and powerful expression of desire by the electorate – not just for radical political alternatives, but for a radical alternative to politics itself.

The rise of the outsider

This is a story about the rejection of anyone who looks or speaks like a conventional politician. Both Reform leader Nigel Farage and Zack Polanski, the leader of the Greens in England and Wales, have cultivated images of themselves as outsiders who eschew the caution and attachment to well-rehearsed cliche that has so discredited their opponents.

It was an election in which voters came to believe that what these political mavericks say is what they actually mean. Left-inclined voters might feel repelled by Farage’s strident nationalism and right-inclined voters might regard Polanski as a dangerous dreamer. But neither doubts that they are up against genuine commitments.

Meanwhile, Labour and Conservative candidates have continued to campaign in the way they have been for decades. This means they have often actually been talking about local policies relating to refuse collection, libraries and care services. The newcomers have tended to ignore the rules of the game and fought their campaigns on headline values rather than policy detail.

Reform UK has said that it planned to open migrant detention centres in areas where the vote for the Green Party is high, while Green candidates in Haringey produced an election video stating that if elected they would uphold the inalienable rights of the Palestinian people.

The fact that elected local councillors lack any power to place detention centres in other areas or determine UK foreign policy was ignored. Local elections were turned into a showcase for a style of politics in which cultural symbolism outweighed the prudential technicalities of local governance.

Read more:
After a year of Reform UK in local government, the cracks are starting to show

However, as Reform politicians are learning in the few areas where they already hold local power, attention to policy complexity calls for rather more than the repetition of populist slogans, leading several of their councillors to leave the party as the responsibility of hard policy choices has dawned upon them.

For many voters, these local elections present a chance to gamble on the promise of the untried. And this brings us to the second story of this campaign, which is taking place almost exactly a decade after the Brexit referendum.

That was a moment when the politics of “anything must be better than this” appealed to electoral gamblers. As an insurgency of the unheard, Brexit reflected a feeling that the political establishment needed a good poke in the eye. This was regardless of the consequences for the assailants.

A key story of this year’s local elections is that the division between Leavers and Remainers, far from fading into the distance, has hardened over the past decade. Socially liberal Remainers and culturally conservative Leavers have each sought political homes in which to complete what they see as unfinished business.

YouGov polling in early 2026 suggested that how people voted on Brexit is a key predictor of how they would vote in this year’s elections. Some 50% of those who voted Leave in 2016 intended to back Reform this year. Among Remainers, the largest number (28%) say that they will vote Labour, but both the Greens and the Liberal Democrats each have around a fifth of the Remainer vote, making them the largest political home for those who opposed Brexit ten years ago.

The results of these elections say a lot about how much voters are tired of the old incumbents and continue to dwell on changes that Brexit promised or threatened. In terms of how councils will be run between now and the next local elections, during a period of constrained public spending, hollowing out of services and energy insecurity, this election campaign has had precious little to say.

Stephen Coleman does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. English local elections 2026: a story of a new kind of politics – https://theconversation.com/english-local-elections-2026-a-story-of-a-new-kind-of-politics-282409