Editing Permafrost (section)

==== Continuous permafrost ====
{| class="wikitable floatright"
|+ Estimated extent of alpine permafrost by region<ref name="BockhMunr" />
|-
! Locality
! Area<br />
|-
| [[Qinghai-Tibet Plateau]]
| style="text-align:right;" | {{convert|1300000|km2|mi2|abbr=on}}
|-
| [[Khangai Mountains|Khangai]]-[[Altai Mountains]]
| style="text-align:right;" | {{convert|1000000|km2|mi2|abbr=on}}
|-
| [[Brooks Range]]
| style="text-align:right;" | {{convert|263000|km2|mi2|abbr=on}}
|-
| [[Siberia#Mountain ranges|Siberian Mountains]]
| style="text-align:right;" | {{convert|255000|km2|mi2|abbr=on}}
|-
| [[Greenland]]
| style="text-align:right;" | {{convert|251000|km2|mi2|abbr=on}}
|-
| [[Ural Mountains]]
| style="text-align:right;" | {{convert|125000|km2|mi2|abbr=on}}
|-
| [[Andes]]
| style="text-align:right;" | {{convert|100000|km2|mi2|abbr=on}}
|-
| [[Rocky Mountains]] (US and Canada)
| style="text-align:right;" | {{convert|100000|km2|mi2|abbr=on}}
|-
| [[Alps]]
| style="text-align:right;" | {{convert|80000|km2|mi2|abbr=on}}
|-
| [[Fennoscandian]] mountains
| style="text-align:right;" | {{convert|75000|km2|mi2|abbr=on}}
|-
| Remaining
| style="text-align:right;" | <{{convert|50000|km2|mi2|abbr=on}}
|}
At mean annual soil surface temperatures below {{convert|-5|C}} the influence of aspect can never be sufficient to thaw permafrost and a zone of continuous permafrost (abbreviated to '''CPZ''') forms. A line of continuous permafrost in the [[Northern Hemisphere]]<ref>{{cite book |title=Frozen ground engineering |first1=Orlando B. |last1=Andersland |first2=Branko |last2=Ladanyi |publisher=Wiley |year=2004 |page=5 |isbn=978-0-471-61549-1 |edition=2nd}}</ref> represents the most southern border where land is covered by continuous permafrost or glacial ice. The line of continuous permafrost varies around the world northward or southward due to regional climatic changes. In the [[southern hemisphere]], most of the equivalent line would fall within the [[Southern Ocean]] if there were land there. Most of the [[Antarctica|Antarctic continent]] is overlain by glaciers, under which much of the terrain is subject to basal [[pressure melting point|melting]].<ref>{{Cite journal |last=Zoltikov |first=I. A. |title=Heat regime of the central Antarctic glacier |journal=Antarctica, Reports of the Commission, 1961 |pages=27–40 |year=1962 |language=ru }}</ref> The exposed land of Antarctica is substantially underlain with permafrost,<ref>{{Cite book |first1=Iain B. |last1=Campbell |first2=Graeme G. C. |last2=Claridge |editor-last=Margesin |editor-first=Rosa |contribution=Antarctic Permafrost Soils |isbn=978-3-540-69370-3  |title = Permafrost Soils |volume=16 |year=2009 |pages=17–31 |place = Berlin |publisher=Springer |doi=10.1007/978-3-540-69371-0_2 |series=Soil Biology }}</ref> some of which is subject to warming and thawing along the coastline.<ref>{{Cite news |last=Heinrich |first=Holly |title=Permafrost Melting Faster Than Expected in Antarctica |publisher=[[National Public Radio]] |date=25 July 2013 |url=https://stateimpact.npr.org/texas/2013/07/25/permafrost-melting-faster-than-expected-in-antarctica/ |access-date=23 April 2016 |archive-url=https://web.archive.org/web/20160503120018/https://stateimpact.npr.org/texas/2013/07/25/permafrost-melting-faster-than-expected-in-antarctica/ |archive-date=3 May 2016 |url-status=live }}</ref>