“How to Prepare for Climate Change” by David Pogue (Simon & Schuster, 2021) is the first practical guide to adapting to the new climate. It covers where to live; how to invest; how to insure; how to talk to your kids; how to build; what to grow; how to prepare a business; and how to prepare for flood, fire, drought, hurricane, heat waves, and tornadoes. 

This excerpt is from Chapter 10, “Preparing for Heat Waves.” 

Preparing for Heat Waves 

You could fill an internet with examples of heat records being broken recently: 

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  The last five years have been the hottest ever measured on the planet.  
  

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  September 2020 was the hottest month ever recorded.  
  
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  The hottest temperature ever reliably recorded was 130° F in Death Valley, California—on July 10, 2021. 
  
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  The July 2021 North American heat wave produced the hottest temperatures ever recorded in Canada (121.3°), Oregon (116°), and Washington state (118°).  
  

But these records are made—and guaranteed—to be broken, over and over again. Computer models predict that from 2050 to 2100, heat waves will triple in frequency. 

Figure 10-1. The 0 line represents the 1901–2000 average worldwide temperature, as measured by both land-based and sea-surface sensors. The downward bars indicate below-average temperatures; the upward ones indicate above average. 

Unfortunately, in most years, heat is the biggest killer of them all. In 2018, heat killed 50% more Americans than floods did, and three times as many people as hurricanes. In 2021, the Pacific Northwest heat wave killed over 700 people—and over a billion animals. 

Figure 10-2. Of all the extreme-weather monsters, heat is the deadliest. 

The bottom line: In the last 25 years, heat exposure has killed more people than hurricanes, lightning, tornadoes, floods, and earthquakes combined. 

Figure 10-3. In the United States, the Northern and Western states have warmed the fastest since 1991—look at Alaska! The Southeastern states have heated up but not nearly as much. (Darker spots have heated up more.) 

How Heat Affects Us 

Heat dries us out, weakens us, impairs our thinking, makes us more argumentative. It also stresses our hearts, which might not be an immediately obvious side effect.  

Ordinarily, a teaspoon’s worth of sweat, cumulatively evaporating from all over your body, can cool your bloodstream a full 2 degrees. (A liquid evaporating from any surface cools it down.) 

But when it’s humid out, sweat doesn’t evaporate from your skin, because it has no place to evaporate to. The air around you doesn’t want it; it’s already saturated with water vapor. That’s why humidity magnifies the effects of heat waves. 

The unfortunate payoff: 

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  Asthma. Hot air and humid air are both triggers for asthma attacks. To make matters worse, hot days are usually windless days. If the air is polluted, it just sits there, stagnant, and you’re breathing it. That’s why asthma and other lung problems get worse during heat waves. 
  

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  Heat cramps. When you lose enough water and salt, you start getting muscle spasms, especially if you’ve been playing sports or working outdoors. Consider these your early-warning system. Stop what you’re doing, start drinking water, and get out of the heat. 
  
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  Heat exhaustion. If you’ve been in extreme heat for a long time—a couple of days, for example—you might start sweating heavily; feeling your heart race; and feeling faint, dizzy, and tired. You may also get nausea and headache. Key symptom: Your skin is cold and clammy. 
  

This is really bad news. Stop what you’re doing, start drinking water, get out of the heat, and seek medical treatment fast. 

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  Heatstroke. This is the final stage of heat injury. Your body can’t control its own temperature anymore. Your internal temp spikes above 104°. Congratulations: You’ve got hyperthermia (heatstroke). 
  

You get confused, dizzy, and mumbly, with a splitting headache. Sometimes, you feel nauseated, your skin is flushed, you’re breathing fast, and your heart goes nuts, beating fast to try to cool you down. Key symptom: Skin is hot and dry. 

You might not even know what’s happening, because—unless you’ve been exercising—you’re not sweating. But unless you get emergency treatment fast, heatstroke can do damage to your brain (because it swells in your skull), heart, kidneys, and muscles. 

If you suspect that someone is having heatstroke, Cool them down. Get them into shade or air-conditioning; take off as many of their clothes as possible; spray them with water; and put cold, wet towels on their neck, armpits, and groin. 

The AC Problem 

Air conditioners are power beasts and environmental disasters. They’re the costliest items on your electric bill, accounting for half of it in hot weather.  

Another problem: Air conditioners work by pumping indoor hot air out of the building. The net effect of those thousands of air conditioners is, quite literally, to heat up the outdoors, by as much as 2 degrees. They contribute to the heat island effect, a measurable spike in temperature in densely populated areas. 

Figure 10-4. This is London, viewed from space with an infrared camera. The darkest spots are 5 degrees warmer than the lightest ones, even though the weather is identical. That’s the heat-island effect. 

Finally, all those air conditioners running simultaneously contributes to another common heat-wave side effect: Power blackouts. 

In other words, you should know how to cool yourself even without power. Read on. 

Indoors in the Heat Wave 

Once the heat wave is upon you, eliminate as many heat sources as possible. Don’t run big appliances (washer, dryer, dishwasher, oven, stove) until it gets cool at night; they pump heat into your house.  

Close the shades or curtains, especially on windows that face south and west. Instantly, you’ve created a midday temperature drop of an almost 20-degree difference. If you don’t have window coverings, hang some kind of improvised white drapes, or even fill the windows with reflectors made of foil-covered cardboard.  

Meanwhile: 

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  Keep the heat out. Keep exterior doors and windows closed during the hot part of the day.  
  
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  Let the air flow. Open all the interior doors of all the rooms. More air flowing means a cooler interior. 
  
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  Designate a “cool room.” A typical basement stays at around 55° all year long, no matter how hot or cold it is above the ground. A basement is a great place to hang out when it’s baking outside. 
  

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  Cool packs. Mattresses and couch cushions trap body heat. Fight back with refrigerated cold packs or even plastic water bottles, hot-water bottles, or buckwheat pillows you’ve chilled in the freezer. 
  
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  Cool shower. A short, lukewarm or even cool shower can drop your body temperature in seconds. Let your body and hair air-dry. There’s nothing to stop you from taking a few of these showers a day. 
  
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  Cool sheets. Chill your bedsheets in the freezer. They’ll feel amazing. 
  
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  Cool neck. If you apply your antiperspirant to the back of your neck, the skin there won’t get all sweaty and gross, and your hair won’t stick there to trap heat.  
  
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  Fans. Fans use only a tiny fraction of the power required for air conditioners, and pass the savings on to you. A ceiling fan, for example, costs about a penny an hour to run. Compare that with 36 cents for central air.  
  

A fan makes you feel cooler by whisking away your perspiration, just the way nature intended, and also by pushing your own body heat away from you. It can easily feel 10 degrees cooler next to a fan. 

If you have AC and a fan, you can raise your AC thermostat by 10 or 12 degrees and feel exactly as cool. 

Here’s the catch, however: Feeling cooler is not the same as being cooler. When the temperature indoors is above 95°, a fan can’t prevent you from getting heat illnesses. 

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  Swamp coolers. In dry areas, like the Southwest of the United States, you can save a lot of money by using a machine called an evaporative cooler—or, more entertainingly, a swamp cooler. 
  

Some homes have big, whole-house units the size of air conditioners, but you can also buy a personal-sized, $25 swamp cooler about the size of a toaster. 

Figure 10-8. An evaporative cooler, or swamp cooler, is like an inside-out dehumidifier. Instead of converting water vapor to liquid (and creating heat in the process), it converts water to vapor (and creating cooling). 

You plug it in and fill it with water. A fan blows air across wet pads; as the water evaporates, it gets cooler. 

In other words, this device is a mechanized version of sweat evaporating off your skin. What you feel near a swamp cooler is moving air that’s been cooled by water’s transformation into vapor. 

These coolers are far less expensive than air conditioners. They work great in places like Nevada, Utah, and Arizona, where the air could, frankly, use a little humidifying. 

Alas, these machines don’t produce cooling in humid places; the water simply doesn’t want to evaporate. 

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  Cooling centers. Use Google to find out where your neighborhood cooling centers are. These are public, air-conditioned spaces like libraries, shelters, community centers, movie theaters, and malls. In many cities, you can get free public transportation to these centers during a heat wave, too.  
  
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  Adjust your schedule. The hottest part of the day is roughly from 10 a.m. to 5 p.m. Anything active or hot that you can shift outside of those hours, you should shift.  
  

Sleeping in the Heat 

Nights during a heat wave without AC can be truly miserable. Fortunately, the worlds of science and commerce are always available to help: 

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  Sleep low. Heat rises. Drag a mattress to the lowest floor you’ve got.  
  

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  Fix your sheets. Cotton, percale, and linen are great sheet materials, because they’re breathable. But you can also buy hybrid-fabric sheets designed for cooling: lightweight, breathable, and moisture wicking, and heat-absorbent. They’re called things like Slumber Cloud Stratus, Comfort Spaces Coolmax, Sheex Micro-Balance, and Sleep Number True Temp. 
  
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  Dampen your sheets. If your sheets are cotton, try this classic trick: Get them wet, then wring them out. Their arrival on your body marks the official end of your “it’s so hot I can’t sleep” phase. 
  

Once the Air Cools Outside 

When the sun finally sets, and the air outside becomes cooler than it is inside, get all the hot air out. Open the windows, set up a cross breeze, and turn on the exhaust fans in your bathroom and kitchen. 

Medicine and Heat 

Your medicines aren’t little capsules of magic. They’re complex chemical mixtures, incredibly susceptible to temperature. Antibiotics, aspirin, hydrocortisone, test strips, hormone medicines (including thyroid meds and birth control pills), insulin, heart meds, and seizure drugs all lose potency or break down in the heat. 

The only solution is to keep meds cool and dry. Never leave them in a parked car, especially not in the trunk.  

If you must venture into the heat with insulin or antibiotics, buy cooling packs for them at the drugstore. 

For any meds, if you’re leaving a cool home for the day, take with you only what you’ll need. Leave the original bottle at home where it’s cooler. 

Outside in the Heat Wave 

Heat poses the greatest danger to people who have to be outdoors in it, like road workers, farmers, utility repair technicians—and homeless people, who have very few resources to protect themselves. 

Avoid exerting yourself outside, if you can help it. If you want to work out, for example, visit a gym or swim. 

If your home isn’t cool, spend the hottest part of the day somewhere that has air-conditioning, like a movie, a library, or a friend’s house.  

Working Outside 

But what if you must be outside in the heat? What if it’s your job? 

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  Take breaks. Heat + humidity + exertion = heat illness. You have control over one of those factors. Take frequent breaks. 
  
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  Eat for the heat. Digesting food heats up your body like a furnace. Eat smaller, more frequent meals, preferably juicy stuff like strawberries, melon, cold soup, Popsicles, Jell-O, diced fruit cups, applesauce, and Italian ices. 
  
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  Wear the lightweight, light-colored clothes. Dark colors absorb heat and make you hotter.  
  
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  Wear sunscreen. Sunburn impairs perspiration functioning and makes you feel hotter. 
  

Drinking More Water 

The more you sweat, the more water you lose. That’s why people get dehydrated so quickly on hot days. 

The golden rule: Drink enough so that your pee comes out clear. If it’s yellow or, worse, orange, you’re dehydrated. 

Even slight dehydration can bring you headaches, irritability, weakness at sports and work, and inability to concentrate. Dry eyes and blurry vision aren’t uncommon. If you’re very young or very old, dehydration can send you to the hospital. 

And if you’re dehydrated often, you can get urinary tract infections, kidney failure, and kidney stones. (Kidney stones are a side effect of climate change that people don’t talk about, maybe because they’re terrified; the pain is beyond description. What’s the connection? Heat leads to dehydration, and dehydration contributes to kidney-stone formation.) 

Of course, sweat isn’t just water. It also contains electrolytes—minerals like sodium, potassium, calcium, and magnesium—that your muscle and nerve cells need for everyday operation. Most of it is sodium, which is why sweat tastes salty. 

Lose enough of electrolytes, and you get cramping, dizziness, and headaches. 

If you find yourself drinking a lot of water in hot weather, find something to replenish your electrolytes. Gatorade will do it, but you can make your own facsimile by stirring half a teaspoon of salt and eight teaspoons of sugar into a quart of water. 

Eating a salty snack and washing it down with water is a worthy Plan B. 

Kids and Heat 

Children are especially vulnerable to heat waves. They run around a lot, they produce more heat than adults, they don’t drink much, and their little bodies can’t get rid of that heat as well, because they don’t sweat as much. 

When the going gets hot, therefore, you have a job to do, parents. 

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  Make sure your kids are drinking enough. 
  
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  Steer them toward wetter forms of fun, like running through sprinklers or swimming. (But watch them. About 350 kids under five drown every year in pools.) 
  
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  When they’re not in the water, they should be in the shade whenever possible. 
  
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  Slather the kids with sunscreen—every two hours or whenever they come out of the water. Yes, even if it’s cloudy. 
  

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  If it’s over 90° and humid, don’t let your kids play outside for more than 30 minutes at a time. 
  
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  More than 50 children die in hot cars every year. Most are under two years old (the kids, not the cars). 
  

Car interiors get hot incredibly fast—20 degrees every ten minutes—thanks to, of all things, the greenhouse effect. The sun’s reflected heat is trapped, and the car gets really hot. It can easily reach over 200° if the car’s interior is dark colored. Sadly, once a kid’s internal temperature reaches 107°, that’s the end. 

Here’s an idea: Whenever you put your kid in a car seat, put your wallet, purse, or phone back there, too. You’re a lot less likely to stride away and forget that you’ve left something valuable behind. 

Pets and Heat 

Dogs and cats, too, suffer in the heat. They have fur coats that they can’t remove, and they don’t sweat; their sole cooling mechanism is panting, which exchanges hot air from their lungs with cooler air outside. 

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  Signs of heat. The signs of pet heatstroke are heavy panting, intense thirst, restlessness or clumsiness, thick saliva, lethargy, lack of appetite, a dark tongue, fast heartbeat, throwing up, and bloody diarrhea. 
  

The treatment: Cool-down techniques like air-conditioning; spraying with water; lowering into cool water (but not ice water, which would cool the animal too fast); providing water to drink (but not forcing him to drink); wet towels on the stomach, chest, groin, and paws. Then get the dog to a vet as fast as possible; that’s the only way to rule out invisible problems like shock, organ damage, and clotting. 

As with humans, being old, sick, or overweight makes a pet more susceptible. Animals with flat faces—bulldogs, pugs, Persian cats—overheat more easily than other breeds, because it’s harder for them to pant. 

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  Take care taking walks. Paved surfaces absorb and store heat; when the air is 87°, the sidewalk can get up to 140°. If you must walk the dog on pavement, test it with your hand first. 
  

Avoid the hottest hours of the day, keep walks short, and don’t run. Provide plenty of water, shade, and swimming opportunities, if your dog is into that sort of thing. A haircut can keep your dog cooler, but don’t shave; the last inch of fur protects her from sunburn. (Don’t cut or shave cats. They’re more efficient than dogs at regulating temperature, and their fur is part of the system.) 

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  Interior car heat. Animal advocates stress that it’s never okay to leave an animal alone in a car, even if you run the AC or leave the window cracked. (A car with windows opened 1.5 inches is only 2 or 3 degrees cooler inside than a car with closed windows.) Hundreds of dogs die in hot cars every year. 
  

Tesla’s cars have a novel solution called Dog Mode. When you leave, the car maintains your temperature setting—70°, for example—and its screen says, in gigantic type, “My owner will be back soon. Don’t worry! The AC is on and it’s 70°F.” 

Figure 10-6. On a Tesla, you’re far less likely to get your window smashed by a well-meaning dog lover. 

People generally won’t alert authorities or smash your windows if they realize that the dog is comfortable. 

You may not own a Tesla, but there’s nothing to stop you from making a sign of your own when you have to leave your dog inside—briefly, responsibly, with water at hand and AC on.