When the first rays of sunshine arrive after a long winter, all of Germany rejoices in the arrival of spring with sunshine and mild temperatures. But the joy of sunshine is not always unclouded. In spring, an ozone hole can form over Germany due to the so-called polar vortex. The polar vortex is a low-pressure area that rotates in the stratosphere above the North Pole in winter. If this vortex shifts unusually far to the south, then the ozone hole can also increase. Because the polar vortex leads to the formation of ozone-depleting gases called chloroxides, the ozone hole over Europe increases. Chlorine oxide concentrations were twice as high as in average winters when measured by a Russian research aircraft.
Stubborn legacy
Some of the chlorine that is dangerous to the ozone layer still comes from propellants in aerosol cans, although these have been banned for several years. However, because chlorine compounds rise slowly into the stratosphere and chlorine oxides keep forming after ozone destruction, their overall concentration decreases only slowly. In the polar vortex it gets very cold. Chlorine oxide forms on ice crystals of polar stratospheric clouds within the polar vortex. In sunlight, the chlorine oxide reacts very aggressively with the ozone in the stratosphere. Thus, ozone is depleted and thus the ozone layer loses its filtering effect for the sun’s UV rays.
Not without my sunscreen!
For sunny days, this means sunscreen is the order of the day! True, in spring the sun is still relatively low on the horizon and has to penetrate a very large layer of atmosphere. Therefore, the risk of sunburn is lower in the lowlands. Sensitive people should, however, ensure adequate protection from the sun here as well. In contrast, the situation becomes more problematic in the mountains. Tobogganers, skiers and snowboarders are particularly vulnerable to the sun under these conditions. In the mountains, the greater proximity to the sun already ensures significantly stronger UV radiation; the reflection of the sun by the white snow does the rest.
Frostbite in the sunshine?
In bright sunshine, people are often tempted to neglect sun protection. But in fact, just like in summer, you have to pay attention to the exposure times of sunscreen products on the slopes. Whether sunscreen or sun milk: the product should be allowed to act on the skin for at least 30 minutes before going out into the sun.
Those who sweat a lot during winter sports should apply a water-repellent sunscreen that cannot be wiped off by snow and sweat. In addition, sunscreens with a high water content can cause frostbite directly on the skin, because temperatures below 0 C often occur on the skin when skiing due to the wind. In this temperature range, only a special cold protection balm that is water-free and particularly rich in lipids can prevent impending frostbite.
By the way: sunscreens do not last for years, it is best to get a new one every year! Do not forget your lips! The sensitive skin of the lips, which is only about 1/20 of a millimeter thick, is also attacked by the winter sun. A nourishing lipstick with built-in UV protection compensates for the missing pigments of the lips.
UV index
The UV index rates sun intensity and sunburn risk on a scale of 1-8.
- A UV index of 2 – 4 means already for a typical Central European sunburn risk for half an hour in the sun without sunscreen.
- If the UV index is greater than 7, the radiation exposure has already increased to a very large extent. Even those who are exposed to the sun for less than 20 minutes can get burned. Protective measures are therefore absolutely necessary.
Based on the UV index and the individual skin type, everyone can decide on his personally appropriate protective measures. Since the UV index is internationally uniform, for example, a UV index 7 in Germany is to be evaluated in the same way as in the Swiss Alps or in Canada.
