Climate change is threatening the “doomsday vault” that holds emergency copies of the world’s crop seeds, CNN reported.

The vault is located just outside Longyearbyen, the world’s northernmost town, located on an island in Norway’s Svalbard archipelago. It contains nearly 1 million packets of seeds with origins in nearly every country.

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Longyearbyen was selected as the vault’s location because Norway has an “extremely stable” political system and the region is not vulnerable to natural disasters like earthquakes or volcanoes, Maria Haga, executive director of the Crop Trust, which built the vault in 2008, told CNN.

But recently, climate change issues may threaten the conditions that made the town ideal more than a decade ago. For example, while permafrost disturbed by construction work typically refreezes, the ground against the entrance tunnel for the vault has yet to refreeze, Haga told CNN, and in October 2016 heavy rainfall flooded half the tunnel floor.

In response to these red flags, Statsbygg, the Norwegian government agency responsible for construction, undertook another $11.7 million in construction work, replacing the steel entrance tunnel with one made of waterproof concrete and moved electrical equipment from inside the tunnel to a separate building, as well as digging ditches for meltwater.

The agency also threaded pipes containing coolant through the soil and put a freezing mat on top of the tunnel to keep the permafrost frozen, according to CNN.