ablation(redirected from subconjunctival ablation)
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ablation(ab-lay -shŏn) The loss of material from the surface of a moving body as a result of vaporization, friction, etc. For example, atmospheric atoms and molecules erode the surface of a meteoroid and damage the protective heat shield of a returning space shuttle.
in glaciology, the wasting of the mass of a glacier or snow cover as a result of thawing, evaporation, or mechanical removal—for example, wind ablation or the falling of icebergs. It is caused chiefly by climatic factors.
Three types of ablation are distinguished according to place of appearance: subglacial (or bottom), internal, and surface. The internal heat of the earth, springs (particularly warm ones) surfacing in the glacier bed, and heat caused by the friction of the glacier in its bed are some of the causes of subglacial ablation. Internal ablation is caused by friction between the glacier components and by the circulation of water and air. The glacier surface receives warmth predominantly from solar radiation and from the air. The thermal balance of the glacier surface is the basis of all surface ablation processes. The term “ablation” is sometimes used as well as a synonym for “surface washoff.”