Buzz
As summer temperatures soar to unprecedented levels, the allure of the beach and its inviting ocean waters becomes even more tempting. However, before you can dip your toes in the refreshing waves, you might need to navigate a stretch of sand so hot it feels like walking on fire. Sand, made up primarily of quartz and sometimes other minerals like calcite, feldspar, gypsum, basalt, and even tiny bits of shell or fish waste, absorbs solar energy through radiation, explains Paul Jarvis, a geologist and volcanologist at the University of Geneva. As the sun beats down, sand heats up and retains this warmth, with temperatures reaching as high as 140°F—enough to cause serious burns. Here’s how to keep your feet safe from this burning hazard.
1. CHOOSE THE RIGHT FOOTWEAR.
It may sound simple, but the type of shoes you wear makes all the difference. Materials like plastic, rubber (commonly used in flip-flops), foam resin (like the material found in Crocs), and neoprene (used in the Sand Socks favored by many beach volleyball players) provide a protective layer between your skin and the sand. This helps to reduce heat conduction—the process by which heat from the sand transfers to your feet. As a result, your feet are less likely to get burned, at least for a while. Flip-flops and other open shoes, though popular, should be avoided on especially hot days since they don’t shield your feet from the scorching sand.
2. CREATE A PATH WITH A COUPLE OF BEACH TOWELS.
If you’ve left your shoes behind in the car, you can still protect your feet by laying out a few towels to walk on, repeating this process until you reach your desired spot on the beach. The cotton fabric of the towel does a better job of blocking heat transfer to your feet than rubber soles, thanks to its lower thermal conductivity—the speed at which heat moves through a material, according to Paul Jarvis. However, because towels are thinner than shoes, heat can pass through more quickly. In other words, you’ll need to move quickly to keep your feet comfortable.
3. RUN QUICKLY …
The less time your feet spend in direct contact with the hot sand, the less heat can transfer to them. Running is an effective strategy for short distances or early morning beach trips before the sand has been heated by the sun’s rays. No matter how fast you run, however, some heat will still be conducted, and after a few steps, the burning sensation will inevitably set in.
4. … OR BURY YOUR FEET.
If you're burdened with a cooler and tote bags, try a technique used by professional beach volleyball players: digging your feet into the cooler sand as you walk, which allows your feet to make contact with the much cooler layers beneath the surface. Since sand has large gaps between its grains, it can't efficiently transfer heat deep into the sand bed, according to Paul Jarvis. So, dig in a few inches. This method of 'walking' is more like a slow shuffle, but it will help you avoid burns on your way to your destination.
5. MOISTEN THE SAND …
Water requires five times the amount of solar energy to heat up by 1°C (33.8°F) compared to sand, a property known as heat capacity. This means adding just a small amount of water to the sand can significantly raise the temperature threshold before the sand becomes uncomfortably hot, says Jarvis. You can carry a bucket of water and pour it slowly onto the sand beneath your feet as you walk. While not the most convenient method, it's helpful if you're near the water and need to make a quick trip, like running to the restroom or grabbing a snack. Simply grab one of the kids' sand-castle buckets. Wet sand is also much easier to walk and run on than dry sand.
6. … OR COOL DOWN YOUR FEET.
American professional beach volleyball player Sara Hughes has a go-to technique for handling hot sand: 'To cool down, I personally like to put water on my feet,' she told USA Volleyball's blog. Jarvis explains that since water has a higher heat capacity than human skin, wetting your feet keeps them colder, allowing you to stay on the beach longer before your skin reaches a temperature that causes burns. However, this is only a temporary fix, as your feet will dry quickly. Be sure to bring a bucket for this trick—you might need to dip your feet in several times before reaching your final destination.
7. SEEK OUT SHADE.
Since sand heats up quickly with little energy required to change its temperature, shaded areas will naturally feel much cooler. These spots are easiest to find in the early morning or during the evening when the Sun casts long shadows across the beach. Throughout the rest of the day, keep an eye out for shaded areas provided by lifeguard chairs, beach umbrellas, or palm trees, as they offer a much-needed respite for your feet.
8. CHOOSE A BEACH WITH LIGHTER SAND.
If you plan to go without shoes, choose your beach carefully. The heat capacity of the sand varies depending on the minerals it's made of, which can be hard to determine unless you conduct your own research. However, a good rule of thumb is that darker sands tend to absorb more heat, while lighter sands reflect more of the Sun's radiation, says Jarvis. 'Dark sand, such as that from volcanic rocks like basalt, absorbs more heat and heats up faster, making it potentially much hotter.' On the other hand, lighter-colored sand stays cooler under the sun.
