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a hummock having a core of silty and clayey mineral soil which may show evidence of cryoturbation.
the total infrared radiation emitted from the earth's surface; to be carefully distinguished from effective terrestrial radiation, atmospheric radiation, and insolation.
process by which warm water erodes iceberg above the waterline
the difference between the outgoing infrared (longwave) terrestrial radiation of the earth's surface and the downward infrared counter-radiation from the atmosphere.
the inverse of electrical resistivity.
the dielectric constant (or relative permitivity), electrical conductivity and electrical resistivity are the major electrical properties governing the flow of electric current through frozen ground.
the property of a material that determines the electrical current flowing through a centimetre cube of the material when an electrical potential is applied to opposite faces of the cube.
an oscillation of the electric or magnetic field associated with the propagation of energy; characterized by their wavelengths and amplitude; propagate at the speed of light.
the amount of electromagnetic energy (primarily at wavelengths longer than 1.0 micrometer) that an object emits; for example, the earth emits longwave radiation primarily in the infrared part of the electromagnetic spectrum, but also in longer microwave wavelengths; the emissivity of an object varies as the fourth power of its absolute temperature.
an arch-shaped ridge of moraine found near the end of a glacier.
dust and/or rock inside a glacier. This debris can become lodged in glacial ice after falling through crevasses.
ground ice developed in epigenetic permafrost, or in previously formed syngenetic permafrost.
an ice wedge developed in epigenetic permafrost, or in previously formed syngenetic permafrost.
permafrost that formed through lowering of the permafrost base in previously deposited sediment or other earth material.
the line of latitude 0°, which is equidistant from the poles, and which separates the Northern Hemisphere from the Southern Hemisphere.
snow metamorphism that occurs under relatively consistent temperature conditions.
boundary between the accumulation area and ablation area where the mass balance is zero.
snow metamorphism that occurs when there are large differences in convex and concave portions of a crystal.
permafrost that is in thermal equilibrium with the existing mean annual surface or sea-bottom temperature and with the geothermal heat flux.
zone of a glacier in which the amount of precipitation that falls is equal to the amount that melts the following summer.