ANCHORAGE, Alaska (Reuters) – Earth’s ice is melting faster today than in the mid-1990s, according to new research, as climate change pushes global temperatures higher and higher.
In all, an estimated 28 trillion metric tons of ice has been dumped from the world’s sea ice, ice sheets and glaciers since the mid-1990s. Annually, the melting rate is now 57 percent faster than three decades ago, scientists report in a study published Monday in The Cryosphere.
“It was a surprise to see such a big increase in just 30 years,” said co-author Thomas Slater, a glaciologist at the University of Leeds in Britain.
While the situation is clear to those who depend on mountain glaciers to drink water or who depend on winter sea ice to protect homes on the coast from storms, the world’s ice thaw has begun to draw attention away from the icy regions, Slater noted.
Aside from being captivated by the beauty of the polar regions, “people recognize that while the ice is far away, the effects of the fusion will be felt,” he said.
The melting of land ice – in Antarctica, Greenland and mountain glaciers – added enough water to the ocean over the three-decade period to raise the average global sea level by 3.5 centimeters. Ice loss from mountain glaciers accounted for 22 percent of total annual ice losses, which is noteworthy considering that it only accounts for about 1 percent of all land ice on earth, dir Slater.
Across the Arctic, sea ice is also falling to new summer lows. Last year saw the second lowest stretch of sea ice in more than 40 years of satellite surveillance. As sea ice fades, it exposes dark water that absorbs solar radiation instead of reflecting it out of the atmosphere. This phenomenon, known as Arctic amplification, further increases regional temperatures.
Global atmospheric temperature has risen about 1.1 degrees Celsius since pre-industrial times. But in the Arctic, the warming rate has more than doubled the world average over the past 30 years.
Using satellite data from 1994-2017, site measurements and some computer simulations, the team of British scientists estimated that the world lost an average of 0.8 trillion metric tons of ice a year in the 1990s. , but about 1.2 trillion metric tons annually in recent years. .
Calculating even an estimated total of ice losses from the world’s glaciers, ice sheets and polar seas is “a really interesting approach and one that is actually quite necessary,” said Division geologist Gabriel Wolken. of Alaska Geology and Geophysics. Wolken was co-author of the Arctic Report Card 2020 released in December, but did not participate in the new study.
In Alaska, people are “very aware” of glacial ice loss, Wolken said. “You can see the changes with the human eye.”
Researcher Julienne Stroeve, of the National Snow and Ice Data Center in Boulder, Colorado, noted that the study had not included snow cover on the ground, “which also has strong albedo feedback,” referring to -se to a measure of the reflecting surface.
The research also did not take into account the ice or permafrost of the river or lake, except to say that “these elements of the cryosphere have also undergone considerable changes in recent decades.”
Report by Yereth Rosen; Edited by Katy Daigle and Philippa Fletcher