Permafrost Tunnel and Super-Site

Permafrost, ground that is continually below 0C for two or more years, is a notable feature of the Arctic. The CRREL Permafrost Tunnel (drilled into a hillside) is a virtual time machine where ancient vegetation and fossils from long extinct animals can be easily seen entombed in the frozen ground. Ice wedges with an age of over a hundred thousand years are another amazing feature to be seen.

Many meters underground Misha K (with the flashlight) explains permafrost formation processes. We can see both the main tunnel and the offshoot tunnel (with yellow walkway)

Hands-on experience (literally) with vegetation entrapped in permafrost that is well over 10,000 years old

After being in the sub-freezing temperatures of the permafrost tunnel, everyone was ready for some sun at lunchtime

Next stop for the day was the Super-Site flux tower which has been operated by IARC for over five years. This tower measures the energy, mass and carbon balance of a Black Spruce forest and aims to distinguish how much the upper canopy and understory vegetation each contribute to various fluxes.

The Super-Site Flux Tower has various instruments all the way up the tower

Guo explains the instrumental set-up at the tower and answers questions about observational methods

Vladimir, Marc and Sophia observing and probing the very wet and thick moss layer

Mmm ... tasty blueberries direct from the Alaskan forest

Andrea, Danica and Charles return from the forest with a bounty of blueberries

A final stop was made at a section of the Trans-Alaska Pipeline System. This engineering feat transports oil all the way from the Arctic Ocean, across a full North-South transect of Alaska, to the port of Valdez on the Pacific Ocean.

The pipeline. The vertical silver items are cooling fins that form part of a thermosiphon (a device for keeping the adjacent ground cool so that permafrost does not thaw and damage the pipeline).