{"id":18912,"date":"2019-12-13T00:30:30","date_gmt":"2019-12-13T00:30:30","guid":{"rendered":"https:\/\/www.lifeandnews.com\/articles\/?p=18912"},"modified":"2019-12-14T05:16:02","modified_gmt":"2019-12-14T05:16:02","slug":"winter-is-coming-5-essential-reads-about-snow-and-ice","status":"publish","type":"post","link":"https:\/\/www.lifeandnews.com\/articles\/winter-is-coming-5-essential-reads-about-snow-and-ice\/","title":{"rendered":"Winter is coming: 5 essential reads about snow and ice"},"content":{"rendered":"

Jennifer Weeks<\/a>, The Conversation<\/a><\/em><\/p>\n

As cold weather settles in across North America, some communities have already started up their snowplows, while others keep watchful eyes on the forecast. Snow and ice can wreck travel plans, but they also play important ecological roles. And frozen water can take amazing forms. For days when all talk turns to winter weather, we spotlight these five stories from our archives.<\/p>\n

1. The strange forms water can take<\/h2>\n

Beyond snowflakes and icicles, frozen water can behave in surprising ways<\/a>. For example, during very cold snaps, lakes can appear to steam like a sauna bath.<\/p>\n

As Colorado State University atmospheric scientist Scott Denning<\/a> explains, this happens because the liquid water in the lake can\u2019t be colder than the freezing point \u2013 about 32 degrees Fahrenheit. As water evaporates from the relatively warm lake into the cold dry air, it condenses from vapor (gaseous water) to tiny droplets of water in the air, which look like steam.<\/p>\n

When it gets extremely cold, ice can form on the ocean\u2019s surface. Waves break it up, so the water starts to look like an undulating slurpee. \u201cFor anyone willing to brave the cold, it\u2019s wild to stand by the shore and watch the smoking slushy sea with its slow-motion surf,\u201d Denning writes.<\/p>\n

2. How road salt tames ice<\/h2>\n

When a big storm is forecast, utility trucks often will head out to pre-treat streets and highways, typically spraying rock salt or saltwater solutions. But contrary to popular belief, salt doesn\u2019t melt ice<\/a>.<\/p>\n

Water freezes at 32 degrees Fahrenheit, but mixing it with salt lowers its freezing point. \u201cThe salt impedes the ability of the water molecules to form solid ice crystals,\u201d explains Julie Pollock<\/a>, assistant professor of chemistry at the University of Richmond. \u201cThe degree of freezing point depression depends on how salty the solution is.\u201d When dry salt is spread on ice, it relies on the sun or the friction of car tires to melt the ice, then keeps it from re-freezing.<\/p>\n

Pulses of salt can harm plants, water bodies and aquatic organisms when it washes off of roads \u2013 especially during spring runoff, which can carry huge doses. Researchers are working to find more benign options, and are currently studying additives including molasses and beet juice.<\/p>\n