ablation

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ablation
1. Removal of snow and ice by melting and by direct alteration from the solid to the gaseous phase (sublimation). The rate of loss is controlled chiefly by air temperature, wind velocity, humidity, rainfall, and solar radiation. Ablation on snowfields is also influenced by aspect, depth of snow, and the nature of the underlying surface. Ablation till is the glacial deposit that may be released. The ablation zone of a glacier is that area in which losses, including calving, exceed additions.

2. The removal of rock material, especially by wind action.

ablation
1. Removal of snow and ice by melting and by direct alteration from the solid to the gaseous phase (sublimation). The rate of loss is controlled chiefly by air temperature, wind velocity, humidity, rainfall, and solar radiation. Ablation on snowfields is also influenced by aspect, depth of snow, and the nature of the underlying surface. Ablation till is the glacial debris that may be released. The ablation zone of a glacier is that area in which losses, including calving, exceed additions.

2. Removal of rock material, especially by wind action.

ab·la·tion / əˈblāshən/ • n. 1. the surgical removal of body tissue. 2. the removal of snow and ice by melting or evaporation, typically from a glacier or iceberg. ∎  the erosion of rock. ∎  the loss of surface material from a spacecraft or meteorite through evaporation or melting caused by friction with the atmosphere. DERIVATIVES: ab·late / əˈblāt/ v.

ablation (ăb-lay-shŏn) n. the removal or destruction of tissue, a part of the body, or an abnormal growth by surgery, hormonal or other drugs, or heat. radiofrequency a. the destruction of abnormal conducting tissue in the heart in patients with supraventricular tachycardia by the use of radiofrequency energy delivered via catheter under X-ray and electrocardiographic guidance. See also endometrial (ablation).

ablation The wearing away of the outer layers of a body by melting, erosion, vaporization, or some other process due to aerodynamic effects as the body moves at high speed through a planetary atmosphere. Ablation can affect natural bodies such as meteoroids, or artificial objects such as spacecraft. Ablation of a spacecraft's protective heat shield prevents overheating of the spacecraft's interior during atmospheric entry.

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