Does climate change increase mortality? Heatwaves, drought, flooding, disease and conflict might all play a role.
Extreme temperatures lead to increased mortality risk — a risk that is aggravated by climate change, especially at the height of summer. Other factors such as an ageing population, urbanisation and levels of local and national preparedness can also play their part.
Every European heatwave that has been analysed in recent years has been found to be made much more likely and more intense due to human-induced climate change.
The extremely high temperatures of summer 2003 that may have caused up to 70,000 excess deaths across Europe – as well as the July 2019 heatwave – were so extreme that the observed magnitudes would have been extremely unlikely without climate change.
This trend is likely to increase in the future, and it is estimated that a typical 2080 heatwave will see mortality rates three times higher than in recent times.
The effects of these extreme temperatures are far-reaching: from delayed trains and sleepless nights, to deaths from drowning and an increased mortality risk for the elderly, babies and vulnerable populations. Other health issues, such as dehydration, are more prevalent in extreme temperature situations.
Temperatures tend to be a few degrees higher in towns and cities compared with rural areas, leading to 'urban heat islands'; urban areas tend to have more heat absorbing surfaces than rural areas. This effect can be partly offset with measures like using reflective 'cool' roofs, where dark roofs are replaced with a more reflective grey or white coating.
Heatwaves are just one deadly element of climate change. More frequent droughts are brought on as some regions become hotter and drier. Flash flooding also increases due to extreme rainfall events and patterns of infectious diseases and air pollution change as weather conditions change. All these can lead to food and water insecurity, which in turn leads to forced migration and local and regional conflicts.