This is SeaTalk: Ocean News from the University of Delaware.

Have you ever wondered why bay and ocean water doesn’t freeze like fresh water? Fresh water freezes as temperatures dip to 32 degrees Fahrenheit. But salt lowers the temperature at which water freezes. That’s why we use salt on roads to prevent the formation of ice. So for the saltiest water off Delaware’s Atlantic coast to freeze, the thermometer must drop to 28.6 degrees. As salt water begins to freeze, it develops as slush — it doesn’t form a continuous sheet as it would on a freshwater pond. That’s why during a Delaware winter you’re more likely to see a slushy surface of ice crystals along a bay shoreline, silently undulating as waves break beneath. This is SeaTalk, a public service announcement from the University of Delaware, the Delaware Sea Grant College Program, and this station.