Geology Reference
In-Depth Information
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Figure 5.7.
Alpine permafrost. (A) Relationship between latitude and altitude of alpine perma-
frost in the Cordillera of North America. Points indicate localities where permafrost has either been
measured by ground temperatures or inferred from either local micro-climatic data or from geo-
morphic phenomena (ice-cemented rock glaciers, blockfi elds). From Péwé (1983a). (B) Altitude of
selected geographical boundaries plotted against latitude in the northern hemisphere. Line is visual
best fi t. From Cheng and Dramis (1992). Reproduced by permission of John Wiley & Sons Ltd.
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3 °C indicate that permafrost is “probable,” values of
−
2 °C to
−
3 °C that permafrost is
“possible,” and values of
2 °C that permafrost is “improbable.” However, these catego-
ries have not been quantifi ed. Thus, “probable” does not imply 100% likelihood of per-
mafrost and “improbable” does not mean 0% likelihood.
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