In as little as 25 years, ocean melting has caused ice thinning to spread across West Antarctica so rapidly that nearly a quarter of its glacier is now affected, a new research study from the University of Leeds has found.
By compiling 25 years of satellite observations, the team from the UK’s Centre for Polar Observation and Modelling (CPOM) has found that Antarctica’s ice sheet has thinned by up to 122 metres in places, with the most rapid changes occurring in West Antarctica where ocean melting has triggered glacier imbalance.
“We can see clearly now that a wave of thinning has spread rapidly across some of Antarctica’s most vulnerable glaciers, and their losses are driving up sea levels around the planet,” Professor Andrew Shepherd, CPOM’s director said.
This means that the affected glaciers are unstable as they are losing more mass through melting and iceberg calving than they are gaining through snowfall.
The team found that the pattern of glacier thinning has not been static.
Since 1992, the thinning has spread across 24% of West Antarctica and over the majority of its largest ice streams - the Pine Island and Thwaites Glaciers - which are now losing ice five times faster than they were at the start of the survey.
Professor Shepherd added: “Knowing how much snow has fallen has really helped us to detect the underlying change in glacier ice within the satellite record.
"We can see clearly now that a wave of thinning has spread rapidly across some of Antarctica’s most vulnerable glaciers, and their losses are driving up sea levels around the planet.
“Altogether, ice losses from East and West Antarctica have contributed 4.6 mm to global sea level rise since 1992.”