Scientists can see Earth’s permafrost thawing from space
Permafrost, which lies beneath about 15% of the land in the Northern Hemisphere, is defined as ground that has remained frozen for at least two years. Historically, much of the world’s permafrost has remained solid and stable for far longer, allowing people to build whole towns atop it. But as the planet warms, a process that is happening more rapidly near the poles than at more temperate latitudes, permafrost is thawing and causing a host of infrastructural and environmental problems. Now scie