Britain is burning. And Portugal, Spain, France, Italy and Belgium. When we think of climate disasters or extreme weather, we tend to think of hurricanes or wildfires. Heatwaves are typically reported as something milder or even something to enjoy, with stories featuring images of sprinklers and ice cream. The reality is that heatwaves are actually one of the most deadly forms of extreme weather. So what happens when temperatures rise to extreme levels?
The UK Met Office issued its first-ever “red heat warning” as the forecast warned of record-breaking temperatures exceeding 40°C, much earlier than scientists predicted. The UK should have a temperature climate with mild summers that seldom sees the 30s so this heat level is extreme and worrying. However, many media outlets reported the heatwave as “just summer” and climate denial Twitter was out in full force ridiculing warnings.
On the second day of extreme heat, with a new record set (40.2°C), a spate of wildfires broke out and Britons got a frightening taste of what it feels like to be on the frontlines of the climate crisis.
In mainland Europe, the summer heatwave was already reaching scorching highs, claiming more than 1,000 lives in Spain and Portugal. In Italy, 11 people were killed when a glacier in the Dolomites collapsed earlier this month.
And, it’s not just Europe. Record temperatures are being recorded in China and the US this summer too. This comes mere months after another brutal heatwave in South Asia where temperatures surpassed a sweltering 50°C. Heatwaves have killed more than 6,500 people in India since 2010 and climate change is causing them to be more intense and frequent.
A healthcare emergency
Extreme temperatures have a profound effect on humans. Both physically and mentally. In a heatwave, healthcare services can become overwhelmed with patients. The UK’s National Health Service declared a national emergency in anticipation of record-breaking temperatures last week. A recent study carried out in Turkey indicated that emergency rooms see a 10% rise in the ER when temperatures reach or exceed the normal range.
How heat affects our bodies
Sunburn, dehydration, heat exhaustion and heatstroke commonly occur in summer with varying degrees of severity. If not treated, they can even result in death.
Heat death is truly horrific. David Wallace-Wells, the author of “The Uninhabitable Earth”, explains, “Heat death can be just as painful and disorienting as hypothermia. First comes heat exhaustion, mostly a mark of dehydration; profuse sweating, nausea, and headaches. After a certain point, water won’t help, your core temperature rising as your body sends blood outward to the skin, hoping desperately to cool it down. The skin reddens and internal organs begin to fail. Eventually, you could stop sweating. The brain too stops working properly and sometimes after a period of agitation and combativeness, the episode is punctuated with a lethal heart attack.”
According to Wallace-Wells’ book, “the true red line for habitability is 35 degrees, beyond which humans simply begin dying from the heat.” With temperatures in excess of 35°C becoming more frequent, this is a scary prospect and one that we are underprepared to protect ourselves from.
The intent here is not to instil more fear and panic, there is certainly enough of that on the internet, but rather to underline the severity of heatwaves that the media repeatedly portrays as inconsequential.
Who is most at risk?
Around 12,000 people die from heat-related issues every year in the US. Approximately 80% of those are over the age of 60. One study stated that “Older bodies also hold more heat than younger ones when the temperature climbs. Glands don’t release as much sweat. The heart doesn’t circulate blood as well, so less heat is released from vessels in the skin. Systems from the cardiovascular to the immune struggle to compensate.”
Additionally, older adults are more likely to have chronic health conditions and take medications that cause heat intolerance. In fact, people of any age with disabilities and mental health conditions can experience heat-related complications. Some medications for mental health also increase sensitivity to heat, including SSRIs which are prescribed for depression and anxiety.
MS is a condition that affects the brain and spinal cord. In an article for the BBC, Dr Sarah Rawlings explained that in the heat symptoms worsen. They experience “balance, fatigue and changes to vision – which can be difficult to deal with.” In the same piece, Sabrina who has MS, says she struggled during the heatwave with painful muscle spasms. Roughly 130,000 people in the UK have MS, with 60% of those people reporting heat sensitivity.
Pregnant women are also at risk in the heat. There is a higher risk of complications – for every additional 1°C, the risk of stillbirths and premature birth is increased by around 5%.
Small babies and young children cannot regulate their temperature well and this can make them more vulnerable to heatstroke.
This is by no means an exhaustive list. It is not an overstatement to say that extreme heat is dangerous for huge percentages of the population. And when it’s especially hot, it’s harmful for everyone – even those that are otherwise healthy and low risk.
When home doesn’t provide protection
Other groups are vulnerable because of their living conditions. Many people live in homes that are difficult to keep cool, like south-facing or top flats and homes without adequate insulation (which helps keep in heat during winter and stay cool in summer). Even when people have air conditioning or fans, the price of the energy needed to run them can be prohibitive.
Some city neighbourhoods, know as “urban heat islands” can be even hotter due to a lack of shade from trees and an abundance of asphalt and concrete, which hold more heat.
Homeless people, especially those who are sleeping rough, are exposed to the elements all day and night. We often think about homeless people when it’s cold or raining outside but tend to forget that summer comes with its own risks. Imagine having no choice but to be outside on the hottest day on record. No air conditioning, no fan, no fridge. Vulnerable to sunburn and heatstroke, stressed and uncomfortable, desperately seeking shade from the ferocious sun.
Refugees in camps are forced to bear similarly lethal situations. In cramped conditions, often without access to clean running water, with frequent power outages and rudimentary healthcare. The same can be said of prisons, where prisons are not designed for extreme weather conditions.
No one should have to live in conditions that make them more vulnerable to the effects of the sun but millions do and with heat waves becoming more frequent and more extreme, we are facing a humanitarian crisis.
When work doesn’t provide protection
Of course, this is also a huge issue for workers. In particular, workers in the agricultural sector. Wallace-Wells gives the example of El Salvador where “as much as one-fifth of the population – including over a quarter of men – has chronic kidney disease, the presumed result of dehydration from working the fields”.
Some countries have limits on the maximum temperature that workers can work in but many, including the UK, do not. In the US, where many agricultural workers are undocumented and are not unionised, there is little choice but to take your chances and go to work.
Earlier this year, at the height of the heatwave in South Asia, Reuters reported that women, including those that are pregnant, were left with no other options but to work out in the field, despite the lethal temperatures of over 50°C.
How heat affects our minds, and behaviour
As if the physical risks weren’t enough, hot weather also has a negative impact on our mind. Researchers have observed links between heatwaves and increased symptoms in people with mental health conditions like depression and anxiety. Scientists have also found links to suicide and suicide attempts. For around every 1°C increase in the monthly average temperature, deaths related to mental health conditions go up by roughly 2.2%.
Violence
As noted in this BBC article, “People have suspected that warm weather can alter our behaviour for centuries. The idea is embedded into our very language – we talk of tempers “flaring”, “incandescent” rage, getting “hot under the collar.”
Evidence reveals a strong correlation between higher temperatures and an increase in violent crimes. Although there isn’t one conclusive reason for the link with violence, scientists have several compelling theories. One of the main factors for this is that high temperatures lead to irritability and aggression. Hot weather can make us uncomfortable.
Research has also found that heat stress can impair cognitive function. In 2017, scientists in Finland discovered that temperature correlated with the amount of serotonin in the brain. This suggests that heat changes our serotonin levels, which can result in aggression. Another hypothesis is that hot weather increases testosterone levels, which also makes us more aggressive.
The US experienced record-breaking temperatures back in 1988. During the heatwave, it also witnessed an unexpected spike in violence. An alarming 1.56 million reported instances of murder, rape, armed robbery and assault. Now, the US is in the midst of another scorching heatwave with cities across the country battling to cope with temperatures up to 110°F (43°C). Will this have an impact on crime?
When the forecast shows a heatwave is on the way, domestic violence organisations warn of the potential for an increase in abuse. “When the weather gets warmer, we have an increase in [domestic violence] clients and an increase of higher lethality situations,” says Brittany Rees of the Spouse Abuse, Sexual Assault Clinic in Hastings, Nebraska.
In addition to biological factors, when temperatures are very high there can tend to be a number of other stressors like transport delays and power outages.
The bigger picture
Of course, heatwaves don’t just affect humans – they affect every living being in nature. Plants and animals have evolved to live in an environment, which includes acclimation to the weather. During a heatwave, temperatures rise above what is normal and animals are affected in similar ways to humans. In India, exhausted birds were literally falling out of the sky as temperatures soared.
Crop failures are also a common consequence of heatwave. Often, this is due to heat-related drought. Like humans, without enough water, most crops cannot survive for long.
Additionally, farmers are increasingly seeing that atypical temperatures in Spring can kill pollen, even when there is sufficient water, disrupting the fertilisation of crops. This happens at around 90°F (32°C).
At 1.5°C warming, about 14% of the world’s population will experience excruciating heat waves at least once every five years. At 2°C, just a fraction hotter, it will be 37% of the population.
Is there any good news?
If this all sounds rather bleak and terrifying, well, that’s because it is. We are in the thick of a global climate emergency and the impact is devastating. While heatwaves have been intensifying in the Global South for years, they are now engulfing every part of the world. It shouldn’t have to take experiencing the climate emergency on your own doorstep to motivate people into action, but this is where we are. Now that it has well and truly arrived for even the most privileged among us, we are likely to see more people spurred into action.
There are things that we can do, no matter where we are or what our circumstances are. It’s clear from the examples above that global heating is an issue of justice. For women, for disabled people, for people of colour, for people living in poverty, for undocumented workers, for refugees. Advocating for equality and human rights is as much a part of fighting climate change as reducing emissions or protecting nature. Ensuring people are safe and protected is part of creating climate solutions. Investing in our healthcare and emergency services is climate action.