Tracing fatalities caused by heatwaves as the silent nemesis of climate science
In a groundbreaking move, scientists have estimated the number of deaths attributable to climate change in a recent heatwave that swept through western Europe. The study, published just a week after temperatures peaked, suggests that 2,300 people may have perished across a dozen major cities due to the extreme heat.
The research, led by scientist Friederike Otto, is the first of its kind to link heatwave deaths to climate change so soon after the event. According to Otto, the urgency in publishing the study was crucial to get the message out about heatwaves and keeping people safe.
The heatwave in question was during western Europe's hottest June on record, with temperatures soaring to 46C in Spain and Portugal. The authors of the study believe the true toll of the heatwave was likely much higher than the estimated 2,300 deaths. Heat can claim tens of thousands of lives during European summers.
Otto and her team's estimate indicates that 65% of the deaths, around 1,500 people, would not have occurred in a world without global warming. This brings the impact of climate change "closer to home" and makes it more real and human, according to Otto.
The study highlights the urgent need to prioritize vulnerable populations, integrate scientific data into urban design, and implement both immediate relief measures and long-term infrastructural changes.
Current best practices for cities to prepare for and mitigate heatwave-related deaths involve a multifaceted and evidence-based approach. This includes urban micro-climate interventions, urban planning for heat resilience, harnessing wind and natural ventilation, data-driven planning and innovation, and long-term, systemic heat strategies.
Urban Micro-Climate Interventions involve implementing localized cooling solutions such as shaded bus stops, community gardens, water stations, and increased vegetation to reduce urban heat islands. For instance, New Jersey’s $5 million grant program funds community-led projects specifically targeting vulnerable populations, illustrating the effectiveness of bottom-up, evidence-driven initiatives.
Urban Planning for Heat Resilience can be achieved by incorporating heat-adaptive building codes requiring green roofs or reflective building surfaces. Cities like Antwerp mandate such measures, while "sponge city" concepts that manage flooding while mitigating heat through water retention and permeable surfaces are gaining traction in German cities.
Harnessing Wind and Natural Ventilation can be achieved by designing urban growth to preserve wind corridors and green spaces. Stuttgart’s decades-long practice has become a model, now influencing other global cities to improve urban ventilation and reduce heat accumulation.
Data-Driven Planning and Innovation are crucial, with advanced urban climate data, modeling, and integration of future climate projections into building simulations enabling safer and more temperature-resilient design for homes, schools, and workplaces. Hackathons and programs like the World Bank’s City Resilience Program mobilize low-income cities to apply such innovations.
Long-Term, Systemic Heat Strategies vs. Emergency Responses are emphasized, with experts urging a move beyond piecemeal or emergency-only responses towards coordinated, strategic planning that links small interventions into comprehensive heat action plans to sustain benefits over time.
Cross-Sector Collaboration is also key, with collaborative efforts across sectors (public health, urban planning, community organizations) and targeted interventions showing significant improvements in managing heatwave risks, reducing heat exposure, and promoting adaptive measures.
Tailoring this approach to local conditions could help cities better prepare for heatwaves, according to Abhiyant Tiwari, a health and climate expert. However, heat deaths are widely undercounted, so more such studies on heatwave deaths and climate change are likely to follow, according to Tiwari.
Otto also emphasized that there is a lot that people and communities can do to save lives during heatwaves. Since the study, Turkiye, Greece, and Bulgaria have suffered fresh heatwaves and deadly wildfires, underscoring the need for immediate action.
[1] New Jersey’s $5 million grant program for community-led projects: https://www.nj.gov/environment/greenacres/news/2022/06/23/governor-murphy-announces-5-million-in-funding-for-community-led-projects-to-address-extreme-heat-resilience.shtml [2] Sponge city concepts in German cities: https://www.dw.com/en/german-cities-to-become-sponge-cities-to-absorb-rainwater/a-58724344 [3] World Bank’s City Resilience Program: https://www.worldbank.org/en/topic/urbanization/brief/city-resilience-program [4] Stuttgart’s urban ventilation practices: https://www.theguardian.com/cities/2017/nov/30/stuttgart-germany-air-pollution-green-roofs-urban-forests [5] Cross-sector collaboration for heatwave management: https://www.sciencedirect.com/science/article/pii/S2214629618301149
- The recent study linking deaths attributable to climate change in the European heatwave to the rise in global warming emphasizes the importance of incorporating scientific data into urban planning, especially for heat-resilience.
- Urgent and evidence-based approaches are needed to protect vulnerable populations from the impact of extreme heat, such as urban micro-climate interventions, green roofs, reflective building surfaces, and preserving wind corridors in urban growth.
- Adopting cross-sector collaborations and targeted interventions can help cities better prepare for and manage heatwave risks, reducing heat exposure and promoting adaptive measures.
- Heat deaths are widely undercounted, so more studies on heatwaves, climate change, and their combined effects, like the one led by scientist Friederike Otto, are crucial to get the message out and save lives.
