Icicles typically form on days when the outdoor air temperature is subfreezing but sunshine warms and melts some snow or ice. As it drips off your roof, a water droplet freezes when it loses its heat to the cold air. An icicle starts with a few frozen droplets. When it reaches a certain size, drops begin to drip along the side of the structure. "The water will run down the sides of the formation evenly in a thin film and freeze on the way down," said University of Arizona physicist Martin Short, another member of the study team. "This sort of freezing, thin film of water is what leads to the eventual icicle shape." [from 'Icicle Formation Mystery Solved' at Live Science (www.livescience.com/1074-icicle-formation-mystery-solved.html)]

Image of 'ICICLE WINDOW' from Mountain Photography by Jack Brauer [www.mountainphotography.com]

You need to login or register to write reviews. It's quick! We only ask four questions to new members.