People & the built environment

Increasing temperatures, rising sea-levels and modified rainfall patterns will change the climate-related risks to people and the built environment.

Climate change is expected to increase the frequency, severity and extent of flooding. According to research conducted to support the CCRA, at present an estimated 1.8 million people are living in areas of the UK at significant risk of river, surface water or coastal flooding. The population living in such areas is projected to rise to 2.6 million by the 2050s under a 2°C scenario and 3.3 million under a 4°C scenario, assuming low population growth and a continuation of current levels of adaptation.

Analysis conducted for the CCRA suggests that 0.5 to 1 metre of sea level rise could make some 200km of coastal flood defences in England highly vulnerable to failure in storm conditions. Sea level rise and increased wave action will make it increasingly difficult and costly to maintain current sea defence lines in some areas.

The number of heat-related deaths in the UK are projected to increase by around 250% by the 2050s (median estimate), due to climate change, population growth and ageing, from a current annual baseline of around 2,000 heat-related deaths per year.  There are also potential opportunities associated with higher temperatures. For example, outdoor activities may become more attractive, with perhaps an increase in active travel such as cycling and walking. Very little quantitative evidence exists that considers these benefits.

Cold is currently a significant public health problem, with between 35,800 and 49,700 cold-related deaths per year on average in the UK. Climate change is projected to reduce the health risks from cold, but the number of cold-related deaths is projected to decline only slightly due to the effects of a growing, ageing population increasing the number of vulnerable people at risk.

Health services will be vulnerable to an increase in the frequency and intensity of extreme weather events. The capacity of the system to cope with shocks is unknown but could decrease given pressures on the health service and local authorities.

Higher temperatures in the future may lead to the expansion of insect vectors for certain diseases. For example, Culex modestus has recently been found in south-east England and is a vector for West Nile virus. Higher temperatures in the future will also increase the suitability of the UK’s climate for invasive mosquito species. The risk of dengue and the Chikungunya virus remains low in the near term but may increase under a 4C scenario. The risk of malaria in the UK remains low.


Lead contributors: Sari Kovats, LSHTM, Dan Osborn, UCL

Contributing authors: Jon Ayres, University of Birmingham; Paul Bates, University of Bristol; Matthew Baylis, University of Liverpool; Sarah Bell, UCL; Andrew Church, University of Brighton; Sarah Curtis, University of Durham; Mike Davies, UCL; Mike Depledge, University of Exeter; Sotiris Vardoulakis, PHE/LSHTM; Nick Reynard, CEH; Jeremy Watson, UCL/BRE

Additional contributors: Anna Mavrogianni, UCL; Clive Shrubsole, UCL; Jonathon Taylor, UCL; Geoff Whitman, LSHTM

ASC contributors: Kathryn Humphrey, Dave Thompson and Daniel Johns

This chapter at a glance

Risks and opportunities

More action needed (research priority in Northern Ireland, Scotland & Wales)

The risk to health is likely to increase in the future as temperatures rise. There is some evidence that the risks of overheating in hospitals, care homes, schools and offices will increase in the future. There is more evidence for England than for the devolved administrations. Policies do not exist at present to adapt homes or other buildings to higher temperatures

Research priority (sustain current action - England, watching brief - Northern Ireland & Scotland)

The action underway in London to assess and manage risks of overheating on public transport should continue, together with similar action as needed elsewhere in the UK.

Watching brief

Leisure and other activities are likely to be taken up autonomously by people as the climate warms.

More action needed

Climate change is projected to reduce the health risks from cold, but the number of cold-related deaths is projected to decline only slightly due to the effects of an ageing population increasing the number of vulnerable people at risk. Further measures need to be taken in the next five years to tackle large numbers of cold homes and reduce cold effects on health, even with climate warming.

More action needed (research priority in Northern Ireland, Scotland & Wales)

Under the most optimistic flood defence investment scenario for England, the level of risk declines but remains high by mid-century, and future spending plans for the devolved administrations are unclear. Increases in flood risk cannot be avoided under a 4°C climate scenario even if the most ambitious adaptation pathway considered in this report were in place.

Research priority

Research is needed to better characterise the impacts from sea level rise on coastal communities, thresholds for viability, and what steps should be taken to engage and support affected communities.

Research priority

More research is needed to better determine the future level of risk and what further steps might be appropriate.

Research priority

Climate-related hazards damage historic structures and sites now, but there is a lack of information on the scale of current and future risks, including for historic urban green spaces and gardens as well as structures.

More action needed (research priority in Northern Ireland, Scotland & Wales)

There is some evidence of inconsistent planning for extreme weather across the UK. Surveys indicate that many Clinical Commissioning Groups, NHS providers, GPs and Local Authorities may not have appropriate plans in place.

Research priority

More research is needed to understand the influence of climate change on ground level ozone and other outdoor air pollutants (especially particulates), and how climate and other factors (e.g. individual behaviour) affect indoor air quality.

Research priority

Further research is needed to improve the monitoring and surveillance of vector species and related infectious disease, and to assess the extent to which current efforts are focussed on those infections that pose the greatest long-term risks.

Watching brief

Regulations in place to monitor and control food-related hazards should be kept under review.

Sustain current action

Current policies and mechanisms to assess and manage risks to water quality in the public water supply should continue to be implemented.

Sustain current action

Policies are in place to safeguard the continuity of public water supplies during droughts and from burst pipes in cold weather. These risks should be kept under review to make sure long-term risks continue to be managed appropriately.