A measure of strength of the middle-latitude westerlies, usually expressed as the horizontal pressure difference between 35 and 55N latitude, or as the corresponding geostrophic wind.
A part of the glacier, and especially of the glacier surface, distinguished from other parts by the prominence or predominance of a particular mass-balance process. The temperate glacier of Figure 15
and the cold glacier of Figure 16 are end members of a continuum. Many glaciers have attributes, including patterns of zonation, that are intermediate between these end members. The conventional system of zones in the English-language literature diverges in part from that in Russian-language work (Shumskiy 1955). For the latter, which is based on the relative magnitudes of accumulation, melting and cold content.
Part of the water area contoured on an ice chart in the form of a closed polygon within which the ice cover characteristics given for this zone are considered similar. A zone can be sub-divided into a
basic zone and additional zones.