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Greenland’s ice sheet is the hottest it has ever been and will cause global sea levels to rise 20 inches by 2100 if it continues to warm at the same rate, scientists have warned.
From 2001 to 2011, temperatures at high elevations were 2.7°F (1.5°C) warmer than in the 20th century, representing the warmest decade in the last thousand years.
That’s based on a reconstruction of north-central Greenland temperatures from 1100 to 2011 by experts at the Alfred Wegener Institute.
Over the past 30 years, Greenland’s contribution to global sea level has grown significantly as ice melt increases, with a major recent report finding that it is losing ice seven times faster than during the 1990s.
Concern: Greenland’s ice sheet is hotter than ever and will cause global sea level to rise 20 inches by 2100 if it continues to warm at the same rate, scientists warn
From 2001 to 2011, temperatures at high elevations were 2.7°F (1.5°C) warmer than in the 20th century, representing the warmest decade in the past 1,000 years.
It is even feared that the ice cap has passed a point of no return.
It has been suggested that all of Greenland will melt as a result of the level of global warming that the world is already committed to due to carbon emissions.
The Greenland ice sheet plays an important role in global climate due to its size, radiative effects, and storage of around three million cubic kilometers of fresh water.
Weather stations along the coast of the ice sheet have been recording rising temperatures for many years, but scientists have been largely in the dark about how global warming is influencing areas elevated up to 9,800 m. feet (3,000 meters).
This is due to a lack of long-term observations, which is what led the researchers involved in the new study to reconstruct past temperatures.
The result shows clear evidence that climate change has reached the remote parts of north-central Greenland.
“The time series we recovered from the ice cores now continuously covers more than 1,000 years, from the year 1000 to 2011,” said glaciologist Dr. Maria Hörhold, lead author of the research.
‘These data show that the warming from 2001 to 2011 clearly differs from natural variations over the past 1,000 years.
“Although we were grimly expecting in light of global warming, we were surprised by how apparent this difference really was.”
Dr. Hörhold and her colleagues came to this conclusion by analyzing the isotope composition in shallow ice cores.
Earlier samples from the 1990s did not indicate clear warming in north-central Greenland, despite rising global mean temperatures, which experts say is partly due to the region’s natural climate variability.
But the researchers have now expanded on these earlier data sets by re-drilling the ice sheet during a series of expeditions back to 2012.
The temperatures were then reconstructed by measuring the concentrations of stable oxygen isotopes within the ice, which vary with temperatures at the time of ice formation.
The calculations are based on a reconstruction of north-central Greenland temperatures from 1100 to 2011 by experts at the Alfred Wegener Institute.
The researchers expanded previous data sets on ice melt and high-altitude temperatures by re-drilling the ice sheet during a series of expeditions through 2012 (pictured)
Estimates: The temperatures were then reconstructed by measuring the concentrations of stable oxygen isotopes within the ice, which vary with temperatures at the time of ice formation.
In addition to estimating temperature changes, the team reconstructed how much the layer has melted and found that it has increased substantially since the 2000s, contributing to a rise in global sea levels.
If it continues as is, without action to curb global warming, sea levels will rise 20 inches (50 cm) by 2100, the researchers said.
They found that, on average, the reconstructed temperature for 2001-2011 was 3°F (1.7°C) warmer than that for the period 1961-1990 and 2.7°F (1.5°C) warmer. than that of the 20th century as a whole.
“We were surprised to see how closely connected inland temperatures are with meltwater drainage across Greenland, which, after all, occurs in low-elevation areas along the edge of the ice sheet near the coast.” , added Dr. Hörhold.
To delve deeper into the connection between ice melt at the edges of the ice sheet and high-altitude temperatures, the scientists used data from a regional climate model from 1871 to 2011 and combined it with satellite observations from 2002 to 2021.
This allowed them to convert the temperature variations identified in the ice cores into melt rates and provide estimates for the past 1,000 years.
They hope their research will provide a greater understanding of how the ice sheet melted in the past, as well as improve projections of future sea level rise.
The study has been published in the journal Nature.