Switzerland, UK and Norway "dangerously unprepared" to keep people cool if global 1.5ºC target is missed

• Switzerland, UK and Norway will see the world’s most dramatic relative increase in uncomfortably hot days, but are under prepared
• Central Africa will see the most extreme temperatures overall
• Striving to remain below 1.5ºC warming is essential to mitigating these impacts
• The research aims to inform COP28 where the UN and host nation UAE hope to develop a “Global Cooling Pledge.”

Switzerland, UK and Norway will see the world’s most dramatic relative increase in days that require cooling interventions – such as window shutters, ventilation, fans, or air conditioning – if the world overshoots 1.5 ºC of warming, according to new University of Oxford research.

Switzerland and the UK will see a 30% increase in days with uncomfortably hot temperatures if the world misses the 1.5ºC target and heats to 2ºC, while Norway will see an increase of 28%. The researchers stress that this is a conservative estimate and does not consider extreme events like heatwaves, which would come on top of this average increase.

Eight of the 10 countries facing the greatest relative increase in uncomfortably hot days are expected to be in Northern Europe, with Canada and New Zealand completing the list. For countries with a population of over 5 million, Switzerland and the UK top the list, followed by Norway. But when the authors took countries with populations of two million and over into account, Ireland came top.

The researchers believe these countries are dangerously underprepared for this change. “Right now, for example, sustainable cooling barely has a mention in the UK’s net zero strategy,” says co-author Dr Radhika Khosla, Associate Professor at the Smith School of Enterprise and the Environment nd leader of the Oxford Martin Programme on the Future of Cooling.

Dr Khosla continues:

Without adequate interventions to promote sustainable cooling we are likely to see a sharp increase in the use of energy guzzling systems like air conditioning, which could further increase emissions and lock us into a vicious cycle of burning fossil fuels to make us feel cooler while making the world outside hotter.

Co-lead author Dr Jesus Lizana explains, “If we adapt the built environment in which we live, we won’t need to increase air conditioning. But right now, in countries like the UK, our buildings act like greenhouses - no external protection from the sun in buildings, windows locked, no natural ventilation and no ceiling fans. Our buildings are exclusively prepared for the cold seasons.”

Co-lead author Dr Nicole Miranda adds, “Northern European countries will require large-scale adaptation to heat resilience quicker than other countries. The UK saw massive amounts of disruption in the record-breaking heatwaves of 2022. Extreme heat can lead to dehydration, heat exhaustion, and even death, especially in vulnerable populations. It’s a health and economic imperative that we prepare for more hot days.”

The top ten countries that will experience the highest needs for cooling overall in a 2.0ºC scenario are all in Africa, with central Africa most affected. “These conditions will pose further stress to the continent's socio-economic development and energy networks… issues that require much additional research given the limited studies of this rising threat in the African context,” says Dr Khosla. “It is also a clear indication that Africa is bearing the brunt of a problem they did not create, which should further strengthen calls for climate justice and equity.”

For their analysis, the authors used the concept of “cooling degree days,” a method widely employed in research and weather forecasting to ascertain whether cooling would be needed on a particular day to keep populations comfortable. They modelled the world in 60kmgrids every six hours to produce the temperature averages in the study, a process that makes the results some of the most reliable globally.

“Cooling demand can no longer be a blind spot in sustainability debates,” concludes Dr Khosla. “By 2050 the energy demand for cooling could be equal to all the electricity generated in 2016 by the US, EU and Japan combined. We have to focus now on ways to keep people cool in a sustainable way.”