Permafrost

global temperatures

As ________ rise, permafrost is thawing, releasing trapped carbon dioxide and methane, which can contribute to further warming.

Permafrost

________ in the critical zone plays an important role in controlling the exchange of water, nutrients, and energy between the atmosphere, vegetation, and subsurface.

Permafrost

________ is a layer of soil that remains at or below 0°C for at least two consecutive years.

Permafrost

________ acts as a barrier, preventing the exchange of water, nutrients, and energy between the atmosphere, vegetation, and subsurface.

Permafrost

________ can also provide insight into the presence and movement of groundwater, the formation of landscapes and geologic features, and the distribution of minerals and other resources.

Permafrost

________ can provide important information about past and present environmental conditions, as well as potential future changes.

Ground temperature monitoring

The temperature of the soil is monitored to determine if it is above or below 0°C, the temperature at which permafrost is defined as thawed

Borehole temperature logging

A thermistor or other temperature sensor is lowered into a borehole to measure the temperature of the permafrost at different depths

Ground Penetrating Radar (GPR)

GPR can be used to determine the depth and thickness of permafrost layers by sending electromagnetic waves into the ground and measuring the reflection of these waves

Permafrost Cores

Permafrost cores can be extracted using a drill, and the samples can then be analyzed to determine the composition, age, and other characteristics of the permafrost

Active layer monitoring

The active layer is the top layer of soil that thaws and freezes each year, and can be used to indirectly measure permafrost conditions