Arctic doomsday vault - stronghold of the world's seed supply - floods after permafrost melts
Part of the Arctic stronghold of the world's seed supply has been flooded by melting permafrost - something scientists never envisaged happening.
The Global Seed Vault is buried in a mountain deep in the Arctic circle. It is a secure facility on the rugged Arctic Svalbard archipelago between mainland Norway and the North Pole. It houses a million packets of world's most precious seeds in an impregnable chamber - a lifeline for humanity if a catastrophic event hits Earth.
Opened in 2008, the vault, on the Norwegian island of Spitsbergen, was meant to be able to survive any event humanity could throw at it. But 2016 threw a curveball - the hottest ever recorded year, with average temperatures 7 degrees Celsius above normal on the island.
Melting permafrost and heavy rain - which fell instead of the usual light snow - led to water seeping into the vault's entrance, The Guardian reported. While it didn't reach the area where the seeds were stored, it has raised concerns about the vault's ability to operate as designed.
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"It was not in our plans to think that the permafrost would not be there and that it would experience extreme weather like that," said Hege Njaa Aschim, from the Norwegian government, which owns the vault.
Aschim told The Guardian the water ran into the start of the vault's tunnel, then froze - "it was like a glacier when you went in".
The ice has been chipped out, but Aschim said the vault was now being monitored 24 hours a day.
"We must see what we can do to minimise all the risks and make sure the seed bank can take care of itself," she told The Guardian.
Managers of the vault were now launching into major work to protect the vault, including waterproofing the 100m-long tunnel that runs into the mountain and digging trenches to carry meltwater and rain away from it.
The vault holds a growing collection of New Zealand seeds, protecting the country's agriculture industry from loss of plant species if war, disease or disaster strikes.
In early May, AgResearch sent the seeds via an air mailed package to the vault.
It was the second delivery of its kind from AgResearch's Margot Forde Germplasm Centre (MFGC), following an agreement made last year.
The MFGC in Palmerston North is home to thousands of species including forages used to farm livestock in New Zealand - some developed for specific traits and environments - as well as herbs, legumes and endangered plant species.
This year, about 500 packets of seeds covering about 40 species of plants were sent to vault. A similar deposit was made last year.