CNN
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Human-caused climate change has already made heat waves around the world more frequent and intense.
Scientists studying the role of global warming on the climate say that every heat wave today bears the fingerprints of the climate crisis.
Climate change, driven primarily by humans burning fossil fuels, is making global extreme weather worse overall, but much of that change is related to heat.
In the United States, heat kills more Americans than any other climate-related disaster, and it will only continue to worsen as the world warms from burning fossil fuels.
Here’s what happens to your body in extreme heat, what you need to watch out for and how to stay safe.
What happens to your body
Normally, your body is used to a certain range of temperatures, usually between 97 to 99 degrees Fahrenheit. When your brain senses a change — whether it’s lower or higher than that — it tries to help your body cool down or warm up, according to Dr. Judith Linden, executive vice chair of the department of emergency medicine at Boston Medical Center. and a professor in the department of emergency medicine at Boston University School of Medicine.
“There are a number of different ways that (the brain) tries to cool the body. One way, the most common way that we think of, is that you sweat,” Linden said. “The pores open, the body sweats and the sweat evaporates, which refreshes the body.”
The second way that your body cools is by dilating vessels and increasing the heart rate, which helps to bring heat and blood to the surface of your body and helps to release excess heat.
When you are exposed to high temperatures, it becomes more difficult for your body to try to keep cool. And if your environment is hot and humid, sweat doesn’t evaporate as easily—which pushes your body temperature even higher, according to Mayo Clinic.
“The higher the humidity, the lower the temperature you need for extreme heat,” Linden said.
High body temperature can lead to damage to the brain and other vital organs, the CDC he says They can also lead to many heat-related illnesses.
Mild heat-related illnesses, including heat cramps, are more common, Linden said. Heat cramps can develop in people who sweat a lot, even during exercise. Excessive sweating uses up all the salt and moisture in the body and can lead to muscle pains or spasms, usually in the abdomen, arms or legs, depending the CDC.
A heat rashit can also develop. It’s a skin irritation caused by too much sweating in hot, humid weather, and it’s more common in children, the CDC says. It is usually a red cluster of pimples or blisters, and tends to be in places including the neck, upper chest or in the crook of the elbow.
When your body begins to exceed its ability to cool down, you can develop what is known as heat exhaustion.
“In this case, you will see excessive sweating because your body will really try to keep the extra heat. You will feel dizzy, you may feel dizzy, often people have nausea, headaches and their skin often looks pale and moist and his pulse is often fast,” Linden said.
“This is the body’s last attempt to cool down before it really enters a point of no return.”
A heat strokeit is the most serious disease related to heat, and if it is not treated, it can lead to death.
“That’s where your body temperature goes above 104 to 105 degrees or more, and that’s where your mechanisms start to fail,” Linden said.
Warning signs can include extremely high body temperatures, red, dry skin, a rapid pulse, headache, dizziness, nausea or loss of consciousness, according to the CDC.
The hallmark of heat stroke is confusion and agitation, Linden said.
“So when someone is in heat and becomes confused and agitated, that’s heatstroke until proven otherwise and you need to call 911 for that or get help immediately and get the person out of the heat.”
The elderly, people with chronic medical conditions and even children are at greater risk for severe heat-related illnesses.
The elderly and people with chronic medical conditions may be less likely to sense and respond to temperature changes and may take medications that worsen the effects of heat, the CDC he said.
“Also very young (people), because they’re less likely to recognize heat-related illnesses and they’re less likely to get out of the heat if they start to feel overheated,” Linden said.
Student-athletes and pets are also at greater risk, he added.
“During this time, you should never, ever, ever leave a child or pet in the car for even a minute,” Linden added.
When your community experiences extreme heat, there are several things you can do to keep yourself and others safe.
First, keep an eye out for symptoms of heat exhaustion or other illnesses. “If someone starts feeling light-headed, dizzy, nauseous or has a headache, it’s time to act immediately,” Linden said. “That means getting them out of the heat and into a cool environment.”
Putting water on someone who may have symptoms and giving them fluids can help cool them down. If someone starts to lose consciousness or has nausea or vomiting, call 911.
“If you see someone with any kind of confusion, that’s an immediate red flag,” Linden added.
When it’s hot outside, try to avoid outdoor activities – especially between the hours of 11 am and 3 pm, according to Linden. If you have to go out, wear light colored clothes, cover your head and drink plenty of fluids.
Don’t wait until you’re thirsty to drink water – because that can be a sign of dehydration. Linden recommends drinking at least one glass of water — or more — an hour.
“If you start feeling light-headed, dizzy, sweaty, fast pulse, get out of the heat immediately,” said Linden.
Try to find air conditioning, or places in your area where you can go to stay cool, depending on Ready.gov. Even spending a few hours at a mall or public library can help.
When you’re indoors, fans can help, but don’t rely on them as your only way to cool down—while they may be more comfortable, they won’t help prevent heat-related illnesses.
“If you’re in a super hot room, if you have a fan, is it helpful? No. I think, if you have a fan, and you’re able to nebulize yourself … then fans can be helpful,” said Linden. “The fans are not infallible.”
Finally, be sure to check on your neighbors, parents and friends — especially older people who may live alone or are isolated, Linden said.
