In this ‘era of global boiling’, heat has become a health issue for the world

As extreme temperatures grow more frequent, affecting food supplies, threatening health and taking lives, systems-wide approaches are needed to mitigate the harm
Governments, businesses, universities and communities must work with leaders in public health to address this growing emergency

Julie Davies

Published: 3:00am, 6 Aug 2023

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Last week, the World Meteorological Organisation said it was “extremely likely” that July would be the world’s hottest month on record. In response, UN Secretary General Antonio Guterres declared that “the era of global boiling has arrived”.

At the same time, the El Niño weather phenomenon is aggravating climate warming and scientists predict that heat records will again be shattered next year. El Niño refers to the warming of sea surface temperatures that occurs every few years, typically concentrated in the central-east equatorial Pacific.

This year so far has seen extreme heat – and weather – around the world. In northwestern China’s Xinjiang, temperatures hit a high of 52.2 degrees Celsius in the township of Sanbao on July 16. Days later, Beijing experienced its 27th consecutive day hotter than 35 degrees.

In April, Malaysia suspended outdoor activities in school and the wearing of school uniforms because of the heat. In Singapore, May was the warmest month on record, with an average temperature of 29.5 degrees, while New Delhi recorded a blistering 49 degrees in May – and then its wettest day in July in over 40 years.

In Europe, Spain and Portugal suffered from excess heat-related deaths and disruptions to agriculture because of heatwaves. In June, red and orange heatwave alerts were issued in most of France.

In July, Rome reached a historically high temperature of 41.8 degrees while Sardinia and Sicily experienced intense heatwaves. Warnings of a third heatwave of 46 degrees were issued in Greece at the end of the month after wildfires broke out on Rhodes and Corfu. In North America, record-breaking daily maximum temperatures of over 43 degrees were reported in Phoenix, Arizona.

Firefighters and paramedics wheel a resident to an ambulance from a bus stop during a heatwave in Phoenix, Arizona, US, on July 20. Photo: Bloomberg

Fortunately, the air conditioning kept going in Phoenix. If it hadn’t, heatwaves can be, as Jeff Goodell warns in his new book The Heat Will Kill You First, predatory events that tend to kill the most vulnerable. It is estimated that over five million people could die each year globally as a result of excessive heat or cold.

The BBC series Life at 50 degrees vividly illustrated the under-reported heat-related deaths and distress. Increased risks arising from extreme temperatures during El Niño include higher rates of mosquito-transmitted diseases and civil unrest.

When our bodies get too hot, we sweat to cool down. But, in a deadly heatwave, sweating is no longer enough to cool us down to the core temperature of 37.5 degrees. Without respite, heat exhaustion sets in with headaches, dizziness, cramps, a fast pulse and one can feel sick and thirsty. Heatstroke can occur, which is life-threatening when the body temperature reaches or exceeds 40 degrees.

Businesses are also vulnerable to the financial risks resulting from extreme heat, such as production losses. There are serious implications for food supply and affordability, supply chains, jobs and the economy amid a cost of living crisis.

02:32

July 2023 expected to be world’s hottest month in recorded history

Many expect El Niño to further push up commodity prices and inflation. Heat stress can make it impossible for outdoor work, affect the growth and productivity of agriculture and farm animals, impact water and food security, and hinder transport and factory operations.

Drought conditions have stunted maize crops in northern China’s Chengde, while floods have damaged wheat in central Henan province. China’s drought last year was already its harshest in 60 years with temperatures above 40 degrees – affecting the well-being of hundreds of millions of people.

Guterres argues that “leaders must lead”. In Hong Kong, for instance, policymakers, urban planners, academics and NGOs are collaborating on public education, the training of health professionals and emergency preparations.

Solutions can include spending on water supplies and irrigation systems, drought-resistant seeds, producing more food indoors and moving livestock into cooled sheds.

02:26

Record temperatures expected globally in 2023 as El Nino weather pattern returns

Employment regulations must be implemented to protect workers from hyperthermia. The International Federation of Red Cross and Red Crescent Societies, the world’s largest humanitarian network, has created a heatwave guide for cities.

Local politicians can enforce cooling plans and appoint chief heat officers to be responsible for unifying city governments’ responses to extreme heat, accelerating heat protection efforts and initiating work to reduce the risks and impact of extreme heat. Excessive heat clearly affects the most marginalised. For the sake of society and their own sustainability, businesses must cut their carbon emissions.

On a positive note, The Lancet noted last year that employment in China’s renewable sector continued to grow, accounting for 40 per cent of the global share. However, China still needs to accelerate its shift towards a carbon-neutral economy, encourage a greater inclusion of clinically vulnerable people in its health and climate change policies, and improve collaboration between institutions.

28:58

China, climate change and El Nino: an emerging food, water and power crisis

As we look towards the UN’s COP28 climate change conference in Dubai this November and December, we will hear more about what it calls the drive for a “global transformation towards a low-emission and climate-resilient world” and “ambitious climate action”.

Systems-wide approaches are needed to mitigate the climate harm to health globally – and to reduce the negative effect of the environment on the health sector. The impact of climate change on health requires governments, businesses, universities and communities to share information transparently with leaders in public health to address this growing emergency.

Whether in climate change, environmental, social and corporate governance (ESG) and other investments and interventions, the negative impact on health must be reduced, and we should also adapt our behaviour in light of this climate and public health crisis.

It is going to take a coordinated, long-term effort to find a way out of the environmental problems mankind has created – we must all work together to find solutions.

Professor Julie Davies is director of the MBA Health Programme at the Global Business School for Health, University College London