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Ice dam forming on slate roof. An ice dam is an ice build-up on the eaves of sloped roofs of heated buildings that results from melting snow under a snow pack reaching the eave and freezing there. Freezing at the eave impedes the drainage of meltwater, which adds to the ice dam and causes backup of the meltwater, which may cause water leakage ...
Photograph taken 21 March 2010 in Norwich, Vermont. Frost heaving (or a frost heave) is an upwards swelling of soil during freezing conditions caused by an increasing presence of ice as it grows towards the surface, upwards from the depth in the soil where freezing temperatures have penetrated into the soil (the freezing front or freezing boundary).
The wall of this ice tube is about 0.1 mm (0.004 in) and the width 5 mm (0.2 in). As a result of this growth process, the interior of a growing icicle is liquid water. The growth of an icicle both in length and in width can be calculated and is a complicated function of air temperature, wind speed, and the water flux into the icicle. [3]
The emergence of needle ice has been recognized as a geomorphic agent of soil disturbance, causing a number of small-scale landforms. [8] Needle ice phenomena play a particularly significant role in patterned ground in periglacial environments. [8] The growth of needle ice lifts a detached, frozen soil crust riding on top of the layer of ice.
The formation of ice spikes is related to the shape of the water body, the concentration of dissolved impurities, air temperature and circulation above the water. [3] Spikes that grow from a crystallite formed below the surface of the water may project from the ice sheet at a steep angle, rather than perpendicular to it. [5]
Ice jacking is a continuous process that occurs during the winter in areas near lakes. The process starts when the ice begins to crack. When water then fills in those gaps, the process repeats and continues until there is a wall of ice surrounding the lake's shoreline, sometimes reaching up to three feet.
Ice dams on roofs form when accumulated snow on a sloping roof melts and flows down the roof, under the insulating blanket of snow, until it reaches below freezing temperature air, typically at the eaves. When the meltwater reaches the freezing air, ice accumulates, forming a dam, and snow that melts later cannot drain properly through the dam ...
Ice pellets form when a layer of above-freezing air is located between 1,500 and 3,000 meters (5,000 and 10,000 ft) above the ground, with sub-freezing air both above and below it. This causes the partial or complete melting of any snowflakes falling through the warm layer (the French term for sleet, neige fondue, literally means "melted snow ...