Ablation at the surface of the glacier, generally measured as the lowering of the surface with respect to the summer surface, corrected for the increase in density of any residual snow and firn and mu
ltiplied by the density of the lost mass.
Accumulation at the surface of the glacier, generally measured as the rise of the surface with respect to the summer surface multiplied by the density of the added mass.
The ratio, expressed as a percentage, of the amount of electromagnetic radiation reflected by the earth's surface to the amount incident upon it. Value varies with wavelength and with the surface comp
osition. For example, snow and ice vary from 80% to 85% and bare ground from 10% to 20%.
A distinct soil micromorphology, resulting from the effects of freezing and thawing processes, in which coarser soil particles have vertical or near-vertical orientation.
The SI name of the derived unit kg m-2, mass per unit area. It can be helpful to regard the product of a thickness and a density as a surface density. For example mass balance, when expressed in speci
fic units, is a surface density.
The rate at which a small object in free fall near the surface of a body is accelerated by the gravitational force of the body: g = GM / R^2, where G is the gravitational constant, and M and R are the
mass and radius of the object. The surface gravity of Earth is equal to 980 cm s^-2.
1. Fernlike ice crystals formed directly on a snow surface by deposition; a type of hoarfrost. 2. Hoarfrost that has grown primarily in two dimensions, as on a window or other smooth surface.
The deposition (sublimation) of ice crystals on a surface which occurs when the temperature of the surface is colder than the air above and colder than the frost point of that air.
The sum of surface accumulation and surface ablation. This is the sense in which the term is understood in descriptions of measurements by the glaciological method, in which the internal mass balance
is treated separately. Recently, in estimates of ice-sheet mass balance by modelling, the term has been extended to include internal accumulation. This extended meaning is discouraged. The unambiguous term climatic mass balance is recommended for the sum of the surface mass balance and the internal mass balance.
Refers to the roughness of a snow surface caused by precipitation or the wind as well as by uneven evaporation, sublimation, or melt. It does not refer to roughness due to snow microstructure.