The Svalbard International Seed Vault (hereafter SISV), popularly referred to as the Norwegian "Doomsday Vault", is an ambitious project to provide an arctic back-up for the world's crops, guarding against both local disasters and more apocalyptic events devastating agriculture across the globe.
Agricultural efficiency tends to favour a highly restricted subset of crops that have optimal yields for given conditions. However, the danger is that crops which would be optimal for future conditions are driven to extinction as a result. For instance, the Global Crop Diversity Trust claims that of the 7100 named varieties of apple to be found in nineteenth-century America, less than 300 survive to this day.
Some 1400 gene banks around the world act to preserve this biodiversity through stockpiles of some 6.5 million samples, of which around 1-2 million are 'distinct'. The largest collections are generally found in the richest nations, but it is in the developing world where they are most needed and yet most vulnerable to war, civil strife or simple lack of funding. Gene banks serve as the cornerstone for breeding research, distributing several hundred thousand samples a year. However, SISV is not intended to be used in this way. Instead it will act as an insurance policy or archive for the existing seed banks, providing long-term storage to enable the recreation of a local bank should some disaster befall it.
To this end, Svalbard will be the largest seed bank by a considerable margin, with a capacity for three million samples (the US collection contains around 460,000 samples). Further, it is designed with the hope that it can protect against doomsday scenarios that might render all other seed banks useless- from nuclear war to severe global warming.
The Svalbard facility
The vault is to be constructed in Spitsbergen, part of the Svalbard archipelago about 600 miles from the North Pole. I say in since the design calls for the chambers to be located at the end of a 120 metre tunnel dug straight into a sandstone mountain. The tunnel and chambers will be reinforced with concrete, and sealed behind a pair of airlocks and blast-proof doors. Work began this year, with the hope of completion by September to allow an official opening in the winter of 2008.
The construction of SISV is being carried out (and financed) by the Norwegian government (Svalbard is part of Norway); but its operation is to be supported by the Global Crop Diversity Trust, which hopes to assist with the supply of seeds from developing countries. Technical expertise will be supplied by the existing Nordic Gene bank. Storage will be on a 'black box' basis, with gene banks sending samples responsible for testing and subsequent regeneration; stored samples will only be released if all other sources have been exhausted. The storage of Genetically-modified crops has not been ruled out, although they would be a tiny proportion of the collection.
Ideal storage for seeds is in the range of -10 to -20C; the Svalbard site was chosen for its permafrost which maintains a temperature of about -5C throughout the year. This ambient temperature and the very slow rate of warming given the depth of the vault should prevent thawing for decades. Global warming is unlikely to significantly alter the permafrost in the next 200 years, and the tunnel entrance, 130 metres above sea level, is secure against even the worst-case scenario of Antarctic meltdown. Whilst it is not expected that SISV would survive a direct nuclear strike, one would hope that Svalbard would be overlooked in a nuclear exchange.
Whilst Spitsbergen is undeniably remote and unforgiving (with a winter that sees temperatures of -18C and no sunrise for 4 months), the project is not attempting security through obscurity. Indeed, the site must be obvious and readily accessible to anyone who might have need of it. Thus the tunnel entrance is designed to "gleam like a gem in the midnight sun" during the summer, and will be illuminated during the winter. It is hoped that this conspicuousness will lead locals to report anything suspicious; there will also be video surveillance and remote monitoring of the vault status. The facility will not be permanently manned, but the crop trust dryly notes that "The presence of polar bears, which prowl the area, may be seen by some as providing an added layer of security".
Whilst the facility may be secure for decades if not centuries, the same need not necessarily apply to all its charges: frozen seeds eventually lose their ability to germinate, so samples must be periodically replaced by new seed. For some crops, such as peas, this is necessary every 20-30 years; others can survive for centuries- the record is believed to be about 2000 years, for a Judean date palm recovered from the palace of Herod the Great. Unfortunately, there are many species which cannot survive in a dormant state and thus are not suitable for freezing at all, such as cocoa. These can be continuously preserved by other gene banks, but could not be protected at SISV.
Actually getting to Spitsbergen to recover seeds is left as an exercise for the post-apocalyptic reader, should you find that the world's crops have failed.