Global ice loss has increased by 65 percent in two decades

Global ice loss has increased by 65 percent in two decades. Global ice loss has now reached a new record pace, according to a study from the University of Leeds. The researchers found that Earth lost 28 trillion tons of ice between 1994 and 2017. This amount is equivalent to a sheet of ice 100 meters thick covering the entire UK.

The experts used satellite data to investigate the evolution of ice on a global scale. They determined that the overall rate of ice loss has substantially increased within the past three decades, jumping from 0.8 trillion tons per year in the 1990s to 1.3 trillion tons per year in 2017.

Melting ice is a major concern due to its potential to raise sea levels, increase the risk of flooding to coastal communities, and destroy valuable ecosystems. 

The study revealed that in the last 23 years, there has been a 65 percent increase in the rate of ice loss. The primary cause of the spike is tied to major losses from the polar ice sheets in Antarctica and Greenland driven by global warming.

“Although every region we studied lost ice, losses from the Antarctic and Greenland ice sheets have accelerated the most,” said study lead author Dr Thomas Slater.

“The ice sheets are now following the worst-case climate warming scenarios set out by the Intergovernmental Panel on Climate Change. Sea-level rise on this scale will have very serious impacts on coastal communities this century.”

Dr Slater said the study is the first of its kind to examine all the ice that is disappearing on Earth using satellite observations.

“Over the past three decades there’s been a huge international effort to understand what’s happening to individual components in Earth’s ice system, revolutionised by satellites which allow us to routinely monitor the vast and inhospitable regions where ice can be found,” said Dr. Slater.

“Our study is the first to combine these efforts and look at all the ice that is being lost from the entire planet.”

Just over half of the ice loss was from the northern hemisphere, and the remainder was from the southern hemisphere. The biggest losses were from Arctic Sea ice and Antarctic ice shelves.

“Sea ice loss doesn’t contribute directly to sea level rise but it does have an indirect influence. One of the key roles of Arctic sea ice is to reflect solar radiation back into space which helps keep the Arctic cool,” explained study co-author Dr. Isobel Lawrence.

“As the sea ice shrinks, more solar energy is being absorbed by the oceans and atmosphere, causing the Arctic to warm faster than anywhere else on the planet.”

“Not only is this speeding up sea ice melt, it’s also exacerbating the melting of glaciers and ice sheets which causes sea levels to rise.”

Overall, the ice loss pinpointed in the study has raised global sea levels by 35 millimeters. It is estimated that for every centimeter of sea level rise, approximately one million people are in danger of being displaced from low-lying areas. 

Glaciers have contributed to almost a quarter of the global ice lost during the survey period, despite the fact that they store only one percent of the Earth’s total ice volume. 

“As well as contributing to global mean sea level rise, mountain glaciers are also critical as a freshwater resource for local communities,” said study co-author Inès Otosaka. “The retreat of glaciers around the world is therefore of crucial importance at both local and global scales.”

The study is published in the journal The Cryosphere.

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By Chrissy Sexton, Earth.com Staff Writer