environment – Page 3 – Cabot Institute for the Environment blog

Nearly a quarter of people in the UK flush wet wipes down the toilet – here’s why they shouldn’t

Posted on April 19, 2023 by amanda.woodman-hardy

Charlotte Lloyd, University of Bristol

Whether you’re cleaning your house, your car or your child, there are a variety of wet wipes manufactured for the job. Wet wipes are small, lightweight and extremely convenient. They have become a staple in most of our lives, particularly so during and since the COVID-19 pandemic.

But according to Water UK, an organisation representing the water industry, flushing wet wipes down the toilet is responsible for 93% of sewer blockages and costs around £100 million each year to sort out. And the majority of these wipes, about 90%, contain plastic.

Water UK also found that 22% of people admit to flushing wipes down the toilet, even though most of them knew they posed a hazard. And it’s estimated that 300,000 sewer blockages occur every year because of “fatbergs”, with wet wipes one of the main causes.

But it seems wet wipes could soon be banned in England – well, at least the ones that contain plastic – as the government has said it will launch a public consultation on wet wipes in response to mounting concerns about water pollution and blockages. This follows pledges made by major retailers, including Boots and Tesco, to discontinue the sale of such products.

Market projections show that 1.63 million tons of material will be produced in 2023 for wet wipes globally – an industry worth approximately $2.84 billion (£2.04 billion). Though these figures are likely to be on the conservative side as manufacturers increased the production of disinfecting wipes in 2020 during the pandemic – and have remained at the same level since.

Despite the popularity and wide use of wet wipes, not a lot is known about their environmental footprint. This is because manufacturers are not obliged to state what the wipes are made from on the packaging, only the intentionally added ingredients. This creates a challenge for both scientists and consumers alike.

What we know

Wet wipes are made from non-woven fibres that are fused together either mechanically or with the aid of chemicals or heat. The individual fibres can be made from either natural (regenerated cellulose or wood pulp) or petroleum-based (plastic) materials, including polyester and polypropylene.

Most wet wipes are a mixture of natural and synthetic fibres – and the majority contain plastic. As well as the fibres, wet wipes also contain chemicals, including cleaning or disinfecting agents which are impregnated into the material.

Wet wipes, disinfecting wipes. — Wet wipes can cause a lot of issues for our sewerage system.
JoyImage/Shutterstock

Some wipes are designed to be “flushable” and contain chemical binding agents that are designed to release the fibres of the wipe when they are exposed to water. This means that if wipes are not disposed of correctly, they can create both a plastic and a chemical hazard to the environment.

It’s well known that plastic breaks down extremely slowly and persists for centuries in landfill. And if plastic-containing wipes are released into the environment – either through littering or via the sewerage system – they can pose a number of hazards.

The plastic problem

When wet wipes reach the environment – including soil, rivers and the ocean – they generate microplastic pollution in the form of microfibers. Microfibers are one of the most prevalent types of plastic pollution in the aquatic environment and affect ecosystems as well as potentially human health through their introduction into the food chain.

The problem has been exacerbated by these “flushable” wipes. One study identified seven different types of plastics as potential components of flushable wipes – meaning that they still risk being a source of microplastic pollution. Recent work has confirmed that wet wipes (along with sanitary products) are an underestimated source of white microfibers found in the marine environment.

Data on the environmental impact of the associated chemicals is lacking, but this is something my research group is currently working on. What is known though is that plastics have the ability to absorb other contaminants such as metals and pesticides as well as pathogens. And this provides a way for pollution to be transported large distances through the environment.

Flushable wipe going down the toilet. — Are flushable wipes really flushable?
Shutterstock/nito

Driven by environmental concerns as well as impending legislation, many plastic-free wipe products are now available or being developed. But even products made from natural fibres can still pose a problem to sewerage systems and so safe disposal – in a bin – is key.

The scientific evidence surrounding the environmental effects of bio-based plastics (plastics made from non-petroleum sources such as corn or potato starch) is also lacking, so caution is needed when thinking about simply switching from petroleum-based to bio-based plastics.

With this in mind, reusable washable products are a great alternative to disposables and have a much smaller environmental footprint. They are particularly handy around the home when washing is convenient.

That said, there will remain a market for disposables, but manufacturers should have to clearly label what the wipes are made from so that consumers can make a more informed choice.

This blog is written by Cabot Institute for the Environment member Dr Charlotte Lloyd, Royal Society Dorothy Hodgkin Research Fellow and Lecturer in Environmental Chemistry, University of Bristol.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

What it means to be of the mountains: ethnography of social embrace in Nivica, Albania

Posted on March 31, 2023 by amanda.woodman-hardy

Aisling Tierney (right) with local Albanians during her research trip. — Aisling Tierney (right) with local Kurvalesh during her research trip to Albania.

In 2022, I made my fifth visit to the village of Nivica in the heart of the Kurvelesh mountainscape. It was a quick trip for lunch and to say hello to the community that has made me welcome there since 2017. Upon visiting the house of the first couple who hosted me, I was greeted with hot tea, sharp raki and sweet cakes. The older couple, Bame and Trendefille, cannot stop themselves from treating me like family. They embrace me. They take my hand to lead me to the indoor seating area. They hug me constantly.

Just a week before the visit I lost my father after a long and terrible illness. There was something profound about feeling so loved in a familiar domestic setting. I was different now. How I received their outpourings of love felt more meaningful than ever. When they asked about my father they were heartbroken to hear of his death. Both my parents were invited innumerable times by the couple, but there was never a chance my mother would make the trip up the wild rocky roads!

During the visit they shared stories of time together with my travel companions. My ego was certainly entertained by their generosity of spirit in these retellings. Amongst their chats, the man of the house said something so lovely and unexpected that I was left speechless. He said that I am Kurveleshi – that is, I am of the Kurvelesh, I am one of them. Coming from one of the most respected members of the community, it meant the world to me.

To be of the Kurvelesh means a lot of things and will be different depending on who you ask. What seemed to be important to Bame was that I showed respect. Concepts like Besa and Kanun are important in the region. The former is all about keeping promises and acting honourably, like a pledge to do right by people. The latter is an overarching customary law governing all aspects of traditional life, passed on through oral tradition for centuries. The Kurvelesh is the last remaining area where Kanun survives beyond the Ottoman era and into the modern age.

Bame compared my team of archaeological researchers to other foreign groups from a range of disciplines. He said we were different, we embraced the mountains and the local culture. We took a different mindset into our research practice that included the community in both personal and professional terms. It is not an exaggeration to say that the team feels like Kurvelesh is a second home. It is no longer a remote foreign place full of the unknown. For us, it is now a place of familiar and familial faces and friendships.

We love the people of the mountains and they love us back.

One of the most unexpected comments I received was why my team laughs so much! We are a jovial bunch, always singing and joking around. It seems less easy to laugh in the Kurvelesh. Life has been hard in the wake of Communism, which is still a sensitive subject for most of the older community. People do not like to talk about their experiences in forced labour groups and the suppression of cultural traditions. We do not push the subject. Like much of Albania, this is also a site of several war fronts, not least of which saw the razing of the whole village by the Greeks in 1913. Remnants of these warfronts constitute a large body of our collection of artefacts from fieldwalking surveys. These objects tell stories themselves. The bullet casings from one misfiring gun are found in several locations adjacent to the modern village. Decorative uniform badges are found in local fields. Artillery shells and rusted guns are even collected and hung on display in homes and the single village café. The past is visible, even if it is unspoken.

We also received comments about how the team is managed. Curious locals asked me how I get my team to work without shouting at them. They were surprised that we were all volunteering our time unpaid and at our expense to investigate local heritage. The fact that we were not renumerated seemed to change their perspective on our intentions in a positive manner.

The community were outwardly pleased that we were fully open about our research. They talked about their assumptions about foreign groups and how the archaeology of the country has been pillaged by others. Our efforts included welcoming anyone to visit the site at their leisure. We were frequently visited by the young and old alike, sometimes as a detour from a walk or while passing with a herd of goats to laugh at us working in the rain. We made our work even more visible by taking finds for cataloguing to tables in the local café, so that the whole community could see everything we had and how we worked with it. Informal lessons and visualisations helped the community to understand the breadth of our work. They were delighted to learn of our multi-period approach and began to bring objects for us to record.

Over time, the community began to trust us. Through friendships and openness, they could see we were there for the right reasons. One local man showed up one day with a purple plastic bag filled with pottery sherds and bronze coins. He allowed us to photograph and record them onto our database. Every item was handed back to him the next day in perfect condition. This happened a few times. Each instance proved we meant what we said – we were not there to take anything, we were there to observe, learn and record only. At the end of each season, we handed all the finds to the local leadership for storage, with some pottery samples collected by the national Institute of Archaeology for their archives.

The community were also surprised that we value their knowledge and insights. We were positively enthused when offered tours of sites that might interest our archaeological endeavors. Every suggestion and prompt from the community was cherished and integrated into our research, valued as of equal value to anything considered more “academic”. This respect for local knowledge also helped our reputation.

The reports compiled after each season were hugely beneficial in communicating the value of the compiled data. They included drawings and maps that showed the community how the data comes together to tell their stories. They were also keen to see how we used LiDAR and drone imaging with our GPS records to map concentrations of finds across the landscape. The visual stories transcended linguistic barriers and helped everyone see why our work was useful and relevant to them. For example, local B&B owners typically spend the most time with visitors and our data is helpful in conveying the history of the landscape to those eager to learn, whether domestic or foreign. The community hopes that the information plaques that we have contributed to and walking trails supported by other international groups, created in recent years, will help foster better understanding of their local history. In the future, they will create a museum featuring artefacts collected by us and the community alike.

Goats being herded in Albania along a winding mountain road.

What makes our research fieldwork a bit different than most is that we take with us interdisciplinary perspectives. The Sustainable Development Goals (SDGs) are the lens by which we evaluate our work and contributions. This maps well onto local and national initiatives that seek to offset long-standing issues facing mountain communities. These issues include depopulation, losing traditional intangible cultural heritage, lack of attractive jobs, and environmental sustainability. Our heritage story is a small part of a much bigger picture. Rather than consider our work on our terms, we embrace domestic value systems and methods of seeing value.

One of our team has undertaken a project interviewing the community about their lives and experiences culminating in an MLitt dissertation, How do rural communities negotiate the legacy of a contested landscape in contemporary southern Albania? (A. Donnelly 2020, 95pps). Her work explores the landscape, agricultural practices, ethnobotanical knowledge, local recipes, conflict and rebellion, unique worship practices, folklore, and music. A taught masters student also produced a dissertation, How can social media function as a tool for initial tourist development? Lessons from rural Albania (R. Sanders 2020, 77pps). Her research reviewed the multivocality of tourists, the power of word-of-mouth marketing, and authenticity of touristic experience as demarcated by local business owners. Other outputs include fieldwork reports in 2018 (Tierney et al. 131pps) and 2019 (Tierney et al. 41pps), and multimedia engagement through public-engagement videos and at conferences. Additionally, I have integrated learnings from fieldwork into both undergraduate and postgraduate teaching at two universities. Several peer reviewed papers are underway and will be published soon. They include a comprehensive overview of the SDGs at Nivica, fieldwork survey analysis and artefact analysis.

In academia, quantifiable outputs and impacts are championed. Even in the realm of public engagement academic discourse, the value of authentic, deep and personal trusting relationships are muted. For me, hearts and minds in a framework of respect are worth more than anything else. If our research work enables us to contribute positively to a community that we adore, then our work is a success. I am optimistic that this personal narrative helps to contribute something to how we view ourselves as fieldwork researchers in relation to the places and communities that we encounter and, hopefully, embrace. In a world replete with mental health strain and professional angst, as the higher education system pinches more and more, there are things more valuable than traditional academic milestones. It is one thing to love one’s work, it is another to be truly loved back by the people we work for.

———————————

This blog is written by Cabot Institute for the Environment member, Dr Aisling Tierney.

Intense downpours in the UK will increase due to climate change – new study

Posted on March 8, 2023March 8, 2023 by amanda.woodman-hardy

A flash flood in London in October 2019.
D MacDonald/Shutterstock

Elizabeth Kendon, University of Bristol

In July 2021, Kew in London experienced a month’s rain in just three hours. Across the city, tube lines were suspended and stations closed as London experienced its wettest day in decades and flash floods broke out. Just under two weeks later, it happened again: intense downpours led to widespread disruption, including the flooding of two London hospitals.

Colleagues and I have created a new set of 100-year climate projections to more accurately assess the likelihood of heavy rain downpours like these over the coming years and decades. The short answer is climate change means these extreme downpours will happen more often in the UK – and be even more intense.

To generate these projections, we used the Met Office operational weather forecast model, but run on long climate timescales. This provided very detailed climate projections – for every 2.2km grid box over the UK, for every hour, for 100 years from 1981 to 2080. These are much more detailed than traditional climate projections and needed to be run as a series of 20-year simulations that were then stitched together. Even on the Met Office supercomputer, these still took about six months to run.

We ran 12 such 100-year projections. We are not interested in the weather on a given day but rather how the occurrence of local weather extremes varies year by year. By starting the model runs in the past, it is also possible to verify the output against observations to assess the model’s performance.

At this level of detail – the “k-scale” – it is possible to more accurately assess how the most extreme downpours will change. This is because k-scale simulations better represent the small-scale atmospheric processes, such as convection, that can lead to destructive flash flooding.

The fire service attending to a vehicle stuck in floodwater. — Flash flooding can be destructive.
Ceri Breeze/Shutterstock

More emissions, more rain

Our results are now published in Nature Communications. We found that under a high emissions scenario downpours in the UK exceeding 20mm per hour could be four times as frequent by the year 2080 compared with the 1980s. This level of rainfall can potentially produce serious damage through flash flooding, with thresholds like 20mm/hr used by planners to estimate the risk of flooding when water overwhelms the usual drainage channels. Previous less detailed climate models project a much lower increase of around two and a half times over the same period.

We note that these changes are assuming that greenhouse gas emissions continue to rise at current rates. This is therefore a plausible but upper estimate. If global carbon emissions follow a lower emissions scenario, extreme rain will still increase in the UK – though at a slower rate. However, the changes are not inevitable, and if we emit less carbon in the coming decades, extreme downpours will be less frequent.

The increases are significantly greater in certain regions. For example, extreme rainfall in north-west Scotland could be almost ten times more common, while it’s closer to three times more frequent in the south of the UK. The greater future increases in the number of extreme rainfall events in the higher resolution model compared with more traditional lower resolution climate models shows the importance of having k-scale projections to enable society to adapt to climate change.

As the atmosphere warms, it can hold more moisture, at a rate of 7% more moisture for every degree of warming. On a simple level, this explains why in many regions of the world projections show an increase in precipitation as a consequence of human-induced climate change. This new study has shown that, in the UK, the intensity of downpours could increase by about 5% in the south and up to about 15% in the north for every degree of regional warming.

Group of girls with an umbrella walking through a city. — The projected increase in the intensity of rainfall is significantly greater in certain regions.
NotarYES/Shutterstock

However, it is far from a simple picture of more extreme events, decade by decade, as a steadily increasing trend. Instead, we expect periods of rapid change – with records being broken, some by a considerable margin – and periods when there is a pause, with no new records set.

This is simply a reflection of the complex interplay between natural variability and the underlying climate change signal. An analogy for this is waves coming up a beach on an incoming tide. The tide is the long-term rising trend, but there are periods when there are larger waves, followed by lulls.

Despite the underlying trend, the time between record-breaking events at the local scale can be surprisingly long – even several decades.

Our research marks the first time that such a high-resolution data set has spanned over a century. As well as being a valuable asset for planners and policymakers to prepare for the future, it can also be used by climate attribution scientists to examine current extreme rainfall events to see how much more likely they will have been because of human greenhouse gas emissions. The research highlights the importance of meeting carbon emissions targets and also planning for increasingly prevalent extreme rainfall events, which to varying degrees of intensity, look highly likely in all greenhouse gas emissions scenarios.

The tendency for extreme years to cluster poses challenges for communities trying to adapt to intense downpours and risks infrastructure being unprepared, since climate information based on several decades of past observations may not be representative of the following decades.

This blog is written by Cabot Institute for the Environment member Elizabeth Kendon, Professor of Climate Science, University of Bristol. This article is republished from The Conversation under a Creative Commons license. Read the original article.

Seasonal Worker visa route encounters problems

Posted on February 27, 2023March 3, 2023 by amanda.woodman-hardy

Radio 4 interview with Dr Lydia Medland

Following the Home Office revocation of the license of one of the seasonal agricultural worker recruitment operators, Dr Lydia Medland spoke to BBC farming today on 20th February 2023 about the scheme (listen here).

The UK Seasonal Worker visa route allows workers to come from around the world to work for up to six months. There are (or were) seven ‘operators’ of the scheme. These are licenced by the government as the recruiters and sponsors of the workers and are responsible for both enforcement of the scheme requirements, particularly ensuring that workers go home at the end of their stay, and for worker protection.

The UK has had some form of seasonal worker migration scheme since the end of World War II, but the current scheme dates from 2019, when following Brexit, EU workers no longer had access to the UK labour market, and UK fruit and vegetable growers and food producers had to look elsewhere to fill seasonal labour vacancies.

At the end of 2021, Dr Medland and Dr Scott (University of Gloucestershire) wrote a briefing outlining problems in the design of the scheme recommending major changes including a guaranteed minimum income, and for workers to have full access to public services.

In her interview with Radio 4 on 20th February Dr Medland spoke of her concerns that the same companies are responsible for ensuring workers’ return as are responsible for preventing their exploitation, saying that with ‘…outsourcing to for-profit businesses of this dual very important role, it isn’t surprising that something has gone wrong, I think the UK should go back to the drawing board on this scheme.’ Academic research has found (see for example Costello and Freedland, 2014) that where there is an interaction between protection of workers and enforcement of migration law, the enforcement role takes precedence. This leaves workers vulnerable to exploitation because they fear the same organisations and laws that are also meant to protect them.

Radio 4 put these comments to the Home Office who said, ‘The seasonal workers route has been running for three years and each year there have been improvements.’ However, the increasing scrutiny of the scheme by researchers, NGOs and journalists may be having some impact because on 23rd February 2023 Mark Spencer, the Farming Minister announced that Seasonal Workers coming to the UK on the scheme would be guaranteed 32 hours a week of work. This is in response to reports that workers are returning in debt because of there is less work than originally expected.

Whilst the Seasonal Workers visa route is no longer officially a ‘pilot’ it has only been renewed until the end of 2024 and it remains open to significant review. This policy is part of the focus of the ‘Working for 5 a day’ project because seasonal migrant workers are a vital part of the labour force that ensures consumers have access to fruit and vegetables. We will continue to follow this policy development and its changing context.

——————————-

This blog was written by and has been reposted with kind permission from Cabot Institute for the Environment member Dr Lydia Medland. View the original blog.

Climate change is threatening Madagascar’s famous forests – our study shows how serious it is

Posted on January 20, 2023March 27, 2023 by amanda.woodman-hardy

Urgent action is needed to protect Madagascar’s forests.
Rijasolo/AFP via Getty Images

Global climate change doesn’t only cause the melting of polar ice caps, rising sea levels and extreme weather events. It also has a direct effect on many tropical habitats and the animals and plants that inhabit them. As fossil fuel emissions continue to drive climate change, large areas of land are forecast to become much hotter and drier by the end of this century.

Many ecosystems, including tropical forests, wetlands, swamps and mangroves, will be unable to cope with these extreme climatic conditions. It is highly likely that the extent and condition of these ecosystems will decline. They will become more like deserts and savanna.

The island nation of Madagascar is of particular concern when it comes to climate change. Of Madagascar’s animal species, 85% cannot be found elsewhere on Earth. Of its plant species, 82% are unique to the island. Although a global biodiversity hotspot, Madagascar has experienced the highest rates of deforestation anywhere in the world. Over 80% of its original forest cover has already been cleared by humans.

This has resulted in large population declines in many species. For example, many species of lemurs (Madagascar’s flagship group of animals) have undergone rapid population decline, and over 95% of lemur species are now classified as threatened on the International Union for Conservation of Nature (IUCN) Red List.

Drier conditions brought about by climate change have already resulted in widespread bush fires throughout Madagascar. Drought and famine are increasingly severe for the people living in the far south and south-western regions of the island.

Madagascar’s future will likely depend profoundly on how swiftly and comprehensively humans deal with the current climate crisis.

What we found

Our study investigated how future climate change is likely to affect four of Madagascar’s key forest habitat types. These four forest types are the dry deciduous forests of the west, humid evergreen forests of the east, spiny bush forests of the arid south, and transitional forests of the north-west corner of the island.

Using computer-based modelling, we simulated how each forest type would respond to climate change from the current period up to the year 2080. The model used the known distribution of each forest type, and current and future climatic data.

We did this under two different conditions: a mitigation scenario, assuming human reliance on greenhouse gas reduces according to climate commitments already made; and an unmitigated scenario, assuming greenhouse gas emissions continue to increase at their current rate.

Our results suggest that unmitigated climate change will result in declines of Madagascar’s forests. The area of land covered by humid forest, the most extensive of the four forest types, is predicted to decrease by about 5.66%. Dry forest and spiny bush are also predicted to decline in response to unmitigated climate change. Transitional forest may actually increase by as much as 5.24%, but this gain will almost certainly come at the expense of other forest types.

We expected our model to show that mitigating climate change would result in net forest gain. Surprisingly, our results suggest entirely the opposite. Forest occurrence will decrease by up to 5.84%, even with efforts to mitigate climate change. This is because global temperatures are forecast to increase under both mitigated and unmitigated scenarios.

These predicted declines are in addition to the huge losses of forest already caused by ongoing deforestation throughout the island.

It looks as if the damage has already been done.

Climate change, a major threat

The results of our research highlight that climate change is indeed a major threat to Madagascar’s forests and likely other ecosystems worldwide. These findings are deeply concerning for the survival of Madagascar’s animals and plants, many of which depend entirely on forest habitat.

Not only will climate change decrease the size of existing forests, changes in temperature and rainfall will also affect the amount of fruit that trees produce.

A Lemur on tree in the forest. — Madagascar lemurs and other animal and plant species may become extinct if the forests disappear.
Rijasolo/AFP

Many of Madagascar’s animals, such as its lemurs, rely heavily on fruit for food. Changes in fruit availability will have serious impact on the health, reproductive success and population growth of these animals. Some animals may be able to adapt to changes in climate and habitat, but others are very sensitive to such changes. They are unlikely to survive in a hot, arid environment.

This will also have serious knock-on effects for human populations that depend on forests and animals for eco-tourism income. Approximately 75% of Madagascar’s population depends on the forest and subsistence farming for survival, and the tourism sector contributes over US$600 million towards the island’s economy annually.

To ensure that Madagascar’s forests survive, immediate action is needed to end deforestation, protect the remaining patches of forest, replant and restore forests, and mitigate global carbon emissions. Otherwise these remarkable forests will eventually disappear, along with all the animals and plants that depend on them.

——————————

This blog is written by Daniel Hending, Postdoctoral Research Assistant Animal Vibration Lab, University of Oxford and Cabot Institute for the Environment member Marc Holderied, Professor in Sensory Biology, University of Bristol. This article is republished from The Conversation under a Creative Commons license. Read the original article.

Marc Holderied

Detectable impacts of Climate Change in the UK; a new review for the next Climate Change Risk Assessment

Posted on January 17, 2023March 29, 2023 by janet.crompton

2022 was another year of “unprecedented” weather. Provisional figures indicate that it was the warmest so far recorded, with almost every month hotter than average. Much of the country had a notably mild New Year, despite the cold snap in mid-December. This was preceded by the third warmest autumn on record, and that by a scorching summer, with the hottest day ever recorded in July. But summer’s heat waves were also accompanied by a rise in the number of daily deaths across the country. People around the world are becoming increasingly more aware of events like these, and their impact in the UK is particularly concerning amidst the ongoing cost-of-living, energy, and NHS crises.

Aerial view of the Wennington wildfire, London, 19 July 2022. Source: Harrison Healey, Wikimedia Commons (CC BY 3.0).

Ahead of the Fourth UK Climate Change Risk Assessment (CCRA4), the Climate Change Committee (CCC) are asking what we know about the impact of past and present climate change on natural and human systems here in the UK specifically. At the global level, the 2021 IPCC sixth assessment working group I (AR6 WGI) report concluded: “It is unequivocal that human influence has warmed the atmosphere, ocean and land.” This single sentence has been informed by decades of research by people at the cutting edge of climate science, and the evidence to support it has grown stronger in every IPCC report since they began. The report goes on to say: “Human-induced climate change is already affecting many weather and climate extremes in every region across the globe.” In last year’s follow-up AR6 WGII report on impacts, adaptation, and vulnerability, an extensive assessment of the science led to the conclusion that the magnitude and proliferation of extremes caused by human-induced climate change were having widespread, adverse impacts on both nature and people. Last summer’s heatwaves, and the concurrent dangers to health, homes, and the environment, were a graphic illustration of the nature of such human-induced impacts.

The study of impacts that informed this conclusion is the remit of climate scientists who specialise in “detection and attribution”. This is about looking at what is changing around us and being able to pinpoint the cause(s) – and particularly, whether human-induced climate change is at the root. To inform CCRA4, the CCC have commissioned a joint Bristol and Exeter University team to conduct a comprehensive review of the detection and attribution of climate change in the UK. The first part will cover the detection and attribution of weather and climate changes in the UK, relevant to specific “Climate Impact Drivers”. The second will cover attribution of impacts on societal, infrastructural, economic, and biodiversity sectors. We aim to find out what studies have been done so far, where the gaps are, and whether they can be filled, or if they would require substantial new methodological or data advances. We aim to identify variables which are key drivers of multiple impacts, and, importantly, where further attribution analysis is needed – especially when the impacts are critical for UK risk.

Detection and attribution is a rapidly evolving field, with focus only relatively recently moving from meteorological attribution (e.g., weather extremes) to impact attribution (e.g., consequences for humans and ecosystems). Our systematic review of the literature and final report will be key to tying it all together, especially with the UK focus required by the CCC. But to be able to present the most up-to-date findings, and thus make informed recommendations, we need to ensure that we have considered all relevant studies. So, if you, or someone you know, has published on this topic – whether UK specific or not – we’d like to know about it! Help shape and inform the next UK Climate Change Risk Assessment.

————————-

This blog was written by Regan Mudhar, Professor Dann Mitchell (University of Bristol), Professor Richard Betts and Professor Peter Stott (University of Exeter/UK Met Office).

Four ways winter heatwaves affect humans and nature

Posted on January 11, 2023April 14, 2023 by janet.crompton

Temperature anomaly in Europe, Jan 1. Much of the continent was 10°C or more (dark red and grey) above the long-term average.
WX Charts, CC BY-NC

An extreme winter heatwave meant countries across Europe experienced a record-breaking New Year’s Day. New daily temperature records for the month of January were set in at least eight countries: Belarus, Czechia, Denmark, Latvia, Liechtenstein, Lithuania, Netherlands and Poland.

In many cases the temperatures were not just breaking the old highs, but smashing them by massive margins. On a typical January day in Warsaw, Poland, temperatures would barely go above freezing, yet the city recently experienced 19℃, breaking the previous January high by 5.1℃.

New January records were set at thousands of individual stations in many other countries such as 25.1℃ at Bilbao airport in Spain, 0.7℃ hotter than the previous record set only last year. Large areas of central and Eastern Europe experienced temperatures 10℃ to 15℃ warmer than average for this time of year – and that has persisted through the week.

When Europe experienced extreme heat in July of last year, more than 20,000 died. Fortunately winter heatwaves are much less deadly, but they can still affect both human society and natural ecosystems in many ways.

1. Less energy is needed

In Europe deaths due to cold weather vastly outweigh those caused by extreme high temperatures – in the UK there are ten times more. Warmer winters will reduce this excess mortality and, with the current cost-of-living crisis, many will have been relieved that a heatwave meant less energy was needed to heat their homes.

Electricity demand is influenced by things like the time of day, the day of the week and socio-economic factors like the COVID pandemic or the war in Ukraine. The weather also makes a difference. For example, in Poland and the Netherlands demand was noticeably lower than average, especially since January 1 was a Sunday. The extent of the heatwave also meant countries could refill some of their winter gas reserves, or large batteries.

Energy consumption in Poland December 28 to January 5. The red line shows the 2022-2023 heatwave period, and the grey lines show available data from 2015-2022.
Hannah Bloomfield / data: transparency.entsoe.eu, Author provided

2. Reduced yields for some crops

Winter warm spells don’t always have such a positive impact though. For instance a lack of snow in the mountains affects agriculture and can reduce crop yield, since snow creates an insulating blanket that prevents frost from penetrating into the soil. This means snow can actually increase soil moisture more than rainfall, thus improving growing conditions later in the season.

The big snow melt in spring time replenishes reservoirs and allows hydroelectricity generation, but unexpected snow melt can lead to flooding. Changes to the timings of these events will require preparation and adaptation to enable a steady supply of water to where we need it.

Warmer temperatures will create longer growing seasons in many regions. This is not always the case though. A recent study showed that for alpine grasslands an earlier growing season (the point when snow has melted entirely) leads to ageing and browning of the grasses in the later part of the summer.

3. The snow economy is in trouble

The heatwave caused ski resorts across the Alps to close in what should be their busiest time of year. In January the slopes would be expected to have a good covering of snow – but instead we saw green grassy fields.

This hits the local economy where many people rely on winter sports tourism. Events such as the Adelboden alpine ski World Cup are relying on artificial snow, which comes with a further environmental cost increasing the carbon footprint of ski resorts and requiring a large water supply. Indeed, the Beijing winter Olympics used the equivalent of daily drinking water for 900 million people to generate the artificial snow it required.

4. Animals out of sync with the climate

We humans are perhaps fortunate, as we are able to adapt. Some ski resorts have already opened mountain bike trails in winter to offer alternative tourism, but wildlife and ecosystems cannot adjust so rapidly.

In the mountains many species, such as ptarmigan and mountain hares, change their colouring for winter to camouflage in the white snow. The timing of this change is determined by length of day – not the temperature or amount of snow. These creatures are at greater risk of being preyed on when it is warmer.

White rabbit, brown background — Mountain hares are dressed for a climate that has changed.
Mark Medcalf / shutterstock

Over the past century heat extremes in Europe have increased in intensity and frequency. Both the general warming and heatwave events have been firmly attributed to humans.

Future projections suggest these trends will continue and heatwaves in both summer and winter will get hotter, last longer, and occur more often. We need to learn to adapt for these changes in all seasons and think about the impacts on everyone – and everything – on our planet.

—————————-

This blog is written by Cabot Institute for the Environment members Dr Vikki Thompson, Senior Research Associate in Geographical Sciences, University of Bristol and Dr Hannah Bloomfield, Postdoctoral Researcher in Climate Risk Analytics, University of Bristol. This article is republished from The Conversation under a Creative Commons license. Read the original article.

After COP27, is 1.5C still alive?

Posted on December 2, 2022April 16, 2023 by janet.crompton

Try booking a train on Boxing Day in the UK and you’ll soon find out that none are running. Well, not entirely. One small railway line managed by indomitable Gauls still holds out: The Eurostar. And airports are still being served as plains are still flying. Obvs. If this is not just the present, but also our future, then Mia Mottley, Prime Minister of Barbados, is right: “We’re at 1.2 degrees now. If in 5 years we’re at 1.5, then we’re…. we’re…. I won’t use that word now.”

Apologies, I got carried away. Back to planes (flying), trains (not running) and automobiles (driving). These are symptomatic of the mess we’re in, but nothing compared to the mess we’re heading towards. And nothing compared to the mess others already find themselves in. If these current trends continues the number of refugees is set to increase from 21m in 2022 to 1bn in 2050 (Mia Mottley again). Many originate from Africa which is responsible for only 4% of global emissions (and 2% of historic emissions) and home to 600m without access to electricity.

While inanimate capital moves freely across borders, refugees are increasingly prevented from doing so. As their poverty and desperation grows in a warming world, their cost of borrowing increases as the World Bank uses per capita income as a proxy for borrowing conditions. Consequently, such countries (Least Developed Countries – LDCs) borrow at 12-14% while rich countries (the G7) borrow at 1-4%. According to Indian economist Joyashree Roy, these countries need 7% growth per year to escape their plight but if they are borrowing at +10% cost of capital, this growth will not be powered by renewables.

Neither will the focusing on the supply of renewables alone deliver Sustainable Development Goals (SDGs). Demand-side interventions are necessary to shift investment patterns and create new economic opportunities that are synergistic with SDGs. But all this depends on infrastructure access and empowerment to make the right choices, which in turn are determined by the flow of finance. To put on track for 1.5C, these flows need to quadruple to $4-6trn per year, according to Macky Sall, Senegalese President and current Chairperson of the African Union. IPCC Chair Hoesung Lee, goes one step further: access to capital is the key determinant of limiting global warming to 1.5C. Concessional access to finance was provided during COVID, as Mia Mottley pointed out, so why can it not be provided to prevent climate catastrophe?

Dr Colin Nolden (left) at COP27 with IPCC Chair Hoesung Lee and Dr Alix Dietzel

On the plus side, outgoing COP26 President Alok Sharma suggests that 90% of global emissions are covered by a net zero target. Almost 1/3rd of the global population who accumulate 55% of global GDP are covered by Emissions Trading Schemes, according to Stefano de Clara, Head of the International Carbon Action Partnership. Then again, the current average carbon price stands at $6/t. This needs to increase to $75/t by 2030 to limit warming to 2C, not to mention 1.5C, according to Dora Benedek from the International Monetary Fund.

Without such a massive increase in the cost of carbon, emissions are expected to be only 12% (6GtCO2eq) lower in 2030 compared to today. What about magic??, you might interject at this point. Current Carbon Capture and Storage (CCS) and Direct Air Capture (DAC) capacities amount to around 4 hours of global emissions and are projected to amount to around 16 hours in 2030, according to Sven Teske from the University of Technology Sydney. To keep 1.5C alive, we need to reduce emissions by 30-50% in by 2030 (Dora Benedek again). So yes to magic, but only within the bounds of Kate Raworth’s famous doughnut.

And it’s both sides of that tasty doughnut that we need to bear in mind. On the outside, quick wins are possible regarding methane emissions which are responsible for around 0.5C of the 1.2C we stand above pre-industrial levels. Around 0.1C of warming can be addressed by cutting gas flaring and coal related methane emissions at no cost, according to US Deputy Climate Envoy Richard Duke. Addressing such emissions deliver invaluable co-benefits on the inside. 15% of all deaths (7million a year) are due to polluted air, according to Jane Burston of the Clean Air Fund. Companies are having to pay a pollution premium to attract talent to polluted cities.

It’s both the out and the in-side of the doughnut we need to focus on for a just transition to happen. According to Heike Henn, of Germany’s Federal Ministry for Economic Affairs and Climate Action and whatnot, Article 6 is emerging as the mechanism to allocate those $100bn/a finance pledged in Paris which never materialised as well as the trillions needed to implement NDCs (Nationally Determined Contributions) and SDGs.

Not Article 6.2 though, which requires adjustments in GHG registries upon the transfer of a carbon credits (Internationally Transferrable Mitigation Outcome – ITMO) and is already seeing emerging economies lowering ambition in their NDCs. Article 6.4 is what I’m talking about. Although it will take years to be operationalised, its infrastructure is being developed as we speak. The Climate Action Data Trust, for example, can significantly lower transaction costs of carbon market transactions through automated Measurement, Reporting and Verification (MRV) and tokenisation to create digital carbon assets.

Now it’s down to ambitious countries to form alliances and agree on a sharing mechanism to convert the 1.5C target into demand for mitigation action distributed dynamically over time, and measure achievement and contribution using Article 6.4. “Getting to net zero is a heroic task”, according to Dirk Forrister of the International Emissions Trading Association, “and you won’t get there by going alone”.

Where does this leave 1.5C? “I find it hard to stay optimistic”, said Nichola Sturgeon on day 1 of COP27. I echo this sentiment. Yet we need to remind ourselves that the combined net zero targets, if implemented, can limit warming to 1.7C and increase, yes INCREASE, global GDP by 0.4% per year, according to Fatih Birol from the IEA. If we can’t sort this out, bins will be burning.

———————————

This blog was written by Cabot Institute for the Environment member Dr Colin Nolden, Bristol Law School, University of Bristol.

Colin Nolden

COP27: What really happened on finance, justice and Loss and Damage?

Posted on December 2, 2022April 16, 2023 by janet.crompton

The Cabot Institute for the Environment sent three delegates to the recent Conference of the Parties 27 (COP27). Drs Alix Dietzel (Sociology, Politics and International Studies); Colin Nolden (Bristol Law School); and Rachel James (Geographical Sciences) were present for most of the first week and Colin was there for the full two weeks. As the Institute has observer status with the United Nations Framework Convention on Climate Change, Alix, Rachel and Colin had the chance to engage with policy makers and climate policy experts from around the world to help promote climate action which is informed by the best evidence and research.

We asked them to give an update on their experience at COP27 and as a result, whether the pledges made at COP27 would mean that 1.5C is still achievable.

Drs Colin Nolden and Alix Dietzel at COP27.

Climate finance – Dr Colin Nolden

Colin’s research interests span sustainable energy policy, regulation and business models and interactions with secondary markets such as carbon markets and other sectors such as mobility. COP27 was an opportunity for him to talk directly to policymakers about implementing the Paris Agreement and to people directly affected by climate policy decisions.

Here are Colin’s post-COP thoughts:

“Alongside Loss and Damage, the main issue discussed at COP is climate finance for decarbonisation. The $100bn/yr pledged in Paris has never materialised and to add injury to insult, rich countries can borrow at 4%, whereas poor countries borrow at 14%, as Mia Motley, Prime Minister of Barbados, pointed out in her speech on Day 1. Under these conditions, investments in fossil fuel infrastructures pay off, but investments in renewables do not. An endless number of panel discussions and side events on ‘climate finance’ and ‘accelerating the clean energy/net zero transition’ are testament to this gap.

“Article 6 of the Paris Agreement is a mechanism to overcome this funding gap by providing the legal foundation to finance decarbonisation projects in a country in exchange for carbon credits provided by another. Whether these should lead to according adjustments in emissions inventories, as is the case under bilateral agreements using Article 6.2, is controversial. How Article 6.4 will deal with this issue is still unclear and is unlikely to be agreed on at successive COPs. Negotiations on Article 6 will determine the climate credit and finance architecture for years to come.”

Climate justice – Dr Alix Dietzel

Alix is Associate Director for Impact and Innovation at the Cabot Institute for the Environment and an environmental justice scholar. Her role at COP27 was to observe the negotiations and critically reflect on whose voices were heard and whose were left out of the discussion, as well as concentrating on whether topics such as Loss and Damage and just transition were being given adequate space and time during the negotiations.

Dr Alix Dietzel at COP27.

Here are Alix’s reflections from COP27:

“Despite much excitement over a new Loss and Damage fund, there is backsliding on commitments to lower emissions and phasing out fossil fuels. As an academic expert in just transition who went along this year hoping to make a difference, I share the anger felt around the world about this outcome.

“Attendance at COPs is strictly regulated. Parties (negotiating teams), the media, and observers (NGOs, IGOs, and UN Agencies) must all be pre-approved. Observers have access to the main plenaries and ceremonies, the pavilion exhibition spaces, and side-events. The negotiation rooms, however, are largely off limits. Most of the day is spent listening to speeches, networking, and asking questions at side-events. The main role of observers, then, is to apply indirect pressure on negotiators, report on what is happening, and network. Meaningful impact on and participation in negotiations seemed out of reach for many of the passionate people I met.

“It has long been known that who gets a say in climate change governance is skewed. As someone working on fair decision making as part of just transition, it is clear that only the most powerful voices are reflected in treaties such as the Paris Agreement. Despite being advertised as ‘Africa’s COP’, COP27 has further hampered inclusion. The run up was dogged by accusations of inflated hotel prices and concerns over surveillance, no chance to organize protests, and warnings about Egypt’s brutal police state.

“Arriving in Sharm El Sheik, there was an air of intimidation starting at the airport, where military personnel scrutinized passports. Police roadblocks featured heavily on our way to the hotel, and military officials surrounded the COP venue the next morning. Inside the venue, there were rumours we were being watched and observers were urged not to download the official app. More minor issues included voices literally not being heard due to unreliable microphones and the constant drone of airplanes overhead. Food queues were huge, and it was difficult to access water to refill our bottles. Sponsored by Coca Cola, we could buy soft drinks. Outside of COP, unless I was accompanied by a man, I faced near constant sexual harassment, hampering my ability to come and go freely.

“Who was there and who was most represented at COP27 also concerned me. The United Arab Emirates (UAE) registered the largest party delegation with more than 1,000 people, almost twice the size of the next biggest delegation, Brazil. Oil and gas lobby representatives were registered in the national delegations of 29 different countries and were larger than any single national delegation (outside of the UAE). At least 636 of those attending were lobbyists for the fossil-fuel industry. Despite the promise that COP27 would foreground African interests, the fossil lobby outnumbers any delegation from Africa. These numbers give a sense of who has power and say at these negotiations, and who does not.

“All this to say, I am not surprised at the outcomes. There is some good news in the form of a new fund for Loss and Damage – but there is no agreement yet on how much money should be paid in, by whom, and on what basis. More worryingly, the outcome document makes no mention of phasing out fossil fuels, and scant reference to the 1.5C target. Laurence Tubiana, one of the architects of the Paris Agreement, blamed the host country, Egypt, for the final decision.

“COP27 produced a text that clearly protects oil and gas petro-states and the fossil fuel industry. The final outcomes demonstrate that despite the thousands who were there to advocate for climate justice, it was the fossil fuel lobby who had most influence. As a climate justice scholar, I am deeply worried about the processes at COPs, especially given next year’s destination: The United Arab Emirates. Time is running out and watered-down commitments on emissions are at this stage deeply unjust and frankly dangerous.”

Loss and Damage – Dr Rachel James

Rachel is a climate scientist, focusing on African climate systems and developing climate science to inform and advance climate change policy. Her previous research has been designed to progress international climate policy discussions, including the COP process, and she has analysed the impacts of global mitigation goals, comparing different warming scenarios (1.5°C, 2°C and beyond). At COP27, she engaged in adaptation discussions, to learn more about how science can support national adaptation planning, to guide her new research programme “Salient”, a UKRI Future Leaders Fellowship to improve climate information for adaptation, primarily in southern Africa.

Dr Rachel James (fourth from right) at COP27.

In her previous work, Dr James has also looked at how science can support policy discussions about ‘Loss and Damage’, from climate change, and at COP27 she followed discussions on Loss and Damage, as well as taking part in a workshop to establish a network of African researchers focusing on Loss and Damage. Rachel reflects on her experience of COP and the Loss and Damage discussions:

“The COP is now a huge event, with hundreds of discussions happening simultaneously, and many thousands of people, (almost) all pushing for climate action, and acting on it in their own ways. There are lots of things going on, deals being struck, collaborations forming, alongside the official UNFCCC business.

“This was supposed to be the “COP of implementation”, as the Paris Agreement and the rulebook are already in place. Some said we were largely beyond negotiation.

“However, the Global South came ready to negotiate, particularly on Loss and Damage. They wanted a finance facility on Loss and Damage to be established. Negotiations began in the weekend before the COP, and – after negotiating all night with no food – the developing countries succeeded in getting this onto the formal agenda.

“Over the two weeks of the COP, my perception was that there was a huge shift on Loss and Damage. Once it was on the official agenda, it was much easier to talk about. It has been a very contentious issue. Broadly, the most vulnerable countries have called for mechanisms to address the fact that they are, and will continue to, experience loss and damage from climate change impacts like sea level rise and extreme weather. Those countries who have emitted the most fear this could lead to unlimited liability. When I first started working on it I’d often get a worried look when I mentioned the topic.

“In a side event during the first week at Sharm El Sheikh, I heard someone say “some magic has happened” and we can now talk about this in the mainstream. We also saw a series of announcements from countries committing finance for Loss and Damage. Then, finally, after two weeks of negotiations ran into extra time, countries agreed to establish a fund for Loss and Damage.

“This was a huge victory for the developing countries. Lots of questions remain about how it will work, who will pay into it, and who will benefit, but nevertheless it marks a big step. Developing countries (especially AOSIS, the Alliance of Small Island States) have been working on this for decades. The negotiators work so hard, often into the night, it’s incredible.

“My overall view is that COP continues to be a difficult process, but it is shifting, maybe substantially. Many view COP as a talk shop and suggest it’s a waste of time, but I disagree. Although the process is tortuous, slow, and frustrating, it is the best one we have, and still vital. Progress is way too slow but there is progress. Every country is represented, and we don’t have any other process on climate change where that is the case. The developing countries have power in numbers at the COP that I am not sure they have in any other forum on climate change.”

Dr Alix Dietzel (fourth from right on the back row) at COP27

Is 1.5C still alive?

Colin: “The International Energy Agency expects fossil fuel demand to peak as early as 2025. However, with all countries harbouring exploitable fossil fuel resources racing to extract them (with our former Secretary of State for Business, Energy and Industrial Strategy Rees-Mogg vowing in September 2022 to “squeeze every last drop of oil” out of the North Sea) and key initiatives such as the Glasgow Financial Alliance for Net Zero failing to deliver on their promises, fossil fuels will not be phased out anytime soon.

“At the same time, pinning our hopes on Carbon Capture and Storage (CCS) is misguided as current capacities amount to four hours of global emissions and International Energy Agency projections suggest that capacities in 2030 will amount to 16 hours of emissions. This implies that in the absence of a sustained global financial commitment towards demand reduction or sustainable supply, limiting average global temperature rise to 1.5 above will be very difficult indeed.”

Rachel: “A key goal in Glasgow and in Sharm El Sheikh has been to keep 1.5°C alive. Some countries were attempting to backslide on mitigation goals during the final days, but in the end 1.5°C remained in the text. It’s disappointing that we didn’t see an increase in ambition from Glasgow, but 1.5°C is still there – even if “on life support”, as noted by Alok Sharma.

“It’s easy for us to do an academic analysis and speculate as to whether or not we think 1.5°C is politically feasible. But the IPCC has spelled it out clearly: every fraction of a degree of warming matters. What’s important is that we increase ambition to reduce emissions, and we phase out fossil fuels, so that we can limit global warming as much as possible.”

———————————-

This blog is written by Cabot Institute for the Environment members Dr Alix Dietzel, Dr Colin Nolden, Dr Rachel James and Amanda Woodman-Hardy.

Insects will struggle to keep pace with global temperature rise – which could be bad news for humans

Posted on October 4, 2022March 29, 2023 by janet.crompton

Animals can only endure temperatures within a given range. The upper and lower temperatures of this range are called its critical thermal limits. As these limits are exceeded, an animal must either adjust or migrate to a cooler climate.

However, temperatures are rising across the world at a rapid pace. The record-breaking heatwaves experienced across Europe this summer are indicative of this. Heatwaves such as these can cause temperatures to regularly surpass critical thermal limits, endangering many species.

In a new study, my colleagues and I assessed how well 102 species of insect can adjust their critical thermal limits to survive temperature extremes. We found that insects have a weak capacity to do so, making them particularly vulnerable to climate change.

The impact of climate change on insects could have profound consequences for human life. Many insect species serve important ecological functions while the movement of others can disrupt the balance of ecosystems.

How do animals adjust to temperature extremes?

An animal can extend its critical thermal limits through either acclimation or adaptation.

Acclimation occurs within an animal’s lifetime (often within hours). It’s the process by which previous exposure helps give an animal or insect protection against later environmental stress. Humans acclimate to intense UV exposure through gradual tanning which later protects skin against harmful UV rays.

One way insects acclimate is by producing heat shock proteins in response to heat exposure. This prevents cells dying under temperature extremes.

A ladybird drinking a speck of water on a narrow leaf. — Insects in warmer environments develop fewer spots to reduce heat retention.
mehmetkrc/Shutterstock

Some insects can also use colour to acclimate. Ladybirds that develop in warm environments emerge from the pupal stage with less spots than insects that develop in the cold. As darker spots absorb heat, having fewer spots keeps the insect cooler.

Adaptation occurs when useful genes are passed through generations via evolution. There are multiple examples of animals evolving in response to climate change.

Over the past 150 years, some Australian parrot species such as gang-gang cockatoos and red-rumped parrots have evolved larger beaks. As a greater quantity of blood can be diverted to a larger beak, more heat can be lost into the surrounding environment.

A colourful red-rumped parrot perched on a branch. — The red-rumped parrot has evolved a larger beak to cope with higher temperatures.
Alamin-Khan/Shutterstock

But evolution occurs over a longer period than acclimation and may not allow critical thermal limits to adjust in line with the current pace of global temperature rise. Upper thermal limits are particularly slow to evolve, which may be due to the large genetic changes required for greater heat tolerance.

Research into how acclimation might help animals survive exceptional temperature rise has therefore become an area of growing scientific interest.

A weak ability to adjust to temperature extremes

When exposed to a 1℃ change in temperature, we found that insects could only modify their upper thermal limit by around 10% and their lower limit by around 15% on average. In comparison, a separate study found that fish and crustaceans could modify their limits by around 30%.

But we found that there are windows during development where an insect has a greater tolerance towards heat. As juvenile insects are less mobile than adults, they are less able to use their behaviour to modify their temperature. A caterpillar in its cocoon stage, for example, cannot move into the shade to escape the heat.

Exposed to greater temperature variations, this immobile life stage has faced strong evolutionary pressure to develop mechanisms to withstand temperature stress. Juvenile insects generally had a greater capacity for acclimating to rising temperatures than adult insects. Juveniles were able to modify their upper thermal limit by 11% on average, compared to 7% for adults.

But given that their capacity to acclimate is still relatively weak and may fall as an insect leaves this life stage, the impact is likely to be limited for adjusting to future climate change.

What does this mean for the future?

A weak ability to adjust to higher temperatures will mean many insects will need to migrate to cooler climates in order to survive. The movement of insects into new environments could upset the delicate balance of ecosystems.

Insect pests account for the loss of 40% of global crop production. As their geographical distribution changes, pests could further threaten food security. A UN report from 2021 concluded that fall armyworm populations, which feed on crops such as maize, have already expanded their range due to climate change.

A damaged corn crop following an attack by fall armyworms. — The fall armyworm is a damaging crop pest which is spreading due to climate change.
Alchemist from India/Shutterstock

Insect migration may also carry profound impacts on human health. Many of the major diseases affecting humans, including malaria, are transmitted by insects. The movement of insects over time increases the possibility of introducing infectious diseases to higher latitudes.

There have been over 770 cases of West Nile virus recorded in Europe this year. Italy’s Veneto region, where the majority of the cases originate, has emerged as an ideal habitat for Culex mosquitoes, which can host and transmit the virus. Earlier this year, scientists found that the number of mosquitoes in the region had increased by 27%.

Insect species incapable of migrating may also become extinct. This is of concern because many insects perform important ecological functions. Three quarters of the crops produced globally are fertilised by pollinators. Their loss could cause a sharp reduction in global food production.

The vulnerability of insects to temperature extremes means that we face an uncertain and worrying future if we cannot curb the pace of climate change. A clear way of protecting these species is to slow the pace of climate change by reducing fossil fuel consumption. On a smaller scale, the creation of shady habitats, which contain cooler microclimates, could provide essential respite for insects facing rising temperatures.