ScienceJuly 15, 2026
permafrost
/ˈpɜːrməfrɔːst/
Definition
Ground, including rock or soil, that remains at or below zero degrees Celsius for at least two consecutive years, often containing trapped greenhouse gases.
Etymology
The term is a portmanteau of the words 'permanent' and 'frost,' coined in the mid-20th century to describe ground that stays frozen year-round.
In the news
In this article, permafrost thaw is identified as an Earth-system feedback that could release trapped carbon, thereby reducing the global carbon budget available for human emissions. It is cited as a factor that makes current climate projections more conservative and urgent.
Scientific uncertainty in forward-looking climate change litigation
Read the full article ↗The London School of Economics and Political Science