Policymakers must take long-term decisions despite limited data about the scale, scope and dynamics of the climate change. Seemingly attractive policies, like a rapid transition to electric vehicles, might not deliver the benefits expected, while other under-appreciated interventions could have co-benefits, such as simultaneously achieving climate goals with equity and inclusion outcomes. Decisions around financial incentives and market structures, for example pricing carbon or putting economic value on enhanced ecosystem service provision by restoring and conserving forests, must also be taken based on data-driven evidence, together with robust modelling and projections to show likely future scenarios.
Understanding chemicals, plastics and clean air
While carbon emissions are central to climate change discourse, the pollution crisis is broader. A toxic slew of pollutants from chemicals and plastics affects our water, food, and air. Microplastics, for instance, were recently found in human lungs for the first time.
Governments and international bodies rely on scientific advice to understand the current scale of chemical, plastics and air pollution and make optimal regulatory choices to restrict or phase out substances that are toxic to human and ecosystem health, without over-reaching and constraining the adoption of useful products. The research tools involved in producing that evidence and data are being revolutionised thanks to advances in genomics, metabolomics, quantitative genetics, data science and toxicology.
Iseult Lynch, Professor of Environmental Nanosciences, chairs the Hazardous Substances Advisory Committee (HSAC) of Defra, its agencies and the devolved governments, which also includes Birmingham’s John Colborne, Professor of Environmental Genomics, and Stuart Harrad, Professor of Environmental Chemistry. HSAC provides expert advice to the UK government on protecting human health and the environment from hazardous materials, including nanomaterials, microplastics and chemicals. This advice forms a critical contribution to the UK’s national Chemicals Strategy. This is part of a 25-year national environment plan, by enabling a transition to new and advanced methodologies for hazard and risk assessment.
Part of HSAC’s work, Professor Lynch explains, is to filter the evidence and provide guidance to government on the decisions most warranting of their attention. This includes horizon-scanning, using the ‘Delphi’ method, an inclusive decision-making methodology, which revealed an emerging priority among the scientific community to better understand the interplay of chemicals with each other and the environment, rather than viewing them in isolation.
“Amongst the scientists on HSAC, there is a real push to look beyond recognising chemicals individually and placing them in the broader context of how they interact and mix, alongside other stressors, such as climate change and biodiversity loss,” says Professor Lynch. The scientific community is also advocating for an intergovernmental panel for chemicals and waste. “At the moment,” says Professor Lynch, “existing chemicals legislation typically only asks ‘is it safe to go into a product?’, but not into what happens when a product is at its end of life as that comes under separate legislation. We need to think about the whole lifecycle and design materials and products with both safety and sustainability and circularity in mind.”
The committee is helping regulators make speedier decisions, such as by analysing chemicals in groups and using alternative evidential data points to measure the impacts of hazardous substances like computational rather than animal studies. “Where there are gaps in how fast those methods can be validated for use, and caution on the regulators side not to move too quickly, we need to find ways to cut through complexity, allow policymakers to take on board information and still make decisions,” argues Professor Lynch.
The Centre for Precision Toxicology, led by the University of Birmingham alongside 15 European and US organisations, is blending technology, science and law to establish a new cost-effective testing paradigm for chemical safety assessment — Precision Toxicology — that could revolutionise regulatory toxicology, replace animal testing, reduce uncertainty, and determine safety factors in assessing risks to human health.
Research at Birmingham is also addressing the multi-stressor challenge of chemical cocktails and climate stress, providing a scientific basis for updating standard regulatory testing guidelines for chemicals and advanced materials to better reflect the real-world challenges for species, ecosystems and pollutant mobility, to ensure preparedness for future climate scenarios.
- Decision makers should partner with the academic community to identify decisions most warranting of government attention. This should be based on scientific consensus and emerging trends and explore novel techniques for assessing toxicity and risk more precisely and rapidly.
- Avoid overly focusing on standardised (optimised) conditions for assessment of the (eco)toxicity of chemicals and their mixtures. This could miss the combined impacts of climate stress (such as increased temperature, water stress) and pollution on organisms and ecosystems.
- There is an urgent need to include higher temperature conditions into standardised ecotoxicity testing to identify at-risk organisms / ecosystems and prioritise mitigation strategies.
Similar research efforts – to more accurately quantify current pollution and support policymakers to best confront it – are underway in the field of air pollution. WM-Air, led by William Bloss, Professor of Atmospheric Science, is providing an improved understanding of air pollution sources and levels in the West Midlands. Funded by the Natural Environment Research Council (NERC), the project works in collaboration with over 20 cross-sector partners, applying environmental science expertise to improve air quality and health across the region. This work includes understanding air pollution sources, quantifying the benefits of policy options, and allowing individual interventions to be analysed against given air quality outcomes.
Professor Bloss is working with the West Midlands Combined Authority on modelling future air quality scenarios linked to net zero policy trajectories and optimising the resulting air quality co-benefits that result. Professor Bloss and his team are advising on an Air Quality Framework to help set a region-wide approach in the Midlands. “Air pollution doesn’t stop at the city boundary of Birmingham or Coventry,” he notes. As regulation around pollution tightens, the work of Professor Bloss and his team will be of increasing value as companies and organisations have to improve their performance by law rather than discretionary effort.
The UK’s Environment Act 2021, for instance, allows local authorities to designate other public sector bodies as ‘air quality partners’ if they are responsible for emissions, and to require them to develop a reduction strategy with recourse to the Secretary of State for those that fail. That has implications for a range of public bodies potentially including the NHS and National Highways. “We have been bringing this to their attention and identifying how much impact comes from an infrastructure or a fixed source industrial site,” says Professor Bloss.
The private sector also benefits from Birmingham’s air pollution research. Professor Pope’s research includes using low-cost air sensors to apportion air pollution to specific sources. This has been a useful tool for industry, sparking a collaboration with Dust Scan, an SME focusing on nuisance dust and air pollution from sites like construction and mining. Sensor data can provide deeper insight into not just overall pollution levels but underlying sources and causes and variations in different environmental and weather conditions. “The vision is not only to use these sensors to measure the concentration of air pollution, but also to be able say what is causing the pollution – we don’t just measure it but also attribute it,” says Professor Pope.
The collaboration was a result of Professor Pope’s work in East Africa, which a senior Dust Scan consultant, Gordon Allison, learned through his engagement with Birmingham as a guest lecturer on a Masters course on air pollution. “It showed how work in one country can cross boundaries rapidly and not always in the countries you might expect,” says Professor Pope. “It came out of blue-sky academic research – asking, can we get more information out of sensors? And it later became clear there is potential to be commercially useful”. These insights help us understand the optimal environmental conditions for potentially polluting activities. “You can be more proactive in decision-making in sectors like construction, about when you do what, where and when.”
- Use climate co-benefits – for example, cleaner air – to demonstrate there are health and environmental benefits from local actions to address the global carbon challenge, and so encourage early change.
Modelling climate futures
Future climate scenarios are shrouded in uncertainty, as different modelled temperature bands suggest varying ecological dynamics, such as the level of carbon capture by forests. Research at Birmingham’s Institute of Forest Research (BIFoR) is helping policymakers consider how future changes in climate and land use could inform decisions today.
Sami Ullah, Professor of Biogeochemistry, and a researcher at BIFoR, is spearheading research assessing whether forests will be able to capture the elevated levels of CO2 expected in the future. This research also explores whether the ‘CO2 capture potential’ of forests might be constrained by other factors such as the availability of nutrients and water and/or tree diseases under future climates.
Over the last five years, as part of BIFoR, the University has established a Free-Air Carbon Dioxide Enrichment (FACE) experiment within a mature native forest in Staffordshire. Researchers are exposing a mature oak-dominated woodland to CO2 at levels expected to be the norm by 2050. This ambitious, collaborative long-term research initiative (2016-2026) will produce findings to address fundamental uncertainties in the global carbon budgets of forests under future climates. This vital work will allow governments to take informed decisions about the role of forests in climate change mitigation.
BIFoR research has international dimensions. It has engaged with the recently announced FACE experiment in the Amazonian rainforest, through AmazonFACE, whose implications for development helped initiate UK government funding, through the Foreign, Commonwealth and Development Office (FCDO). BIFoR is also collaborating with the Australian-based EucFACE experiment, where mature eucalyptus trees are exposed to elevated CO2 levels in a Mediterranean-type temperate climate. These unique FACE experiments covering key global forest types will, by showing their likely CO2 capture performance in a future scenario, enable a more realistic assessment of the role of forests in carbon capture and climate change mitigation.
Professor Ullah believes governments are a natural partner to back long-term scientific data-gathering initiatives like BIFoR-FACE — and beneficiary of the resulting data. “It’s in the government’s interest to fund such projects as they have the responsibility to mitigate climate change and to provide a home to biodiversity, prevent flooding, and provide ecosystems that are important for human well-being,” says Professor Ullah. “And in terms of real decisions, such projects provide the government with the correct prediction and value of carbon credit that can go to the economic market.” Professor Ullah calls on governments to explore a global initiative inspired by the FACE program, to include other types of forests, such as boreal ecosystems and mangrove forests, so that “we could have a fuller picture of the nature-based solution for climate change mitigation”.
- Policymakers need to agree the optimum land cover percentages for ‘nature-based solutions’ at a national level. This will address climate change mitigation through restoration and conservation of forests.
- A percent ‘land per nation’ target can be an effective indicator of the wider targets to capture carbon and stop deforestation.
Professor Ullah is also working at the national level, as part of a panel of experts on the Defra Nutrient Management Expert Group. This focuses on regulation and policy recommendations regarding the use of fertilisers and nutrients in landscapes to sustain food production, protect water and air quality and improve soil health. It encompasses the burden of greenhouse gas emissions like nitrous oxide and atmospheric pollutants such as ammonia, and weighing human health and ecological implications, while protecting the quality of the water and biodiversity. “Nitrogen is the next carbon, and it has to be considered seriously,” says Professor Ullah. “It has implications for food security and net zero as well as for the environment. through air, water, and soils.”
Understanding the sustainability dynamics of fertiliser and nutrients in agriculture is particularly important for the UK, as it departs from EU agriculture legislation. “We are coming out of the EU Common Agricultural Policy in 2024/2025, so we will have to have our own regulations,” notes Professor Ullah. “We are trying to develop more sustainable management portfolio resources in nutrients to deliver multiple benefits, including reductions in greenhouse gas emissions, mitigations, and climate change.”
Professor David Hannah, Professor of Hydrology and UNESCO Chair in Water Sciences at the University of Birmingham, is engaged in policy engagement programmes — understanding future water security and risks to inform decision-making now. With increased frequency of hydrological extremes such as floods and drought across the world, it is crucial for governments to understand the evolving risk landscape and how choices made today can create risks tomorrow.
Based on an analysis of outcomes for global model intercomparison projects to the end of the century (2100), Professor Hannah says: “The greatest source of uncertainty is not between what climate model you use, but which hydrological model you run those climate models through to project future high and low flows. This tells us that we really need to better understand terrestrial hydrological processes to make projections of future extreme environments.
“The water cycle is a major variable impacting our climate future and is often referred to as the ‘climate connector’ as floods and droughts are the ways many people feel the impacts of climate change.”
Professor Hannah’s research has also identified the impact of changing land use and land cover on the terrestrial water cycle, and the resulting feedback loops as ecosystems become more alike through agriculture and development which tends to reduce biodiversity and variety in favour of monocultures. The largest uncertainties in hydrological projection are found typically in areas with the most significant water security challenges. One issue Professor Hannah identifies is the impact of changing land use and land cover on the terrestrial water cycle, specifically the changing plant-water interactions as we convert more land to agriculture for food supply. Lower levels of biodiversity and less diverse land cover limit the routing options of terrestrial water, compared to naturally vegetated landscapes, Hannah’s research has found. As a result, monocultures are more vulnerable to climate disturbances, and this could weaken the resilience of the planet’s terrestrial water cycle to stressors. Monocultures are less able to cope with climate extremes, such as droughts, because of their limited ability to respond to these stressors. “As you move from mixed land use like forests and pastures to cropping one thing, this results in the homogenization of the water cycle. More diverse environments are more resilient and less vulnerable to changing conditions,” Professor Hannah asserts.
One area where modelling is having a positive effect is in the work Professor Hannah is doing with Marine Scotland Science (MSS), part of Scottish Government, focusing on how trees can shade rivers, reducing solar radiation, and, in turn, protecting freshwater fish from rising temperatures anticipated in a warming climate. Wild Atlantic salmon is an industry worth £80 million a year. In collaboration with MSS, Professor Hannah has undertaken research producing numerical models of river temperatures at the national level for Scotland, which can be used to inform where streams are projected to see the highest eater temperature increases and thus, where riparian tree planting would have the greatest impact. This work culminated in an online tool where landowners could get a map of river basins with colour coding for hottest areas, which they can then use in planning applications for tree planting. This research is help decision makers pursue more targeted interventions. “We showed that with sparser planting, in more targeted locations, you can gain a bigger benefit that less strategic, larger-scale interventions,” says Professor Hannah. “Without such research evidence, you risk making interventions that aren’t as impactful.”
This research has international dimensions and relevance. The approach has been advocated by the inter-governmental conservation efforts of the North Atlantic Salmon Conservation Organisation (NASCO) review group and is now being replicated in other nations. Marine Scotland works to facilitate the achievement of NASCO’s international goals for sea life is and is part of aworking group seeking to improve aquaculture management and environmental performance, .
Scenario research — alternative pictures of possible futures and the pathways leading to them — can help us make sense of the complexity and uncertainty of the future, assisting decision-makers to design and implement policies to reduce and to adapt to negative effects of water extremes such as droughts, floods, and pollution.
Professor Hannah emphasises the importance of conducting scenario exercises in partnership with social actors, especially governments. This participatory scenario development raises awareness among policymakers of their risk trajectories and encourages them to focus on policies that work effectively in potential futures .
- Forecasting and scenario modelling can inform more targeted and precise interventions to harness nature with maximal impact.
- Modelling can reveal emergent risk factors such as the impact of monocultures on the water cycle.