Experts predict two possible futures for Antarctica after massive ice loss

14 Jun 2018

Image: Smallcreative/Shutterstock

The latest figures on Antarctic ice loss have left many people shocked, with scientists suggesting two possible futures for the continent.

It seems as if bad news about our climate has been unrelenting over the past few years, and this has only continued after a new paper published to Nature used satellites to reveal the full extent of ice loss on the continent of Antarctica.

The team of scientists found that as much as 200bn tonnes of ice is being lost every year into the world’s oceans, pushing planet-wide sea levels up by 0.6mm annually.

This is a threefold increase since the last assessment was taken in 2012, and the losses are predominantly found in the western half of the continent.

It is estimated that since 1992, when detailed satellite observations of the continent began, more than 2.7trn tonnes of ice has been lost, pushing up global sea levels by 7.5mm.

These findings are no doubt alarming, and another paper also published in Nature, unconnected with this research, has attempted to predict our planet’s future in the face of such a staggering ice loss, coming to the conclusion that there are only two likelihoods.

The team of nine authors – experts in biology, oceanography, glaciology, geophysics, climate science and policy – said that while “highly speculative”, its research delves into the long-term consequences of decisions made today for such variables as ice shelves, invasive species, sea ice, ocean and land ecosystems, mining, and other human uses.

Need for ‘ambitious action’

The first scenario would see humans continue to pump out greenhouse gas emissions unchecked, with policy responses proving ineffective, resulting in a climate that continues to warm, with worldwide impacts.

Antarctica and the Southern Ocean would see a dramatic loss of major ice shelves by 2070, leading to increased loss of grounded ice from the Antarctic ice sheet and a rise in global sea levels, the team said.

The second scenario, meanwhile, would show the results of “ambitious action” taken to limit greenhouse gas emissions and to establish policies that reduce human pressure on the environment, slowing the rate of change and enhancing Antarctica’s resilience.

This, the authors believe, might allow the continent in 2070 to look “much like it did in the early decades of the century”, with ice shelves intact, slower loss from the ice sheet and reduced threat of sea levels rising.

Lead author of the paper, Steve Rintoul, said: “The trajectory that will play out over the next 50 years depends on choices made today.

“Greenhouse gas emissions must start decreasing in the coming decade to have a realistic prospect of following the low-emissions narrative and so avoid global impacts associated with change in Antarctica, such as substantial sea level rise.”

Colm Gorey was a senior journalist with Silicon Republic