The graves of 17th century Dutch whalers in Spitsbergen are in danger because global warming is melting the permafrost that has been protecting them, archaeologists have warned.

It is already too late for some of the graves, Maarten Loonen, researcher at Groningen university’s Arctic Centre told broadcaster NOS. ‘Since the 70s temperatures in Spitsbergen have gone up by 4 degrees and counting. The graves in the ice are beginning to rot.’

Spitsbergen, which was discovered by arctic explorer Willem Barentz in 1596, quickly became a hub for whalers, many of whom lost their lives there because of the arduous life at sea and rampant scurvy.

‘They were buried as deeply as possible, with stones on top to prevent polar bears and foxes from getting to them,’ Loonen said. During an expedition to Spitsbergen in 1979, researchers opened 50 of the graves.

The fully clothed skeletons they found provided valuable information, for instance about the type of clothing ordinary people were wearing at the time, Loonen said, but other, unexplored graves are in danger and may not give up their secrets.

‘The graves on the coast are being eroded very quickly and some of those we found were already empty with just some bones remaining.

‘Archaeologists are now faced with the dilemma of digging up the graves that are still protected by permafrost or simply leave them where they are.

‘Climate change is a very fast process and measures to combat it are very slow. So that is cause for pessimism. But it is also very complicated just to dig them all up because they are under threat,’ Loonen said.

‘On the other hand, it is a unique part of history which has been kept intact for a very long time and ‘we must try to preserve it.’