What Hiking in One of the World’s Harshest Deserts Taught Me About Surviving Heat

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It was the heart of summer in the Namibian desert. There had been no rain on Brandberg Mountain for more than two years, so we each carried three gallons—24 pounds—of water. This sloshing liquid, combined with a week’s worth of food and camping supplies, made our packs crushingly heavy. And still, this was only enough water for two days.

I hiked with my Ovambu guides in the predawn dark for an hour before the sun broke the horizon. Then the temperature began to rise by the minute. Before 9 a.m. it was more than 100°F in the shade, if you could find it. The Brandberg is all rock, a vast cauldron of exfoliating granite with a few cactus-like trees. We hiked for a half hour, then hid beneath a boulder for a half hour. This would become our standard routine.

By noon it was 115°F in the shade. In the sun, the rocks were too hot to touch, like the top of a wood stove. It was so hot the soles of my boots delaminated and I had to use large safety pins run up through the rubber to secure them.

By 3 p.m., we had climbed 5,000 feet to the rim of the plateau and already drunk half our water. The top of the Brandberg is a Mars-like landscape of rolling red stone and random boulders. There is no vegetation other than spiky, spiny, bizarre plants that sprout from creases in the rock (and apparently only need water once a century).

We needed water immediately. If we didn’t find any, we’d be forced to turn around the next morning. We searched barren stone pool after stone pool, crossing swales of smooth granite, finally finding 6 inches of green sludge at the bottom of an 8-foot-deep stone hole. This was water leftover from the last rains more than 24 months earlier. We were ecstatic and camped right there.

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For a week we explored the famous rock paintings of the Brandberg, some almost 4,000 years old, all depicting a time when the land was lush and giraffes, lions, eland, and elephants flourished. Each day the temps rose above 110°F and still we hiked for hours upon hours. One morning we climbed 9,030-foot Köningstein, German for “king’s stone,” Namibia’s highest peak, hoping for a break in the heat, but it didn’t happen. My guides, a father and son team named Angula and Thomas, showed me red rock paintings that had only been seen by a few other people in the millennia since they were created.

Every evening we returned to our camp and went to the one source of water in hundreds of square miles. Using string and a cup, we pulled up water and filtered it. But the water was so scummy, the filter clogged permanently after several days and we were forced to use iodine instead. Still, it was water, the liquid of life, and we were thankful.

There are hotter places in the world, but I hope I never have the opportunity to visit them. Here are the lessons I learned from hiking in the heat of the Namibian desert.

Tip: In the desert, you may have to drink water out of stagnant, algae- or insect-larva-filled sources. Consider prefiltering your water through a t-shirt or bandana before treating it.

Key Lessons for Dealing with Heat

• Have a backup plan for when the waterhole you are absolutely sure has water is actually dry.
• Bring hard candy to suck on while hiking.
• Cotton kills? Not in extreme heat. Cotton retains moisture better than synthetics, and thus keeps you cooler (though it can limit range of motion).
• Wear a full-brimmed hat and extra-dark sunglasses at all times. Even with the hat, you can get burned by light reflected off the ground. Use sunscreen on any exposed flesh, like your face and the backs of your hands.
• Don’t hike during the middle of the day, when temps reach their peak. Crawl as far back beneath a boulder or inside a cave as you can. Read a book, take a nap. Bring airplane eyeshades.
• Rely on yourself, not your guides or companions, to ensure you will have water. I brought both the filter and the iodine. Without them, the nasty muck we found probably would have made us violently sick.
• Don’t wear shorts or short sleeves. When the ambient temperature is above your body temp, 98.6°F, more layers actually keep your body cooler. That’s why you see Bedouins and other desert dwellers wrapped up.
• Take off you boots and socks at every stop. This will keep your feet from baking and blistering. Change salty socks frequently.
• Know with certainty—absolute certainty—where your next source of water is and how long it will take to get there in severe conditions.
• Use a bladder with a mouthpiece rather than a bottle. You’ll always drink more. Always bring a backup water bag.
• If you’re working hard in extreme heat, drink 5 quarts of water a day. Add a pinch of electrolyte mix to each quart (go easy on sweeteners; too much sugar in the heat will make you sick).
• Plan your route to take advantage of terrain—shelves, ridges, ledges—and the arc of the sun so you can hike in the shade as much as possible.
• You need a pack with very good suspension to carry 20 to 30 pounds of water plus gear.
• Hike at night. LED headlamps last for dozens of hours. (In Namibia, I hiked very little at night because of the leopards, which were thirsty and hungry, and because the point of the trip was to view rock art.)
• Excessive heat, like excessive altitude, kills your appetite. Force yourself to eat.
• In open country, hike from shade to shade; half hour moving, half hour resting beneath a cactus, a bush, a boulder.
• Don’t wear gaiters, they make your feet sweat too much.
• Know the symptoms of heat exhaustion and heatstroke. Heat exhaustion you can recover from; heatstroke, in a wilderness desert, could quickly be fatal. Check each other at every rest stop for signs and symptoms.

Heat Stroke and Heat Exhaustion: Know the Signs

Pay attention to these symptoms and prevent a dangerous case of heat illness.

Signs and Symptoms of Heat Exhaustion

Go on high alert if you see these symptoms in yourself or others. Early treatment can prevent heatstroke, which can be fatal.

• Headache
• Dizziness and lightheadedness
• Weakness
• Nausea and vomiting
• Pale skin
• Profuse sweating
• Dark urine
• Increased heart rate

Signs and Symptoms of Heat Stroke

This occurs when your body is no longer able to regulate its temperature. Heatstroke can cause shock, brain damage, organ failure, and death.

• Fever (temperature above 104°F)
• Irrational behavior
• Extreme confusion
• Hot, red skin
• Rapid, shallow breathing
• Rapid, weak pulse
• Seizures
• Unconsciousness

Treatment for Heat Exhaustion and Heat Stroke

• With both heat exhaustion and heatstroke, your goal is to cool the victim as quickly as possible. Remove non-cotton clothing and have him lie down in the coolest place available.
• The ideal field treatment for heat stroke: immerse the victim in water. If there’s no pond or deep-enough watering hole nearby (likelier than not in the desert) you’ll need to improvise. Apply cool water or wet cloths to the person’s skin. Fan them and place cold compresses or ice on his neck, groin, and armpits.
• If the victim is alert and not vomiting, give him a sports drink or salted water (1 teaspoon per quart). They can drink about a cup every 15 minutes.
• Heat stroke is no joke: Treat it like an emergency and eek medical attention immediately. Don’t get complacent: Victims can relapse after appearing to recover.