Antarctic ice is melting faster than ever: scientists


The study looked at the "mass balance of the Antarctica Ice Sheet between 1992 and 2017", and found that during that time the continent lost three trillion tons of ice and raised sea levels three-tenths of an inch, according to the New York Times.

Between 2012 and 2017 the continent lost 219 billion tonnes of ice per year - a 0.6mm per year sea level contribution.

Shepherd says that actually, their data shows a "a progressive increase in ice loss throughout the whole 25 year time period".

The only period when the quantity of ice lost dropped was between 1997 and 2002, when Antarctica saw a loss of 38 billion tonnes per year compared to 49 billion per year for the five years prior to that period.

"With the number of scientific studies focusing on this region, the technological tools we have at our disposal and data sets spanning several decades, we have an unequivocal picture of what's happening in Antarctica", Eric Rignot, an Earth system science professor at the University of California Irvine who participated in the research, said in a statement.

Scientists have acknowledged that these sad results surpassed their expectations.

"That's a big jump, and it did catch us all by surprise", Shepherd says.

While the western Antarctica ice sheet has been steadily melting, there has been evidence that East Antarctica itself was stable, or even growing. The melting is happening so fast that it could cause sea levels to rise 6 inches by the end of the century, the study projects. Ice shelf collapse in the Antarctic Peninsula is another major contributor, whereas less certain estimates of East Antarctica's mass change suggest the region may have gained a negligible amount of ice. Seas also rise from melting land glaciers elsewhere, Greenland's dwindling ice sheet and the fact that warmer water expands.

For the new study, the scientists combined data from three types of satellite measurements to track changes in ice over time, study co-author Andrew Shepherd, a professor of Earth observation with the School of Earth and Environment at the University of Leeds in the United Kingdom, told Live Science. The increases are on the order of a few millimetres per year, but scientists need to account for them to ensure their other measures of ice loss are accurate.

"We have long suspected that changes in Earth's climate will affect the polar ice sheets", Shepherd explained in a statement published by Leeds.

Regardless of the exact rate, these findings emphasize the importance of efforts to combat climate change. The rate at which ice losses from Antarctica will increase in response to a warming world remains uncertain.

"We're still talking about roughly a half a millimeter per year, " DeConto said.

Those signs help researchers to gauge the pace of ice retreat in Antarctica - estimated in the past to be about 164 feet (50 meters) each year - between glacial cycles, Shepherd said.

Watch below to see where the Antarctic ice sheet has been suffering its greatest losses over the past 25 years.

It can be easy to overlook the monstrous scale of the Antarctic ice sheet. This agrees with the latest climate models, which predict that variations in Antarctic ice volumes are driven mostly by the melting of sea ice.

The Antarctic ice sheets are melting many times faster than previously thought, significantly increasing the rise of global sea levels in recent years, according to a new research by a group of United States and UK scientists.

"This has to be a cause for concern for the governments we trust to protect our coastal cities and communities", he said.

Such a rise alone sounds little but would make coastal floods during storms at high tides more damaging, he said.