Permafrost Underlies 15% of the Northern Hemisphere’s Land Surface

Journal of Geophysical Research: Earth’s Surface, April 23

More than 80% of studies reporting on permafrost area overestimate the baseline extent of permafrost underneath Earth’s surface, claiming that permafrost underlies a quarter (22%) of the Northern Hemisphere. Such overstatements give the impression that there is 6 million km2 more permafrost than currently estimated. In reality, permafrost exists in different continuous, discontinuous, sporadic, and isolated zones, which combined represent the permafrost region. However, these zones are not entirely underlain by permafrost – the actual permafrost area reaches only approximately 14 million km2, which is equal to 15% of the exposed land surface area in the Northern Hemisphere. Authors warn that this confusion between the terms “permafrost region” and “permafrost area” often results in an overestimation of permafrost extent; and muddies discourse within the geoscientific community and the general public at large.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2021JF006123