• Energy Research

We report the results of a structured expert elicitation to identify the most likely types of potential food system disruption scenarios for the UK, focusing on routes to civil unrest. We take a backcasting approach by defining as an end-point a societal event in which 1 in 2000 people have been injured in the UK, which 40% of experts rated as “Possible (20–50%)”, “More likely than not (50–80%)” or “Very likely (>80%)” over the coming decade. Over a timeframe of 50 years, this increased to 80% of experts. The experts considered two food system scenarios and ranked their plausibility of contributing to the given societal scenario. For a timescale of 10 years, the majority identified a food distribution problem as the most likely. Over a timescale of 50 years, the experts were more evenly split between the two scenarios, but over half thought the most likely route to civil unrest would be a lack of total food in the UK. However, the experts stressed that the various causes of food system disruption are interconnected and can create cascading risks, highlighting the importance of a systems approach. We encourage food system stakeholders to use these results in their risk planning and recommend future work to support prevention, preparedness, response and recovery planning.

Record-breaking high temperatures were experienced across the United Kingdom during summer 2022. The impacts of these extreme climatic conditions were felt across the food system, including increased energy costs for cold storage, the failure of refrigeration systems in numerous retail facilities, and impacts on livestock including heat stress. Future climate projections indicate an increased likelihood and duration of extreme high temperatures like those experienced in 2022. Learning from the impacts of the 2022 heatwave on the United Kingdom food system can help identify adaptations that build resilience to climate change. We explore the impacts through two case studies (United Kingdom poultry and wheat sectors), discuss potential adaptation options required for a climate-resilient, net-zero United Kingdom food system and consider future research needs. United Kingdom chicken meat production was 9% lower in July 2022 than July 2021; in contrast, energy costs increased for both production and refrigeration. Potential heatwave adaptation measures for poultry include transitioning to heat tolerant chicken breeds, lower stocking density, dehumidification cooling and misting systems, nutritional supplements, and improving retail refrigeration resilience and efficiency. United Kingdom wheat yields were 8% higher in 2022 than the 2017–2021 average. Increases were observed in every United Kingdom region but were least in the South and East where the heatwave intensity was strongest. Future adaptation measures to avoid negative impacts of summer heat stress on winter wheat could include earlier maturing and heat/drought tolerant varieties, earlier autumn sowing, targeted irrigation for drought around anthesis, and soil and water conservation measures.

Abstract Precipitation within extratropical cyclones is very likely to increase towards the end of the century in a business-as-usual scenario. We investigate hourly precipitation changes in end-of-century winter storms with the first km-scale model ensemble covering northwest Europe and the Baltic region. This is an ensemble that explicitly represents convection (convection permitting models (CPMs)). Models agree that future winter storms will bring 10%–50% more precipitation, with the same level of light precipitation but more moderate and heavy precipitation, together with less frequent frozen precipitation. The warm sector precipitation rates will get closer (up to similar) to those in present-day autumn storms, along with higher convective available potential energy and convective inhibition, suggesting more convection embedded in storms. To the first order, mean hourly precipitation changes in winter storms are driven by temperature increase (with little relative humidity changes) and storm dynamical intensity (more uncertain), both captured by regional climate models (RCMs). The CPMs agree with this, and in addition, most CPMs show more increase in intense precipitation in the warm sector of storms compared to their parent RCM.

Abstract Anthropogenic aerosol emissions are expected to change rapidly over the coming decades, driving strong, spatially complex trends in temperature, hydroclimate, and extreme events both near and far from emission sources. Under-resourced, highly populated regions often bear the brunt of aerosols’ climate and air quality effects, amplifying risk through heightened exposure and vulnerability. However, many policy-facing evaluations of near-term climate risk, including those in the latest Intergovernmental Panel on Climate Change assessment report, underrepresent aerosols’ complex and regionally diverse climate effects, reducing them to a globally averaged offset to greenhouse gas warming. We argue that this constitutes a major missing element in society’s ability to prepare for future climate change. We outline a pathway towards progress and call for greater interaction between the aerosol research, impact modeling, scenario development, and risk assessment communities.