Collapse of Antarctic glacier the size of Britain threatens to flood coastal towns

An Antarctic glacier the size of Britain is threatening to submerge UK coastal towns by collapsing into the ocean and raising sea levels, scientists fear.

British and American experts are launching the largest joint mission for more than 70 years to investigate how long the 113,000 square-mile Thwaites Glacier can last in its current form.

A fleet of research ships, submarines and aircraft and more than 80 scientists will be dispatched to the remote west Antarctic region later this year following warnings the ice structure could collapse within decades.

Glaciologists predict the collapse of both Thwaites and the nearby Pine Island Glacier, two of the largest and fastest retreating on the continent, could cause sea levels to rise by over one metre.

However, this could then trigger the collapse of the entire West Antarctic Ice Sheet, meaning ocean rises of more than three metres.

Climate models have indicated that a 1-metre rise would significantly increase the frequency of devastating storm surges, such as hit UK eastern coastal towns in 2013.

But a rise of two or more metres may cause permanent changes to the British coast line, with settlements such as Hull, Peterborough, Portsmouth and parts of East London and the Thames Estuary at threat of becoming submerged.

Yesterday leaders of the project, which comprises the the UK’s Natural Environment Research and the US National Science Foundation (NSF), said there were “reasons to suspect” that a Thwaites ice retreat, once started, would be irreversible.

Scott Borg, NSF Deputy Assistant Director for Geosciences, said: “What happens in the Antarctic doesn’t stay in the Antarctic.

“Thwaites has the potential to affect sea levels worldwide.

“Humanity cannot afford to wait.”

The five-year will project, which will comprise eight distinct research objectives, will be one of the biggest Antarctic field missions ever launched.

At nearly 1,000 miles from the nearest permanent base, the glacier is one of the most challenging environments on the continent.

The team will need to move more than 200 tonnes of scientific equipment into place in order to probe the stability of the ice.

They will use unmanned submarines to examine the underside of the glacier including, in the latter stages, the Autosub Long Range-class Boaty McBoatface.

They will also enlist the help of seals, which will be fitted with head-worn sensors.

David Vaughan, Director of Science at the British Antarctic Survey, said: “We’re going to be pushing the field season to the limit of the time you can spend in Antarctica to make the most of the opportunity.”

Sea levels are currently rising by 3.2 mm a year and some scientists believe that, at a conservative estimate, oceans may have risen by approximately 30 cm by 2100 compared to 2000.

However, others predict that, mainly due to climate change, the world should brace for rises of 1.5 or even 2 metres.

“It’s not an emergency this year, but I’m very pleased we’re doing it [the project] this decade because we can’t wait too long,” said Professor Vaughan.

Colleagues said yesterday Thwaites Glacier, which cuts deeply into the West Antarctic ice shelf, was already showing signs of instability.

Around 50 billion tonnes of ice is already draining into the ocean, accounting for around four per cent of global sea level rise, an amount that has doubled since the mid 1990s.

One of the scenarios the team will be investigating is the “rapid runaway calving” tall ice cliffs at the edge of the glacier, similar to what has taken place in Greenland.

Thwaites Glacier was first reached by researchers in 1957, but interest in the region soon waned due to the logistical challenges it posed.

Sam Gyimah, Science Minister, said: “Rising sea levels are a globally important issue which cannot be tackled by one country alone.

“The Thwaites Glacier already contributes to rising sea levels and understanding its likely collapse in the coming century is vitally important.”