An anonymous reader quotes a report from The Guardian: It was designed as an impregnable deep-freeze to protect the world's most precious seeds from any global disaster and ensure humanity's food supply forever. But the Global Seed Vault, buried in a mountain deep inside the Arctic circle, has been breached after global warming produced extraordinary temperatures over the winter, sending meltwater gushing into the entrance tunnel. The vault is on the Norwegian island of Spitsbergen and contains almost a million packets of seeds, each a variety of an important food crop. When it was opened in 2008, the deep permafrost through which the vault was sunk was expected to provide "failsafe" protection against "the challenge of natural or man-made disasters". But soaring temperatures in the Arctic at the end of the world's hottest ever recorded year led to melting and heavy rain, when light snow should have been falling. "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. "A lot of water went into the start of the tunnel and then it froze to ice, so it was like a glacier when you went in," she told the Guardian. Fortunately, the meltwater did not reach the vault itself, the ice has been hacked out, and the precious seeds remain safe for now at the required storage temperature of -18C. But the breach has questioned the ability of the vault to survive as a lifeline for humanity if catastrophe strikes.