The Earth has lost 28 trillion tonnes (approximately 31 trillion U.S. tons) of ice in just 23 years, and the climate crisis is largely to blame.
The finding comes in a review paper published in The Cryosphere this month that used satellite data and numerical modeling to calculate all the ice that melted worldwide between 1994 and 2017.
“In the past researchers have studied individual areas – such as the Antarctic or Greenland – where ice is melting. But this is the first time anyone has looked at all the ice that is disappearing from the entire planet,” study coauthor and director of Leeds University’s Centre for Polar Observation and Modelling Andy Shepherd told The Guardian. “What we have found has stunned us.”
Over 28,000,000,000,000 tonnes of ice has melted in last 30 years – enough to cover the entire surface of the UK in >100 metres thick ice – this is on trajectory for 1m of sea-level rise by 2100, the upper outcome range of @IPCC_CH – each 1cm rise will displace 1 million people. pic.twitter.com/Ltoqb7OFrt— Prof. Dan Parsons 🇪🇺 🌏💧🛰🌊⚽️🏏⛳🏈 (@bedform) August 23, 2020
Arctic sea ice, Antarctic ice shelves, mountain glaciers, the Greenland and Antarctic ice sheets, and Southern Ocean sea ice all lost mass during the study period, the researchers wrote. About 68 percent of those losses were caused by warmer air temperatures, while the remaining 32 percent were caused by warmer ocean water.
“There can be little doubt that the vast majority of Earth’s ice loss is a direct consequence of climate warming,” the researchers wrote, as The Guardian reported.
In fact, the total ice loss recorded matches the worst-case scenario predicted by the Intergovernmental Panel on Climate Change (IPCC). And it’s likely to get worse. The researchers prognosticate a meter (approximately three feet) of sea level rise by 2100.
“To put that in context, every centimeter of sea level rise means about a million people will be displaced from their low-lying homelands,” Shepherd told The Guardian.
But sea level rise isn’t the only consequence of ice melt. For one thing, the melting ice exposes darker ocean waters or soil, which absorb the sun’s heat rather than reflect it, increasing global heating. The freshwater melting from ice sheets also disrupts Arctic and Antarctic ocean ecosystems, while the loss of mountain glaciers threatens the drinking water of several communities.
“What more can be said? What further evidence are we waiting for?” UK Green Party co-leader Caroline Lucas tweeted in response to the news. “Feel so overwhelmingly sad – and so angry too. We can’t say we didn’t know. Are we really saying we just didn’t care?”
What more can be said? What further evidence are we waiting for?— Caroline Lucas (@CarolineLucas) August 23, 2020
Feel so overwhelmingly sad – and so angry too
We can’t say we didn’t know
Are we really saying we just didn’t care? #ClimateEmergency #CEEBill @CEEbill_NOW https://t.co/QUx0M0Pu6M
This has been a bad summer for ice news. Another study published this month found that Greenland’s ice sheet had reached the “point of no return” and would continue to melt even if the climate crisis were halted. A third study found that Greenland lost a record amount of ice in 2019.