{"id":38779,"date":"2025-02-17T13:45:00","date_gmt":"2025-02-17T13:45:00","guid":{"rendered":"https:\/\/www.lifeandnews.com\/articles\/?p=38779"},"modified":"2025-02-18T07:50:31","modified_gmt":"2025-02-18T07:50:31","slug":"why-do-skiers-sunburn-so-easily-on-the-slopes-a-snow-scientist-explains","status":"publish","type":"post","link":"https:\/\/www.lifeandnews.com\/articles\/why-do-skiers-sunburn-so-easily-on-the-slopes-a-snow-scientist-explains\/","title":{"rendered":"Why do skiers sunburn so easily on the slopes? A snow scientist&nbsp;explains"},"content":{"rendered":"\n<p><a href=\"https:\/\/theconversation.com\/profiles\/steven-r-fassnacht-1242332\">Steven R. Fassnacht<\/a>, <em><a href=\"https:\/\/theconversation.com\/institutions\/colorado-state-university-1267\">Colorado State University<\/a><\/em><\/p>\n\n\n\n<p>It\u2019s extremely easy to get sunburned while you\u2019re skiing and snowboarding in the mountains, but have you ever wondered why?<\/p>\n\n\n\n<p>While it\u2019s true that you\u2019re slightly closer to the Sun when you\u2019re high in the mountains, that isn\u2019t the reason.<\/p>\n\n\n\n<p>If you go up 1 mile (1.6 km), about <a href=\"https:\/\/www.snow-online.com\/highest_ski-resorts\/colorado\">the elevation<\/a> from Denver to the peaks of resorts such as Vail or Copper Mountain, you\u2019re less than 1 millionth of a percent closer to the Sun \u2013 that\u2019s nothing. Since the Earth\u2019s orbit is an ellipse and not a circle, the planet is about <a href=\"https:\/\/science.nasa.gov\/learn\/basics-of-space-flight\/chapter2-1\/#h-revolution-of-earth\">1.7% closer to the Sun<\/a> in early January compared with its annual average. This means skiers get about <a href=\"https:\/\/energyeducation.ca\/encyclopedia\/Inverse_square_law\">3.3% more<\/a> Sun in January than average for the year \u2013 so, not much more.<\/p>\n\n\n\n<p>Being 1 mile higher up does mean the atmosphere is thinner, so there are fewer particles to block the <a href=\"https:\/\/www.epa.gov\/sites\/default\/files\/documents\/sunuvu.pdf\">ultraviolet radiation that causes<\/a> sunburns.<\/p>\n\n\n\n<p>But the big reason your skin is more likely to burn has to do with all that fresh powder that skiers and snowboarders crave, especially on perfect, blue-sky days. I\u2019m a <a href=\"https:\/\/sites.warnercnr.colostate.edu\/srf\/\">snow scientist<\/a> at Colorado State University and an avid skier. There are many ways that snow conditions affect how much your skin will burn.<\/p>\n\n\n\n<h2>Fresh snow is very reflective<\/h2>\n\n\n\n<p>When you\u2019re out in the snow, a lot of the solar radiation your skin receives is reflected from the snow itself. The amount of radiation reflected is <a href=\"https:\/\/scied.ucar.edu\/learning-zone\/how-climate-works\/albedo-and-climate\">known as albedo<\/a>.<\/p>\n\n\n\n<p>Fresh powder snow can have an <a href=\"https:\/\/doi.org\/10.1017\/jog.2017.54\">albedo of almost 95%<\/a>, meaning it reflects almost all of the Sun\u2019s radiation that hits it. It\u2019s much more reflective than older snow, which becomes less shiny. <a href=\"https:\/\/snowflakebentley.com\/images\">Fresh snow<\/a> has a lot of surfaces to reflect the Sun\u2019s rays. As snow ages, the snow crystal becomes more round and there are <a href=\"https:\/\/doi.org\/10.5194\/cp-14-697-2018\">fewer surfaces to reflect light<\/a>.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img src=\"https:\/\/images.theconversation.com\/files\/649056\/original\/file-20250214-15-xqgnx1.JPG?ixlib=rb-4.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip\" alt=\"Snow crystals with angular designs. The photo was shot in Fort Collins, Colo., in 2022.\" \/><figcaption>Fresh snow has lots of planes to reflect the Sun\u2019s rays, more so than older snow. Steven Fassnacht\/Colorado State University, <a href=\"http:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY<\/a><\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"https:\/\/images.theconversation.com\/files\/649057\/original\/file-20250214-17-su9qbg.JPG?ixlib=rb-4.1.0&amp;q=45&amp;auto=format&amp;w=1000&amp;fit=clip\"><img src=\"https:\/\/images.theconversation.com\/files\/649057\/original\/file-20250214-17-su9qbg.JPG?ixlib=rb-4.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip\" alt=\"Older snow after it has melted somewhat is rounder and darker. This was shot in Fort Collins, Colo., in 2025.\" \/><\/a><figcaption>Older snow isn\u2019t as reflective as it melts and the grains become rounder. Steven Fassnacht\/Colorado State University, <a href=\"http:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY<\/a><\/figcaption><\/figure>\n\n\n\n<p>Having lots of fresh snow increases albedo because the Sun penetrates into the powder, reflecting off the small, newly fallen crystals. Think about starting a car after 6 inches of fresh snow fell. Some light still makes its way through the snow-covered windshield.<\/p>\n\n\n\n<p>Having only an <a href=\"https:\/\/hdl.handle.net\/10217\/234162\">inch of powder on crust<\/a> is not as reflective as knee-deep fresh powder. <a href=\"https:\/\/doi.org\/10.5194\/tc-10-329-2016\">Shallow snow<\/a> is less reflective. <\/p>\n\n\n\n<p>A lot of people want to ski on what are known as <a href=\"https:\/\/science.howstuffworks.com\/nature\/climate-weather\/atmospheric\/bluebird-day.htm\">bluebird days<\/a>, when there is deep, fresh powder under a clear blue sky following a big snow dump. However, this provides the perfect conditions to burn from two directions: lots of Sun coming down from above and high albedo reflecting it back to your face from below. Clouds block sunlight, with <a href=\"https:\/\/doi.org\/10.3390\/rs9070690\">only about one-third<\/a> of the Sun\u2019s radiation making it through a fully overcast sky.<\/p>\n\n\n\n<h2>Which side of the mountain also matters<\/h2>\n\n\n\n<p>Where you are on the mountain also makes a difference.<\/p>\n\n\n\n<p>The slope and the direction that the slope faces, <a href=\"https:\/\/avalanche.org\/avalanche-encyclopedia\/terrain\/slope-characteristics\/aspect\/\">called aspect<\/a>, also influences the intensity of the Sun on a surface. <a href=\"https:\/\/doi.org\/10.1029\/2004JD004617\">North-facing slopes<\/a> in the Northern Hemisphere get less direct sunlight in the winter, when the Sun is farther south in the sky, so they stay cooler.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img src=\"https:\/\/images.theconversation.com\/files\/648797\/original\/file-20250213-15-oikecg.jpg?ixlib=rb-4.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip\" alt=\"A clear, brilliant blue sky over bright white snow, punctuated by pine trees and mountains in the background.\" \/><figcaption>Ironton Park, near Ouray, Colo., on a clear blue day in February 2025. Steven Fassnacht\/Colorado State University, <a href=\"http:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY<\/a><\/figcaption><\/figure>\n\n\n\n<p>A lot of the runs at Northern Hemisphere ski resorts face north, so the snow melts slower. The <a href=\"https:\/\/doi.org\/10.3390\/glacies2010001\">snow also varies<\/a> from the top of the mountain to the base. There is more snow up high, and the snow melts slower there, so the albedo is higher at the top of the mountain than at the base.<\/p>\n\n\n\n<h2>How to reduce the risk of sunburn<\/h2>\n\n\n\n<p>To avoid sunburns, skiers and snowboarders need to take all of those characteristics into account.<\/p>\n\n\n\n<p>Because solar radiation is reflecting back up, people out in the snow should put sunscreen on the bottom of their noses, around their ears and on their chins, as well as the usual places.<\/p>\n\n\n\n<p>Most sunscreen also needs to be reapplied <a href=\"https:\/\/www.hopkinsmedicine.org\/health\/wellness-and-prevention\/sunscreen-and-your-morning-routine\">every two hours<\/a>, particularly if you\u2019re likely to sweat it off, wipe it off, or wear it off while playing on the slopes. However, surveys show that <a href=\"https:\/\/doi.org\/10.1016\/j.jaad.2010.11.044\">few people remember<\/a> to do this. Wearing <a href=\"https:\/\/www.epa.gov\/sites\/default\/files\/documents\/sunuvu.pdf\">clothing with UV protection<\/a> to cover as much skin as possible can also help.<\/p>\n\n\n\n<p>These methods can help protect your skin from burning and the <a href=\"https:\/\/www.skincancer.org\/risk-factors\/sunburn\/\">risks of cancer and premature aging<\/a> that come with it. Snow lovers need to remember that they face higher sunburn risks on the slopes than they might be accustomed to.<\/p>\n\n\n\n<p><a href=\"https:\/\/theconversation.com\/profiles\/steven-r-fassnacht-1242332\">Steven R. Fassnacht<\/a>, Professor of Snow Hydrology, <em><a href=\"https:\/\/theconversation.com\/institutions\/colorado-state-university-1267\">Colorado State University<\/a><\/em><\/p>\n\n\n\n<p>This article is republished from <a href=\"https:\/\/theconversation.com\">The Conversation<\/a> under a Creative Commons license. Read the <a href=\"https:\/\/theconversation.com\/why-do-skiers-sunburn-so-easily-on-the-slopes-a-snow-scientist-explains-249858\">original article<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Steven R. Fassnacht, Colorado State University It\u2019s extremely easy to get sunburned while you\u2019re skiing and snowboarding in the mountains, but have you ever wondered why? While it\u2019s true that you\u2019re slightly closer to the Sun when you\u2019re high in the mountains, that isn\u2019t the reason. If you go up 1 mile (1.6 km), about [&hellip;]<\/p>\n","protected":false},"author":56,"featured_media":38780,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[15534,292,1862,42,10,118,3410],"tags":[10086,1907,885,891,886,860,14506,10183,4193,16048,12284,11776],"_links":{"self":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/38779"}],"collection":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/users\/56"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/comments?post=38779"}],"version-history":[{"count":1,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/38779\/revisions"}],"predecessor-version":[{"id":38781,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/38779\/revisions\/38781"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/media\/38780"}],"wp:attachment":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/media?parent=38779"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/categories?post=38779"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/tags?post=38779"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}