8 Science-Backed Tips to Keep Your Feet From Burning on Hot Sand

iStock
iStock

With temperatures hitting record highs this summer, beaches—and their promise of cool ocean dips—beckon. But to reach the waves, it's likely you'll first have to cross an expanse of foot-scalding sand. Sand is made up of decomposed rock—quartz, mostly, but also calcite, feldspar, gypsum, or basalt, sometimes with a smattering of shell, coral, or fish poop tossed in—and according to Paul Jarvis, a geologist and volcanologist at the University of Geneva, it receives solar energy via the process of radiation. The composition of sand causes it to heat up as the day progresses and to retain that heat, reaching temperatures as high as 140°F—sufficient to inflict third-degree burns. Here are tips for protecting your soles from this painful outcome.

1. WEAR THE RIGHT KIND OF SHOES.

This seems obvious, but the level of protection you get depends on the kind of shoe you're wearing. Materials such as plastic and rubber (what many soles are made of), foam resin (the stuff of Crocs), and the neoprene base of the Sand Socks that many beach volleyball players swear by provide a barrier between skin and sand. This helps cut down on conduction—the transfer of heat from the warmer surface of the sandy beach to the cooler surfaces of your feet. As a result, your feet are protected (at least temporarily) from blistering. And though they're likely the first shoes you picture when you think of the beach, flip-flops and other open shoes should be avoided on especially scorching days, because they let the hot sand in.

2. MAKE A PATH USING A COUPLE OF BEACH TOWELS.

Forgot your shoes in the car? You can protect your feet by rolling out a couple of towels to step on, repeating the process until you reach your coveted beach spot. The cotton of your towel is better at quelling heat transfer to your feet than the rubber soles of your shoes are due to what scientists call a lower thermal conductivity—“the measure of how fast heat can be conducted through the material,” Jarvis tells Mental Floss. However, your towel is also thinner than your shoe bottoms, and heat conducts faster through thin objects. In other words, you’ll have to hurry if you want to keep your feet cool.

3. RUN FAST …

The less time the soles of your feet spend touching the sand, the less time there is for conduction. But sprinting is probably a technique best reserved for covering short distances or for morning beach visits, before the sand has had a chance to soak up the solar rays for several hours and achieve maximum temperature. Because no matter how fast you run, conduction is still happening, and after some strides, your feet will eventually begin to feel the burn.

4. … OR BURROW YOUR FEET.

If you're loaded down with a cooler and tote bags, try a technique favored by professional beach volleyball players: Burrowing your tootsies as you walk, which puts your feet in contact with the much cooler sand beneath the surface. Because there are large gaps between grains of sand, it's “unable to efficiently transmit heat … through the sand bed to [its] deeper levels,” Jarvis says. So dig in a few inches. This way of “walking” is actually more of a slow shuffle, but it'll get you to your destination sans burns.

5. WET THE SAND …

It takes five times as much solar energy to heat water 1°C (33.8°F) as it does to heat sand by the same amount (what's technically known as heat capacity). So “adding just a small amount of water to the sand can dramatically increase the amount of heat the sand surface needs to receive before it gets hot,” Jarvis says. You can replicate the effect by toting a bucket of water and tossing its contents under your feet little by little as you go. While not the easiest method, it could be a solution for when you're already near the water and have to, say, run to the restroom or buy a snack. Just grab one of the kids' sand-castle buckets. Wet sand is also a lot less arduous to walk and run on than dry sand.

6. … OR YOUR FEET.

American pro beach volleyball player Sara Hughes has a go-to sand strategy: “To cool down, I personally like to put water on my feet,” she told USA Volleyball's blog. According to Jarvis, because water has a higher heat capacity than human skin, having wet—and therefore colder—feet means "you can be exposed to the beach for longer before your skin reaches a temperature at which it will burn.” Obviously, this is a highly temporary solution, since your feet will quickly dry. So bring the bucket for this tactic too: You might have to dip your feet into the water several times before reaching your ultimate destination.

7. FOLLOW THE SHADE.

Since it doesn’t take a lot of energy to change the temperature of sand, areas in shadow will feel noticeably cooler to the touch. It's easier to find those spots early in the morning or at the onset of evening, when the Sun is at an angle to the beach; the rest of the day, keep an eye out for shadowed spots made by the lifeguard chair, beach umbrellas, or palm trees to give your feet relief.

8. FIND A LIGHT-COLORED BEACH.

Should you opt to go shoe-less, choose your sand wisely. The heat capacity of the sand on any beach you visit is dependent on what minerals it’s comprised of—a challenge to know unless you do your own scientific studies, beach by beach. However, a general rule of thumb is that hotter beaches come with darker sands—and the opposite is also true. “Light-colored sand reflects, as opposed to absorbs, a significant proportion of the Sun’s radiation,” Jarvis says. “Dark sand, such as that originating from volcanic rocks [like basalt], is much more heat absorbent, meaning it will heat up quicker and therefore, potentially become much hotter.”

Keep Your Cat Busy With a Board Game That Doubles as a Scratch Pad

Cheerble
Cheerble

No matter how much you love playing with your cat, waving a feather toy in front of its face can get monotonous after a while (for the both of you). To shake up playtime, the Cheerble three-in-one board game looks to provide your feline housemate with hours of hands-free entertainment.

Cheerble's board game, which is currently raising money on Kickstarter, is designed to keep even the most restless cats stimulated. The first component of the game is the electronic Cheerble ball, which rolls on its own when your cat touches it with their paw or nose—no remote control required. And on days when your cat is especially energetic, you can adjust the ball's settings to roll and bounce in a way that matches their stamina.

Cheerable cat toy on Kickstarter.
Cheerble

The Cheerble balls are meant to pair with the Cheerble game board, which consists of a box that has plenty of room for balls to roll around. The board is also covered on one side with a platform that has holes big enough for your cat to fit their paws through, so they can hunt the balls like a game of Whack-a-Mole. And if your cat ever loses interest in chasing the ball, the board also includes a built-in scratch pad and fluffy wand toy to slap around. A simplified version of the board game includes the scratch pad without the wand or hole maze, so you can tailor your purchase for your cat's interests.

Cheerble cat board game.
Cheerble

Since launching its campaign on Kickstarter on April 23, Cheerble has raised over $128,000, already blowing past its initial goal of $6416. You can back the Kickstarter today to claim a Cheerble product, with $32 getting you a ball and $58 getting you the board game. You can make your pledge here, with shipping estimated for July 2020.

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A Prehistoric Great White Shark Nursery Has Been Discovered in Chile

Great white sharks used prehistoric nurseries to protect their young.
Great white sharks used prehistoric nurseries to protect their young.
solarseven/iStock via Getty Images

Great white sharks (Carcharodon carcharias) may be one of the most formidable and frightening apex predators on the planet today, but life for them isn’t as easy as horror movies would suggest. Due to a slow growth rate and the fact that they produce few offspring, the species is listed as vulnerable to extinction.

There is a way these sharks ensure survival, and that is by creating nurseries—a designated place where great white shark babies (called pups) are protected from other predators. Now, researchers at the University of Vienna and colleagues have discovered these nurseries occurred in prehistoric times.

In a study published in the journal Scientific Reports, Jamie A. Villafaña from the university’s Institute of Palaeontology describes a fossilized nursery found in Coquimbo, Chile. Researchers were examining a collection of fossilized great white shark teeth between 5 and 2 million years old along the Pacific coast of Chile and Peru when they noticed a disproportionate number of young shark teeth in Coquimbo. There was also a total lack of sexually mature animals' teeth, which suggests the site was used primarily by pups and juveniles as a nursery.

Though modern great whites are known to guard their young in designated areas, the researchers say this is the first example of a paleo-nursery. Because the climate was much warmer when the paleo-nursery was in use, the researchers think these protective environments can deepen our understanding of how great white sharks can survive global warming trends.