permafrost
Link: http://w3id.org/permafrost/v/ipaglossary/t0244
Within: IPA Permafrost Glossary
Definition: Ground (soil or rock and included ice and organic material) that remains at or below 0°C for at least two consecutive years (see Figure 2).
| Term |
permafrost
en
pergélisol fr |
|---|---|
| Comment |
Permafrost is synonymous with perennially cryotic ground: it is defined on the basis of temperature. It is not necessarily frozen, because the freezing point of the included water may be depressed several degrees below 0°C; moisture in the form of water or ice may or may not be present. In other words, whereas all perennially frozen ground is permafrost, not all permafrost is perennially frozen. Permafrost should not be regarded as permanent, because natural or man-made changes in the climate or terrain may cause the temperature of the ground to rise above 0°C. Permafrost includes perennial ground ice, but not glacier ice or icings, or bodies of surface water with temperatures perennially below 0°C; it does include man-made perennially frozen ground around or below chilled pipelines, hockey arenas, etc. Russian usage requires the continuous existence of temperatures below 0°C for at least three years, and also the presence of at least some ice. (see pereletok).
en
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| dcterms:source |
https://doi.org/10.4224/20386561
xsd:anyURI
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| skos:altLabel |
perennially cryotic ground
en
perennially frozen ground en |
| skos:hiddenLabel |
permanently frozen ground
en
cryic layer en biennially frozen ground en climafrost en |