What will it take to find Shackleton's lost Endurance ship

It's going to take a monumental effort to locate the iconic ship of Antarctic explorer Ernest Shackleton.

This is the conclusion of scientists who tried and failed last year to find the Endurance, which sank in 3,000m of water in the Weddell Sea in 1915.

The team says the sea-ice in the area above the wreck site is nearly always thick and extensive.

It means most expeditions would struggle even to get close enough to begin a search.

Prof Julian Dowdeswell, from the Scott Polar Research Institute, and colleagues have detailed their assessment of the issues involved in a new paper. The prof spoke with our science correspondent Jonathan Amos.