The ice of Greenland is starting to melt faster than at any time in the last 12,000 years, according to research, which will raise sea levels and could have a significant effect on ocean currents.
New measurements show the melting rate matches anyone in the Holocaust geological record – defined as the period since the last ice age – and is likely to accelerate, according to published document in the Nature magazine.
Increased ice loss is likely to lead to sea level rise between 2cm and 10cm by the end of the century from Greenland only, according to the study.
Jason Briner, professor of geology at the University of Buffalo and lead author of the paper, said: the last 12,000 years. “
These changes, in a relatively short period of less than a century, seem to be unprecedented. Greenland ice sheet shrank 10,000 to 7,000 years ago and has accumulated slowly over the last 4,000 years. Current melting will reverse this pattern, and within the next 1,000 years, if global warming continues, the huge ice sheet is likely to disappear completely.
If greenhouse gas emissions continue to rise sharply, the rate of melting could accelerate further to four times that of the last 12,000 years.
“We are increasingly confident that we will experience unprecedented rates of ice loss from Greenland unless greenhouse gas emissions are significantly reduced,” wrote Andy Aschwanden, of the Geophysical Institute at the University of Alaska at Fairbanks. .
The findings underscore the extent of the changes that human energies are destroying the planet. Last week, a special team of scientists found it melting of Antarctic ice will continue even if the people fulfill the Paris agreement, the goal of maintaining the temperature to rise to 2C and eventually raise the sea level by 2.5 meters to this level of heating.
Although the Antarctic ice sheet, like the Greenland ice sheet, will take centuries to melt, the study found that the melting motion driven by human climate change was likely to be extremely difficult, if not impossible. , to be reversed.
Arctic ice is also melting rapidly. This year’s minimal ice in the sea was the second lower the last 40 years of continuous measurements. Unlike the Greenland ice, which is on land, the Arctic’s cap floats and so its melting will not have much impact on sea level.
However, it is melting further accelerates the rise in temperature reducing the earth’s albedo – the reflection of light back into space from ice – and exposing the darker water below, which absorbs more heat.
The findings as well follow a study last month found that last year’s meltdown in Greenland was probably the worst in centuries.
The team behind the latest Greenland study made its estimates, producing a computer model of a section of the southwestern ice region for the past 12,000 years and then projecting it forward by the end of this century.
They checked their findings in relation to what can be said to have actually happened to the ice, through satellite measurements and other instruments, as well as by mapping the location of beryllium-10-containing boulders.
These are deposited by glaciers as they move, and beryllium-10 measurements can reveal how long the boulders were in place, and therefore where the edge of the ice sheet was when the stone was deposited.
“Before our study, science did not matter much about the long-term trends in Greenland’s ice loss rate,” Briner said.
“A lot of meticulous work has been done to quantify the current rates of ice loss in Greenland, but we did not have a long-term view to put the current rates in perspective. Our study provides this perspective. “