Global Seed Vault. Photo: Line Reeh

Artificial cooling of Arctic soil safeguards global genetic material

Geology
Artificial cooling and creative engineering solutions are key to taking good care of the backup copies of the world’s plant-based genetic material, which are stored in the permafrost on Svalbard.

Behind the solid metal swing doors with large padlocks and buried in the Arctic permafrost on Svalbard hides a frozen seed storage. The name of the seed storage is Svalbard Global Seed Vault, and it acts as a backup copy of plant-based genetic material from all over the world.

In the event that the seeds in the national or regional gene banks—which can be found around the world—are destroyed due to e.g. natural disasters or an acute lack of resources, a spare copy can be retrieved from the seed bank near Longyearbyen on Svalbard.

Leaking steel tunnel in permafrost needed to be replaced

Tim Hoff-Lund Sørensen, student at Arctic Technology, is one of the few people who have access to the innermost halls of the seed bank. For safety reasons, these halls are not open to visitors. He works for the Norwegian company Geofrost A/S, which performs engineering work in connection with the cooling of the seed bank.

The seeds on Svalbard are cooled to prolong their life. A constant temperature of minus 18 degrees Celsius results in the desired lifetime. It is therefore essential to find a long-term solution to keep seeds refrigerated, even in the event of a power failure.

Although the seed bank was constructed in permafrost—which is soil that has been in a permanently frozen state for more than two years—this temperature is not low enough to keep the seeds sufficiently cooled, as the permafrost in the area is only about minus 2-3 degrees Celsius. To lower the temperature further, it has been necessary to install cooling devices that can contribute to a permanent cooling throughout the seed bank’s entire tunnel system.

Tim Hoff-Lund has worked for Geofrost since May 2018. One of his first and biggest tasks was to help build a new concrete tunnel to replace the original steel tunnel, which was installed in the seed bank in 2008. Here they worked with cooling as well, as Geofrost made use of freezing to define the construction pit while the earth around the tunnel was dug away.

"Greenland and Svalbard have much in common in the sense that there are very limited resources available. You therefore learn to be resourceful about the things you do have. "
Tim Hoff-Lund Sørensen, Arctic Technology student

Artificial cooling of the soil was not used when the original steel tunnel was constructed, and this was part of the reason why conditions weren’t optimal, explains Tim Hoff-Lund Sørensen.

“After the tunnel excavation, they put the soil back into the hole to cover the tunnel without taking the soil’s temperature into account. This meant that you had a structure that was designed to be buried in the permafrost, but was instead surrounded by a large mass of earth which wasn’t frozen. One day it rained heavily, and the steel tunnel wasn’t able to keep out the water. Fortunately, the water collected in a security pocket and did not reach the cooled seeds,” says Tim Hoff-Lund Sørensen.

The combination of unfrozen soil and a tunnel that had been designed to be buried in permafrost meant that the soil was permeable to water, which leached the soil over time. It took several rounds of rain to develop the problem of flooding, and after a particularly violent rainstorm a decision was made to solve the problem by renovating the tunnel.

Engineering skills were quickly put to the test

Tim Hoff-Lund Sørensen has followed the construction of the new tunnel closely from his work site on Svalbard, first as an intern and then as a part-time Project Engineer for Geofrost. As an intern, his engineering skills were quickly put to the test.

After about a month of employment, Tim Hoff-Lund Sørensen was the only employee from Geofrost present on Svalbard. Only two days after his superior had left, Tim Hoff-Lund Sørensen discovered a leak on his daily round. He called his boss, and they agreed on a method that he began completely on his own. The entire task took him approx. 14 hours with minimal breaks.

A little while later in the internship, Tim Hoff-Lund Sørensen again faced a challenge on the construction site. He was short of 40 metres of hose, which needed to be connected to a compressor at the bottom of a hill. He had borrowed hoses elsewhere on the site, but they turned out to be incompatible when he attempted to connect them.

“I didn’t have the resources to procure new hoses, and it would have been quite costly and taken a long time to get a hold of them, even if I did. So I was racking my brain on how I could get the hoses to fit together,” recalls Tim Hoff-Lund Sørensen.

The solution was to connect the hoses with small rubber diaphragms and squeeze them together with a type of nut called a hose clamp.

“With the help of a good screwdriver, a little commitment and a little patience I got all these hoses connected, all the way to the top. And I got the pressure I needed in them,” says Tim Hoff-Lund Sørensen.

In both situations, Tim Hoff-Lund Sørensen was pleased with the experience his studies in Arctic Technology and his stay in Sisimiut in Greenland had given him.

“Greenland and Svalbard have much in common in the sense that there are very limited resources available. You therefore learn to be resourceful about the things you do have. We know how to solve problems somewhat creatively—I have often made use of materials and resources in non-traditional ways. This makes it possible to achieve the results you want, even when you don't have what you actually need,” says Tim Hoff-Lund Sørensen.

Internship provided inspiration for a mobile lab in Greenland

Thomas Ingeman-Nielsen is an associate professor at DTU Civil Engineering and does research on permafrost. He was the internship supervisor for Tim Hoff-Lund-Sørensen when he worked in the seed bank in Svalbard as part of his internship.

“Internships give the students an opportunity to try their skills on real life issues. In Tim’s case, he even had the opportunity to work on a unique project where his skills as an engineer with Arctic Technology as his area of specialization really came into play. It has been incredibly exciting to follow the project from a supervisor point of view,” says Thomas Ingeman-Nielsen.

Even though Thomas Ingeman-Nielsen mostly stayed on the sidelines, he was still inspired by, among other things, a mobile geotechnical laboratory, which Tim Hoff-Lund Sørensen played a part in constructing with Geofrost. The idea of the laboratory is that it is extremely easy to move, because it is built into a container with standard dimensions. This means that it is easy to transport by ship. Thomas Ingeman-Nielsen imagines that a similar mobile laboratory could be of great use in Greenland, where the majority of his research takes place.

“A fully-equipped mobile laboratory would be a fantastic addition to the field work in Greenland. It would mean that we can analyse our permafrost samples on site and thus avoid transporting them all the way to the lab in Lyngby at the risk of exposing the samples to temperature damage along the way. I see great potential in mobile laboratories for field work in remote areas,” says Thomas Ingeman-Nielsen.

What is the Svalbard Global Seed Vault?

The Svalbard Global Seed Vault has been constructed as a safety storage for seeds from all over the world. The purpose is to have backup copies of the world’s crops that can then be restored in the event of natural disasters or an acute lack of resources.

The seed bank opened in 2008 and has been built into the permafrost in a bedrock near the town of Longyearbyen on Spitsbergen Island in the Svalbard Archipelago.

The Svalbard Global Seed Vault has room for 4.5 million seed samples. This is twice as many as the number of seed samples assumed to be stored in all the gene storages in the world today, which means that the seed bank has the capacity to receive new seeds for a long time to come.