It may not be as dramatic as melting glaciers, but it could be more dangerous - Earth's permafrost is thawing. In the Arctic and Antarctic, most of the permafrost freezes over thousands of years, and its thickness can reach hundreds or even thousands of meters.
And if the soil thaws, that could mean bad news, because Earth's permafrost is not just composed of frozen soil. It also contains the remains of dead plants and animals that froze over before they could decompose. It can contain almost double the amount of carbon that is currently in the atmosphere - carbon that can be released as methane and carbon dioxide when the earth heats up. Scientists are using satellites to monitor Earth's permafrost.
“We cannot observe permafrost as such from space,” said Annette Bartsch. “But we can use many different types of satellite data, along with in situ measurements and simulations, to get a picture of what's going on.”
Satellite imagery and radar data show how the Earth's surface sinks and rises as the permafrost warms up. Thermal sensors offer information on surface temperatures.
The researchers gathered their findings from data collected between 2000 and 2016 to create a map of the permafrost. They shared their findings in Earth-Science Reviews.
As the melting permafrost causes landslides in the Arctic and even the coldest regions are threatened with warming, the Globe Permafrost group's research is becoming vital. The project is currently developing a permafrost information system that will help other researchers track the changing situation.
