A freezer at the top of the world
Deep inside Platåberget, or "Plateau Mountain," on the Norwegian island of Spitsbergen is a facility designed to be the ultimate insurance policy for the world's food supply. The Svalbard Global Seed Vault is buried 120 meters into the sandstone mountain, a location chosen for its tectonic stability and the preserving qualities of its natural permafrost. The vault consists of three separate storage halls, each about 27 meters long, with a combined capacity to store 4.5 million distinct crop varieties. Each sample is a package of about 500 seeds, meaning the vault can hold a maximum of 2.25 billion seeds.
The purpose of the vault is to be a secure backup for the more than 1,700 agricultural genebanks around the globe. These national and regional banks store crop diversity but are vulnerable to wars, natural disasters, or even simple equipment failures. The seeds in Svalbard—sealed in three-ply foil packages at a temperature of -18°C—are kept under "black box" conditions. The depositing institution retains ownership and is the only entity that can withdraw them. As of May 2024, the vault holds over 1.3 million seed varieties from nearly every country. The permafrost, which naturally maintains a temperature between -3°C and -4°C, was intended to keep the seeds frozen even if the facility's powered cooling systems failed.
When the permafrost failed
The vault's design relied on the stability of the Arctic environment. In late 2016 and early 2017, however, record-high Arctic temperatures caused extensive melting of the surrounding permafrost. Water from the melt and unusually heavy rains seeped into the 100-meter-long access tunnel. The water did not reach the three main seed storage chambers, which are located deeper inside the mountain. Instead, the water froze in the outer section of the tunnel, forming a glacier-like block of ice that had to be manually hacked out by workers. No seeds were ever damaged or at risk.
The event showed that the "failsafe" design was vulnerable to the very climate change it was meant to outlast. The permafrost had not re-frozen and established itself around the entrance tunnel as originally planned after construction. In response, the Norwegian government funded a major upgrade costing over 100 million Norwegian Krone (more than $10 million USD). The improvements included waterproofing the access tunnel, digging drainage ditches into the mountainside to channel water away, and moving heat-producing electrical equipment out of the tunnel. A new concrete access tunnel and a service building to house refrigerating units were also constructed.