How can the built environment be adapted to changing UK summers?
The conclusions drawn within the Intergovernmental Panel on Climate Change’s (IPCC) AR6 Synthesis Report were explicit – human-induced climate change is “affecting many weather and climate extremes in every region across the globe.”
Published in March 2023, the report warned of the impact rising temperatures will continue to have on the global water cycle, leading to very wet and very dry weather patterns, climate events and seasons.
In cities, heatwaves and other hot extremes are predicted to increase, giving rise to compromised infrastructure, exacerbated air pollution events, disrupted services and economic loss.
The UK got a flavour of such devastation in 2022 following record-breaking temperature spikes, which engendered the nation’s fourth driest summer and prolonged drought conditions – a scenario that the National Drought Group has warned could be echoed in 2023.
It’s a bleak prognosis but one the UK’s built environment can and must be adapted to.
How is climate change impacting UK summers?
In the last decade alone, the average temperature of UK summers has risen by nearly 1°C.
By 2070, they are projected to be up to 6°C warmer and up to 60% drier if the highest emissions scenario unfolds.
Early suggestions of this future emerged last year when a record number of annual wildfires was documented, and 56 of the 109 longest-standing weather stations measured all-time temperature highs.
Brought on by the energy-trapping effect of greenhouse gas emissions, the heating of UK summers will profoundly impact our health and wellbeing – over 20,000 people died from heat-related causes across Europe last summer.
Productivity is also expected to decline, with hot weather putting workers at risk and impacting our ability to grow crops, the latter of which was evidenced by the toll drought conditions in East Anglia took on food production.
But it is not just the repercussions of standalone hot periods we need to worry about; according to the Climate Change Committee’s (CCC) March 2023 report, concurrent heatwaves and droughts, like those observed in 2022’s summer, can “significantly increase the individual hazard and overall risk.”
The report stipulates that when this happens, surface cooling from evapotranspiration is reduced and leads to unusually dry soils, which can cause localised rises in maximum temperatures.
This effect will subsequently boost both the risk of wildfires and the water demand, putting additional pressure on water supply infrastructure which is not optimised to cope.
Another problem arising from this scenario is the risk of flash flooding, which occurs when drought conditions leave the ground hard-baked and unable to absorb water runoff from heavy precipitation – another weather extreme the UK is expected to see more of in future.
The built environment must be adapted quickly to help mitigate the damage our ever-hotter summers will have.
How can the built environment be adapted to heating UK summers?
Modifying the built environment to deal with heatwaves and droughts in the UK is essential for human survival and our resilience following their occurrence.
An ongoing example is Transport for London (TFL)’s investment in sustainable drainage systems (SuDS) across four major schemes in their network.
Such implementation of green infrastructure will not only help control flood risks but can also store water for irrigation and provide cooling through evapotranspiration.
The latter advantage has been proven by research to reduce the urban heat island effect, a scenario describing an urban area which is considerably hotter than surrounding areas due to human activity.
In particular, this was an outcome reinforced by Gunwardena et al., who found that “greenspaces extend their microscale cooling effect greatest during conditions typical of high UHI intensity and heatwaves.”
The use of urban greening to control high temperatures was backed up by the IPCC report, which stated with high confidence that this would provide localised cooling.
But incorporating more green infrastructure like SUDS into new developments won’t be enough alone.
Other adaptation measures, such as installing large openings for ventilation or using heavy materials to absorb solar heat, will need to be considered – as will their ability to manage flood risk.
How can GeoSmart help property professionals to adapt to the built environment?
As a leading provider of sustainable drainage reports and detailed drainage designs, GeoSmart can help developers, architects and consultants to incorporate sustainable drainage systems into their developments to capture water runoff and help reduce the impact the building will have on urban temperatures.
To learn more about either of these services, speak to a specialist team member today.