What is Permafrost?
[[File:Circum-Arctic Map of Permafrost and Ground Ice Conditions.png|thumb|right|250px|Map showing the extent and types of permafrost in the [[Northern Hemisphere]].]] [[File:Digging in permafrost.jpg|thumb|right|250px|Two men dig in [[Alaska]] to study soil. A [[jackhammer]] is used to break the hard permafrost]] In [[geology]], '''permafrost''' is [[soil]] that stays frozen all year. To be called permafrost, soil must stay at or below {{convert|0|C}} for two or more years. Permafrost is also called '''cryotic soil'''. Most permafrost is on land close to the [[North Pole|North]] and [[South Pole|South]] poles. Other permafrost is found in high mountain areas. <ref>{{cite journal|last=Schuur|first=Ted |authorlink= |title=Thawing Permafrost Would Accelerate Global Warming. Thawing Arctic tundra will likely speed up climate change for a century or more. The question is: How drastically?|journal=[[Scientific American]]|year=2016 |volume=315 |issue=December 2016|pages=56–61|doi=10.1038/scientificamerican1216-56 |pmid=28004690 |url=https://www.scientificamerican.com/article/thawing-permafrost-would-accelerate-global-warming|accessdate=25 November 2016}}</ref> When permafrost melts, [[carbon dioxide]] is released which can be bad for the environment. ==References== {{Reflist}} ==Other websites== {{Commons category|Permafrost}} [[Category:Soil]] {{science-stub}}