Antarctic ice loss increases to 200 billion tonnes a year

A major international study has found a tripling of ice loss in Antarctica over the past five years.

The rate of ice melting into the oceans is increasing at an alarming rate, according to a group of 84 scientists taken from 44 international organisations.

The scientists found that before 2012 ice was being lost at a steady rate of 76 billion tonnes, which contributed 0.2 mm to the rise in sea levels.

Since 2012, this has grown to 0.6mm representing an annual loss of 219 billion tonnes.

The international team, led by NASA, the University of Leeds and the European Space Agency, combined 24 satellite surveys between 1992 and 2017. They looked at the change in volume, flow and gravitational attraction across the entire Antarctic Ice Sheet. This huge 5.4 million square mile continent is roughly twice the size of Australia, and holds enough water to lift global sea levels by 58 metres.

Professor Andrew Shepherd at Leeds University said: “According to our analysis, there has been a step increase in ice losses from Antarctica during the past decade, and the continent is causing sea levels to rise faster today than at any time in the past 25 years. This has to be a concern for the governments we trust to protect our coastal cities and communities.”

“We have long suspected that changes in Earth’s climate will affect the polar ice sheets. Thanks to the satellites our space agencies have launched, we can now track their ice losses and global sea level contribution with confidence,” he added.

The new satellite measurements are now able to document glacier changes at higher levels of precision than ever before. This has allowed the scientists to provide one of the most complete pictures of how the continent is changing and contributing to the worldwide rises in sea level.

Dr Erik Ivins at NASA’s Jet Propulsion Laboratory, who co-led the study, commented: “The added duration of the observing period, the larger pool of participants, various refinements in our observing capability and an improved ability to assess both inherent and interpretive uncertainties, each contribute to making this the most robust study of ice mass balance of Antarctica to date.”