Cryosphere glossary
an area of ocean that extends from the permanent ice zone to the boundary where winter sea ice extent is at a maximum; here, sea ice is present only part of the year; this zone primarily consists of first-year ice.
the cumulative number of degree-days above 0 degrees Celsius, calculated as the arithmetic sum of all the positive and negative mean daily air temperatures (degrees Celsius) for a specific station during the time period between the lowest point in the spring and the highest point the next fall on the cumulative degree-day time curve.
the uppermost layer of the permafrost which undergoes seasonal phase changes due to the lowered thawing temperature and freezing-point depression of its pore water.
sea ice which has not melted in the first summer of its existence; by the end of the second winter, it attains a thickness of 2 meters (6.6 feet) or more; it stands higher out of the water than first-year ice; summer melting has somewhat smoothed and rounded the hummocks, which accentuation of minor relief by differential melting may have caused others to develop; bare patches and puddles are usually greenish-blue.
alternating bands of light and dark at the firn limit of a glacier; the light bands are usually young and lightest at the highest level up-glacier, becoming increasingly older and darker as they progress down-glacier.
the ratio of the rate of moisture migration to the temperature gradient in a frozen soil near the 0 degrees Celsius isotherm.
high pressure area largely predominate during a major portion of the year where an anticyclone appears on the mean monthly pressure charts.
same as enthalpy; the heat absorbed or transmitted by a substance during a change of temperature which is not accompanied by a change of state; used in meteorology in contrast to latent heat.
a polynya that forms from the upwelling of warm (above-freezing) ocean water from lower depths; these can form in mid-ocean areas, far from coasts or other barriers.
in geology, describes the compressive strength (ability to withstand pushing forces) of soils; results from two internal mechanisms: cohesion between soil particles, and friction caused by contact between particles; variable among different soils.
a screen to shield a rain-gauge from the influence of the wind, or to shield a thermometer against insolation.