A total of 28 trillion tonnes of ice has disappeared from the earth’s surface since 1994. That is the stunning conclusion of UK scientists who have analyzed satellite studies of the planet’s poles, mountains and glaciers to measure how much ice cover has been lost. due to global warming triggered by increasing greenhouse gas emissions.
The scientists – based at the University of Leeds and Edinburgh and University College London – describe the level of ice loss as “staggering” and warn that their analysis indicates that sea level rise, triggered by melting glaciers and ice sheets, could eventually reach one meter. of the century.
“To put that in context, every inch of sea level rise means that about a million people will be displaced from their low-lying homelands,” said Professor Andy Shepherd, director of Leeds University’s Center for Polar Observation and Modeling.
Scientists also warn that melting ice in these hues is now seriously reducing the planet’s ability to reflect solar radiation back into space. White ice disappears and the dark sea as soil exposed beneath it absorbs more and more heat, further increasing the planet’s warming.
In addition, cold fresh water from melting glaciers and ice sheets causes major violations to the biological health of Arctic and Antarctic waters, while loss of glaciers in mountain ranges threatens to remove sources of fresh water on which local communities depend.
“In the past, researchers have studied individual areas – such as the Antarctic or Greenland – where ice melts. “But this is the first time anyone has looked at all the ice that is disappearing from the entire planet,” Shepherd said. “What we found surprised us.”
The level of ice loss revealed by the group is in line with the worst-case scenario predicted by the Intergovernmental Panel on Climate Change (IPCC), he added.
The group studied satellite studies of glaciers in South America, Asia, Canada and other regions; sea ice in the Arctic and Antarctic; ice sheets covering the ground in Antarctica and Greenland; and ice planes erupting from the Antarctic mainland into the sea. The study covered the years 1994 to 2017.
The researchers’ conclusion is that all regions have suffered devastating reductions in ice cover over the past three decades and that these losses continue.
“To put the losses we’ve already experienced into context, 28 trillion tonnes of ice would cover the entire surface of the UK with a plate of frozen water that is 100 meters thick,” added Leeds University team member Tom Slater. “It’s just mind-blowing.”
As for the cause of these huge losses, the group is adamant: “There can be little doubt that the vast majority of Earth’s ice loss is a direct result of global warming,” she said in her review paper, which is published in ‘ e online journal Cryosphere Discussions.
“On average, the planetary surface temperature has risen by 0.85C since 1880, and this signal has been amplified in the polar regions,” they state. Both the sea and atmospheric temperatures have risen as a result and the resulting double whammy has resulted in the catastrophic ice loss that the group discovers.
In the case of the melting ice sheet in Antarctica, rising sea temperatures have been the main driver, while rising atmospheric temperatures have been the cause of ice loss from inland glaciers such as those in the Himalayas. In Greenland, ice loss is triggered by a combination of both sea and atmospheric temperatures increasing.
The team claimed that not all the ice that was lost over that period would have contributed to sea level rise. “A total of 54% of the lost ice was from sea ice and from ice shelves,” said Leeds University researcher Isobel Lawrence. “These drifts on water and their melts would not have contributed to the rising sea level. The other 46% of meltwater came from glaciers and ice sheets on the ground, and they would have added to rising sea levels. ”
The group’s results were published 30 years after the publication of the IPCC’s first assessment report, at the end of August 1990. This wrote, in solid terms, that global warming was true and was triggered by increasing greenhouse gas emissions. from burning fossil fuels.
Despite warnings from scientists, these emissions continued to increase as global temperatures continued to stagnate. According to figures released by the Met Office last week, there was a 0.14C increase in global temperatures between the 1980-89 decade and the 1990-1999 decade, then a 0.2C increase between each of the following decades. This rate of increase is expected to increase, possibly to about 0.3C over the decade, as carbon emissions continue on their rise.
