Analysis of boulders deposited by glaciers in Antarctica has shown that the rate at which the icecap is melting has increased dramatically in recent years, according to research published in the journal Geology.

A team of glaciologists led by Joanne Johnson of the British Antarctic Survey (below), collected boulders that had been carried by three glaciers into the Amundsen Sea Embayment and analysed their isotope records to establish how long they had been exposed to the elements.

Their initial findings suggest that Pine Island Glacier has thinned by around four centimetres per year over the past 5,000 years, while Smith and Pope glaciers thinned by just over two centimetres per year during the past 14,500 years – dramatically slower than the rate of around 1.6 metres per year recorded on Pine Island Glacier since the 1990s.