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As the weather gets colder, we start wearing
jackets, and most of us stop thinking about the sun. But the sun's rays can be
just as harmful when it's cold and cloudy outside. "Any exposed area of
your body can still get sunburned," Dr. Apple Bodemer, an associate
professor at the University of Wisconsin-Madison, told Live Science.
Whether you spend a day on the slopes, skating
on a pond or clearing snow out of your driveway, your face is still getting
exposed to the sun's radiation in the form of ultraviolet (紫外线) (UV) light, which can go deep into your skin cells causing DNA
damage, according to Bodemer.
The sun's long ultraviolet A (UVA) waves can
cause earlier aging, sunspots and wrinkles, while its short ultraviolet B (UVB)
rays are known for causing skin reddening and burns.
Skin damage caused by UV exposure increases over
time. More exposure to radiation contributes to more severe damage, even skin
cancer. In addition, snow and ice can also make sun damage worse. They reflect
up to 80 percent of UV rays reaching the ground. That means you get hit from
both the sky and the ground. And skiers and snowboarders increase their risk of
getting sunburned even more because UV exposure increases at higher altitudes.
"Generally, the biggest factor for sun-sensitivity
is how pale your skin is," he said. "But, the reality is that even
the darkest individual can get sun damage."
Luckily, the solution for protecting your skin
is simple: Wear sunscreen every day. Rigel recommended using sunscreen with a
sun protection factor (SPF) of at least 30, and going higher at high altitudes.
As a rule of thumb, SPF 30 will block 97 percent of UVB rays, SPF 50 blocking
98 percent, and SPF 100 blocking 99 percent. Whatever kind of sunscreen you
use, it's important to apply SPF about once every 2 hours.
Rigel also suggested sunscreens with "broad
spectrum (光谱)"—to protect against both UVB and UVA
rays—as well as sunscreens that are water resistant for up to 80 minutes. That
way, you can go about your day without it wearing off too quickly.