The weather map is blazing red, and the presenter cheerfully announces that the heat is set to continue. However, summer heat is not good news for everyone. Prolonged heatwaves increase serious health risks and, in the worst cases, can be fatal. Project Manager Tiina Nygård calls for greater awareness of heat hazards.
When the mercury rises, the city becomes a furnace. Stone buildings, concrete structures and paved surfaces store heat and release it back into the urban air. This phenomenon is known as the urban heat island effect. The temperature difference between the city and the surrounding countryside can exceed 10°C.
Climate change is increasing the frequency and duration of heatwaves also in Finland. The number of sweltering days and sweaty nights is expected to increase.
‘Heatwaves already pose significant health risks and lead to higher mortality. They are particularly strenuous for the elderly, people with chronic conditions and young children, whose capacity to adapt to heat is most limited,’ explains Project Manager Tiina Nygård.
Nygård has a background as a researcher specialising in polar climates and is a Docent in Meteorology. She spent several years in Svalbard, an Arctic archipelago inhabited by polar bears, where global warming is happening faster than anywhere else in the world.
As project manager for the City of Lahti’s HELLE project, Nygård’s current work focuses on adapting to extreme weather phenomena in the Päijät-Häme region rather than glaciers. As part of the project, she examines how heatwaves affect wellbeing, daily life and residential environments, and how to prevent heat-related harm.
Nygård calls for greater awareness of heat hazards.
Most of us have experienced the milder health effects of heat – sleepless nights, tiredness, and reduced energy for work and leisure.
However, serious heat-related health risks are a regular cause of premature deaths, even in Finland.
‘Heat causes as many deaths as traffic, but the phenomenon is overlooked in public debate,’ Nygård laments.
Higher mortality is seen both in care homes and among older people living at home. The risk is highest for people living in urban heat islands, in older, poorly ventilated apartments where the indoor temperature cannot be brought down. Many older and chronically ill people spend a large part of the day indoors, even in summer.
‘During heatwaves, many people are left at the mercy of heat in their homes, and it is not always clear who should take responsibility for the situation’, Nygård notes gravely.
“Heatwaves already cause significant health impacts and increase mortality.”
According to national surveys in Finland, mortality among people aged over 65 increases by 21 per cent during heatwaves. Between 1999 and 2018, heatwaves led to an annual average of 108 premature deaths and 172 hospitalisations in Finland. The extreme heatwave of summer 2018 increased the number of premature deaths by almost 400. The cost of hospitalisations directly attributable to the heatwave was estimated at approximately EUR 2.85 million.
Nygård notes that there are around 200 road deaths each year in Finland. So, the death toll from a single hot summer can be twice as high as the annual toll from road accidents.
‘We invest hundreds of millions in traffic safety every year, but investment in preventing heat-related harm is nowhere near comparable. Like elsewhere, the adverse health effects of heat and the resulting costs are likely to be significant in Päijät-Häme, even though no precise regional estimates are available,’ Nygård says.
‘We need greater awareness of the serious impacts of heat. We need an understanding of these impacts and the will to address them. It’s a matter of life and death,’ Nygård remarks.
Heat isn’t an equal-opportunity risk: it hits hardest those least able to protect themselves. The risk is highest among people aged 65 and over. As people age, the body’s ability to regulate heat diminishes. In addition, some medications, such as antidepressants, beta-blockers and antihistamines can further impair the ability to regulate heat.
Heatwaves are also a significant risk for young children and pregnant women who are naturally more susceptible to heat.
Broadly speaking, a person’s health, functional ability and social circumstances affect how much time they spend at home and how well they can protect themselves from heat.
‘Supported housing and care home residents have virtually no say over where they live or the conditions in their housing environment,’ Nygård points out.
‘People with reduced mobility, chronic conditions or otherwise lowered functional ability may be exposed to heat at home if they are unable to leave the apartment for a cooler setting.’
According to Nygård, concrete action should be focused where the need is greatest: in the homes and care settings of older people and other at-risk groups.
‘Many older people are in need of technological cooling solutions. Other measures are simply not enough. Without proper cooling, indoor temperatures can reach levels that are harmful to health,’ she says.
With regard to home care clients, the problem is that no one seems to know who is responsible – or who covers the costs.
Action is also needed in day care centres. Shaded outdoor areas, heat-reflective surface materials and cool indoor spaces would ensure that children can play and be active even during heatwaves. Measures should be targeted at sites where heat causes the greatest problems.
Nygård stresses that preparedness planning is needed across the urban environment: yards and streets can be cooled through greenery and shade, and the city should provide places where people can seek refuge on the hottest days.
‘I’d like to see cooled public and private spaces around the city. Places that anyone can use when the heat becomes unbearable,’ Nygård says.
According to estimates, the number of heatwave-related deaths and hospitalisations in Finland may triple or even quadruple by 2050. By the end of the century, the figure could be six to seven times higher than it is today.
‘In that case, the number of heat-related deaths would match the number of road deaths in the 1970s and 1980s, when seat belts were not yet widely used in Finland.’
However, this trend is not inevitable. Heat-related harm can be significantly reduced through proactive adaptation measures – and that is the aim of Nygård’s HELLE project.
Facts in this article are based on the study coordinated by Tiina Nygård: Yleistyvät helteet Lahdessa ja Päijät-Hämeessä: Asukkaiden haavoittuvuustarkastelu (Increasing Heatwaves in Lahti and Päijät-Häme: Resident Vulnerability Investigation).