Svalbard Global Seed Vault

Landmark in Longyearbyen

Deep inside a mountain, down beneath the permafrost, a vast artificial cavern, already dubbed the Doomsday Vault or a vegetarian Noah's Ark, was opened in 2008. It's a repository with a capacity for up to four million different seed types (and up to 2.25 billion seeds in all), representing the botanical diversity of the planet. Note that casual visitors are not welcome.

Samples (typically around 500 seeds kept in a sealed airtight aluminum bag) from seed banks and collections all over the world are kept here at a constant temperature of -18°C so that, should a species become extinct in its native habitat, it can be revived and won't be lost for eternity. The vault is built into the mountain above the airport, 130m above sea level to ensure the vault survives any future rise in sea levels. The Svalbard site was chosen due to its lack of tectonic activity and the preservative powers of its permafrost.

But in these days of climate change and temperature swings, even the best-laid plans sometimes need readjusting. In late 2016, unseasonably warm temperatures caused part of the surrounding permafrost to thaw and water flooded into the vault's entrance tunnel. The water then froze in the tunnel and never reached the seeds themselves – in that sense the tunnel's defence mechanism of freezing any entering water worked as it was designed to. But the fact that water was able to enter at all in a facility designed to last forever caused a rethink and the Norwegian government hurried to make improvements (such as waterproofing the entrance tunnel and digging drainage ditches around the vault) to prevent this from happening in the future.

As of early 2017, the vault was home to over 930,821 different seed varieties, with approximately 270 million individual seeds – it already holds the most diverse collection of food crop seeds on earth. Visit www.croptrust.org/our-work/svalbard-global-seed-vault for more information.

Plans were also announced in 2017 to build a 'data doomsday vault' in an adapted abandoned mine shaft on the same Svalbard hillside – the Arctic World Archive is a private venture designed to protect historically important documents and literature.