Defences of 'doomsday' seed vault tightened after breach

Svalbard Global Seed Vault (Reuters)
It's supposed to withstand all natural and man-made disasters, but it's been threatened by climate change (Reuters / file)

The seed vault built to withstand anything thrown at it, from natural to man-made disasters, has been breached - by climate change.

The Svalbard Global Seed Vault holds almost a million packets of seeds to preserve the world's food crops in case of a global disaster, calling itself "the final back-up".

It's buried inside a mountain, deep within the Arctic circle, sunk into a thick layer of permafrost.

But now it's been threatened by climate change - the permafrost, which was supposed to protect the vault, has been melting.

"It was not in our plans to think that the permafrost would not be there and that it would experience extreme weather like that," Hege Njaa Aschim, from the Norwegian government, told The Guardian.

Temperatures in the Arctic have been soaring; last year, NOAA found parts were an average 11degC warmer than in the late 20th century.

The warmer temperatures have caused heavy rain, melting the permafrost.

Water flooded into the tunnel's entrance before freezing. It didn't reach the seeds, which are stored further down and at -18degC.

But it was enough to send Norway's government, which owns the vault, racing into action.

"Statsbygg is now implementing measures that will continue to protect the seed vault in the future," The Crop Trust, which runs the vault in partnership with Norway's government, said in a statement.

They're now digging drainage ditches, removing heat sources near the tunnel's entrance, and installing a new waterproof wall to help stop further leakages.

Pumps are also in place in the outer part of the vault, which immediately pump out water that makes it in.

The trust says even though there was a breach, the new measures are being brought in on a "better safe than sorry" approach.

"The effect of the measures will be continuously assessed in the coming years," the trust says.

"If they are not sufficient, further and more extensive measures will be implemented."