This freak of nature occurs after heavy snow falls along the shores of large lakes and oceans. Thesnow is turned into ice by the motion of the waves, creating huge frozen ice balls.
Thousands of balls of ice the size of a football,huddle along the shore in a wonderful show. For this to happen the water temperature should be 0 ° C. A phenomenon known as "Lolly" by the fishermen of the Canadian Island of Cape Breton.
-The frozen surface or ice covered area should glide with ease to make a roller. -The ice must be covered with a 2 cm moist layer thick powder snow and the temperature must be close to the point where ice melts.
-The air temperature must be equal to or slightly above freezing, between 0 and 1 ° C.-The wind must be approximately 40 km / hour to roll the snow.
-A gust of wind takes the snow along like a spoonful of ice cream. Each gust of wind increases its size.
The size of the cylinders may reach severalcentimeters and one roller had a diameter of 70 cm.
Finally, when the roll is too heavy to bepushed by the wind or comes against anobstacle, it stops, leaving a trail behind.
Gravity also forms snow rollers. The snow falls from a tree on a slope and rolls down, forming a sphere.