A new report from the Government’s independent Adviser on climate change is warning that flooding is the greatest direct climate change-related risk to UK infrastructure, while severe water supply deficits are set to deepen and extend across the UK by the 2050s.

The UK Climate Change Risk Assessment 2017 report by the Adaptation Sub-Committee (ASC) of the Climate Change Committee( CCC) published today, says the impacts of climate change are already being felt in the UK, and urgent action is required to address climate-related risks.

The greatest direct climate change-related threats for the UK are large increases in flood risk and exposure to high temperatures and heatwaves, shortages in water, substantial risks to UK wildlife and natural ecosystems, risks to domestic and international food production and trade, and from new and emerging pests and diseases.

Introducing the report, Lord Krebs, Chairman of the Adaptation Sub-Committee of the Committee on Climate Change, said:

“The impacts of climate change are becoming ever clearer, both in the United Kingdom and around the world. We must take action now to prepare for the further, inevitable changes we can expect. Our independent assessment today, supported by the work of hundreds of scientists and other experts, identifies the most urgent climate change risks and opportunities which need to be addressed. Delaying or failing to take appropriate steps will increase the costs and risks for all UK nations arising from the changing climate.”

The report says that a warmer atmosphere can hold more moisture, leading to heavier rainfall and more frequent flooding, including outside of recognised flood risk areas, while projected sea level rise of 50-100 centimetres by 2100 will exacerbate flood risks. Dry periods, when combined with higher temperatures, are likely to result in more severe and prolonged droughts.

Changes to the UK climate are likely to include periods of too much or too little water, increasing average and extreme temperatures, and sea level rise. The report concludes that the most urgent risks for the UK resulting from these changes are:

• Flooding and coastal change risks to communities, businesses and infrastructure.
• Risks to health, wellbeing and productivity from high temperatures
• Risk of shortages in the public water supply, and water for agriculture, energy generation and industry, with impacts on freshwater ecology.
• Risks to natural capital, including terrestrial, coastal, marine and freshwater ecosystems, soils and biodiversity.
• Risks to domestic and international food production and trade.
• Risks of new and emerging pests and diseases, and invasive non-native species, affecting people, plants and animals.

Risks of cascading failures arising from interdependent infrastructure networks

On cross-cutting risks, the ASC is also warning that the true magnitude of risks and opportunities may be underestimated because each tends to be considered in isolation but in practice will act in combination - the impacts of climate change could be amplified by interdependencies between infrastructure sectors. The Report says actions to address risks need to be co-ordinated amongst the various responsible bodies to be effective. However, current governance arrangements mean that responsibilities for assessing and managing risks from interdependencies are unclear.

The ASC is calling for more action to enhance arrangements for information sharing in order to improve understanding of critical risks of cascading failures arising from interdependent infrastructure networks.

Flooding is most significant climate change risk to UK infrastructure

Increasing frequency and severity of flooding represents the most significant climate change risk to UK infrastructure, according to the report. All infrastructure sectors are already exposed to multiple sources of flooding, and the number of assets exposed to significant levels of flood risk could double by the 2080s with projected changes in the UK climate.

Coastal infrastructure, particularly ports, is at risk from rising sea levels and a corresponding increase in the height of storm surges. Infrastructure networks near rivers will be exposed to higher flows and erosion of bridge foundations. The collapse of ageing bridges in recent flood events highlights the potential for knock-on impacts, as bridges often carry gas pipelines as well as electricity, telephone and data cables.

The report is calling for action to deliver a wider uptake of natural flood management in high-risk catchments and the implementation of catchment-scale planning for flood risk management. It also recommends reviewing the potential for adverse flood risk outcomes from land management subsidies.

Impacts of flooding and coastal change in UK already significant & expected to increase

The report says the impacts of flooding and coastal change in the UK are already significant and expected to increase as a result of climate change. At the national level, more ambitious approaches to adaptation could offset increases in expected annual flood damage if global warming is limited to 2°C.

However, the ASC says that within this national projection local impacts will vary considerably and that improving protection for some communities will be possible whilst others will face the prospect of significantly increased risks. This will affect property values, business revenues and in extreme cases the viability of communities. Warming of 4°C or more implies inevitable increases in flood risk across all UK regions even in the most ambitious adaptation scenarios considered.
Commenting on the magnitude of flooding and coastal change risks to communities, businesses and infrastructure, the report says the ASC has high confidence that this is high magnitude both now and in the future and that more action needed.

Water demand set to exceed available supply in large areas of England

On water availability, the report says that climate change is projected to reduce the amount of water in the environment that can be sustainably withdrawn whilst increasing the demand for irrigation during the driest months. Changing rainfall patterns and increased evapo-transpiration, coupled with population growth, are projected to lead to water demand exceeding the available supply across large areas of England and some other parts of the UK by the 2050s in some scenarios.Widespread deficits are projected by the 2080s in most climate and population scenarios.

At the same time, the growing population will create additional demands on already stretched resources in some parts of the country.The report states:

“Even low population growth and modest climate change scenarios suggest severe water supply deficits, and with high population growth and more severe climate change these deficits deepen and by the 2050s extend across the UK.”

“Whilst there is significant action already underway, there is an urgent need for longer-term water resource planning to assess the scale of risks and consider strategic options, more co-ordinated action to ensure resilient supplies especially in times of drought, and further steps to achieve the ambitious reductions in water demand and leakage that are likely to be required.”

“Otherwise there could be increasingly difficult trade-offs between the needs of industry, farming and the public water supply, and the ecological status of rivers, lakes, estuaries, and groundwater.”

The Committee says increasing investment and adaptation by water companies will be needed to manage this risk, starting with the full implementation of current water resource management plans (WRMPs) between now and the 2030s.

The report is suggesting that there would also be merit in WRMPs having a longer than 25-year time horizon, to make sure water companies take full account of the uncertainty in future projections through to the middle of the century and beyond. In some cases early steps may need to be taken to assess and retain long-term water supply options.

Urgent action needed to address key risks

The ASC is calling for more action to address risks in key areas, including:

• Risks to infrastructure services from river, surface water and groundwater flooding - More action is needed to manage increasing risk to existing assets and networks and ensure increased risk is accounted for in design and location of new infrastructure.
• Risks to infrastructure services from coastal flooding and erosion - More action is needed to manage increasing risk to existing networks (including flood and coastal erosion risk management infrastructure), from sea-level rise and increased rate of erosion.
• Risks of sewer flooding due to heavy rainfall - More action is needed to deliver sustainable drainage systems, upgrade sewers
• where appropriate, and tackle drivers of increasing surface runoff (e.g.impermeable surfacing in urban areas).
• Risks to bridges and pipelines from high river flows and bank erosion - More research is needed on implications of projected changes in river flows on future risk of scour/erosion.
• Risks to public water supplies from drought and low river flows - New policies and stronger co-ordinated, cross-sector effort are needed to deliver more ambitious reductions in water consumption and establish strategic planning of new water-supply infrastructure. More action is also needed to put in place reforms of the water abstraction licencing regime.

The report is also flagging up risks to electricity generation from drought and low river flows, suggesting that action should be taken to ensure the appropriate siting of new infrastructure, including the use of suitable cooling technologies. On risks to offshore infrastructure from storms and high waves, more research is needed to assess climate risks to existing and planned off-shore renewable energy infrastructure.

EU Referendum could affect magnitude of risks and opportunities if EU-derived legislation, policy and funding changes

On the implications of the EU Referendum, the report says the recent vote in favour of leaving the European Union does not change the overall findings of the risk assessment. Commenting on the implications of the EU referendum, in the Committee’s view the impact of the recent vote to leave the European Union does not change the overall conclusions of the risk assessment. However, the report says some individual risks may change if EU-derived policies and legislation are withdrawn and not replaced by equivalent or better UK measures.

The magnitude of individual climate change risks and opportunities could be affected if legislation, policy and funding derived from the EU, relevant to climate change adaptation, are changed. Important areas include the Common Agricultural and Fisheries Policies, the Water Framework, Bathing Water, Birds, Habitats, Floods, Urban Waste Water Treatment and Solvency II Directives, and the European Structural Investment Fund. 

Lord Krebs commented:

“The next report will also take account of the recent vote to leave the European Union. EU-derived legislation has served to raise environmental and other standards in the UK over recent decades. If the vote to leave the EU changes the UK’s legal framework it will be important for new laws and policies to be introduced that preserve the long-term outcomes that need to be achieved, to avoid the risks from climate change increasing. The ASC’s next report will consider whether the relevant domestic policies and proposals coming forward are commensurate with the risks from climate change.”

The ASC will assess the implications of the EU referendum and the Government’s response to the result in its next statutory report to Parliament on the UK National Adaptation Programme, due to be published in June 2017.

Next steps

The UK Government will now consider the findings of the ASC report and present their formal Climate Change Risk Assessment of the climate change risks and opportunities for the UK to Parliament in early 2017. The UK and devolved governments are then each expected to update their national adaptation programmes to address the risks identified, beginning with the second UK National Adaptation Programme, expected in the summer of 2018.

Looking to the future, the report says plans are underway to enhance the evidence base in advance of the third Climate Change Risk Assessment due to report in 2022. Key to this will be the production of updated UK climate projections in 2018. The Met Office is leading the work to update the UK climate projections - however the report warns that the new projections are being developed “within significant resource
constraints and the number of emission scenarios and model runs are likely to be limited.”

Click here to download UK Climate Change Risk Assessment 2017 Synthesis report: priorities for the next five years

Click here to watch Lord Krebs discuss the key findings of the ASC report