Written evidence submitted by Professor Hannah Cloke, University of Reading

1. This evidence is submitted by Professor Hannah Cloke from the University of Reading. I research climate change adaptation, disaster risk management and forecasting and early warning of natural hazards such as floods and heatwaves.

Climate change and flooding

2. Climate change is already causing many types of floods to get worse, in the short-to medium term. On longer timescales in the future (in 5 to 20 years, and beyond), we are likely to see more extreme weather and more floods – and in areas that are not well adapted for them; for example, coastal flooding could reach further inland; river floods could occur faster and affect more people; and flash floods from intense rainfall can occur anywhere – including in cities.

3. Catastrophic floods such as those that hit Germany and other parts of Europe this summer could become much more frequent as a result of climate change through a combination of more intense downpours and slower moving storms1 .

4. In addition, compound flooding events – where surface water, river and coastal flooding occur simultaneously – are predicted to increase in the UK2.

5. The UK is not prepared for heavy rainfall events now, due to ageing urban drainage systems and poor planning of key infrastructure. We need to move faster to make critical infrastructure more resilient to flooding.

6. For example, flash floods caused by intense summer rainfall in London in summer 2021 caused homes, shops and businesses to flood; transport infrastructure (key roads, Underground stations, bus routes) were closed; health infrastructure (a hospital accident & emergency department) was inaccessible or forced to close. Floods of this nature cause water supply and sewerage system disruption.

7. We need a joined up approach to flood management. There remains fragmentation in terms of responsibilities for different types of flooding3

Planning and adapting through stronger regulation and guidance

8. Floods are inevitable and are getting worse as a result of climate change. But it is possible to prepare for them. Effective flood risk management needs to do many things, which may include

9. We urgently need to change the way we build in our cities, our towns and across our countryside. We need to make space for water, plan ahead, which means joining up thinking across all different parts of government.

Global flooding impacts on UK critical national infrastructure

10. While this inquiry focuses on UK critical infrastructure, it should be remembered that climate change impacts do not stop at national borders. Critical national infrastructure could easily be impacted, both directly and indirectly, by climate impacts overseas – for example, through extreme weather in British Overseas Territories or partner nations; through impacts on UK defence infrastructure located in or operated by UK allies; or by impacting global supply chains required for robust critical infrastructure.

11. For example, critical assets overseas that have a significant impact on UK supply chains – for food, medical supplies and other goods – are being affected by worsening floods due to changes to patterns of monsoons and tropical storms. The result of these impacts on vulnerable developing countries could impact large numbers of people, creating significant instability and driving political unrest and migration, which would further put pressure on the UK’s own critical infrastructure.

12. For example, record-breaking floods in China in summer 2021 highlighted the vulnerability of underground infrastructure such as tunnels and trains to floods caused by intense rainfall. Such events are possible now, and will become more likely in the future, even with aggressive reductions to greenhouse gas emissions.

Heatwaves/Forest Fires

13. The UK is not well prepared for heatwaves, which remain an almost invisible risk in the UK4. Communication over what UK residents should do, the support needed to make changes, and their capacity to enact those changes, is often lacking.

14. In turn, there is an inherent bias where research has traditionally focused too narrowly on the impacts of heatwaves on health and building sectors over other critical sectors, such as agriculture and food.

15. The record-breaking heatwaves and forest fires around the world in 2021 – including in Canada and around the Mediterranean – showed how heatwaves and fires can quickly emerge as life-threatening extremes from a background of gradual warming temperatures.

UK-wide monitoring and early warning systems

16. The Pitt Review (2008) recommended an improved system for joint monitoring of flood risk; the Government’s responses to the Pitt Review implemented the Met Office Environment Agency Joint Flood Forecasting Centre. This has led to a significant improvement in flood forecasting and early warning information being fed to agencies responsible for flood protection and response across the UK.

17. Flood forecasting systems are complex and can be constantly improved with more sophisticated models, running on faster supercomputers. It is important that the UK continues to invest in the latest technology and research capability to extend the skill and range of flood forecasts. Improved advance warning of floods will help authorities better prepare for impending floods.

18. Events in Germany, Switzerland and the Low Countries in July 2021 show the vulnerability of even the richest, most technologically advanced countries in the world to intense rainfall and flooding.

19. While inquiries in Belgium and Germany are ongoing to the causes of the disaster, this tragedy shows the importance of investment not only in adequate technical expertise and infrastructure to provide early warnings, but also a long-term, community-wide programme of adaptation and preparation for flooding. For critical national infrastructure, this has a multiplier effect; in Germany, failure to protect telecommunications infrastructure meant that planned emergency warnings were not received by many of those who were most at risk, for example.

Allocation of roles and responsibilities at national, devolved and local level

20. Despite the improvements in early flood warnings as outlined above, responsible authorities at local levels do not have the resources to undertake effective localised forecasting or risk management for infrastructure such as transport; to work with partners that run infrastructure. Many responsibilities lie with local councils, which are cash-starved and do not have adequate support from central government. Sending in the Army after an incident has occurred is too little, too late.

Opportunities presented by technological solutions (such as AI and digital twins)

21. The European Commission’s upcoming project, Destination Earth5, is a multi-billion-euro initiative designed to create a ‘digital twin’ of the Earth, which would help to improve forecasts and lead to more complex and accurate early warnings of hazards, such as floods and wildfires. This could be at several scales, including providing more skilful forecasts to improve day-to-day early warnings of climate hazards, such as floods, as well as to provide more information about risks over longer timescales.

22. The project involves the European Centre for Medium-Range Weather Forecasts (ECMWF), which is currently based in Reading and has committed to move to a new UK Government-provided HQ facility in Reading by 2026. However, the UK’s involvement in EU-funded projects is complicated by Brexit. AI and digital twin technology could be transformative to improve early warnings of climate risks but are likely to be extremely complex and expensive for one nation alone. To benefit fully from this emerging technology, the UK Government must ensure that the UK continues to maintain access to such complex, multi-national research projects.

7 January 2022


1 Kharaman et al (2021)

2 Bevacqua  et al (2019)

3Mehring et al (2021)

4 Brimicombe et al (2021)