Greenland, one of the primary sources of meltwater that inundates Earth’s shores, is actually rising faster than the rising oceans in a humorous quirk of physics.

Small islands and skerries like Uunartoq Qeqertaq are among the new land that is being progressively born in Greenland’s sea due to the raising bedrock. This new landmass off the east coast of Greenland, which translates to “warming island,” was formally recognised and added to the country’s maps in 2005. It is 13 kilometres (8 miles) long.

“The land uplift we observe in Greenland these years cannot be solely explained by the natural post-ice age development,” Technical University of Denmark (DTU) geodesist Shfaqat Abbas Khan. “Greenland is rising significantly more.”

Since the last ice age 12,000 years ago, Greenland has been progressively rising as its frozen layer of water has been steadily leaking into the sea. However, the melting process has been happening far more quickly, according to data from 58 GPS sites spread out across the nation (GNET).

Greenland’s bedrock has risen up to 20 centimetres (7.9 inches) in the last decade, at a rate of nearly 2 metres (6.6 feet) each century, according to DTU geodesist Danjal Longfors Berg and colleages.

“There are our data from GNET, we can precisely isolate the part of land uplift caused by the current global climate changes,” Khan states.

Even though the glaciers surrounding Greenland’s edge only account for 4% of the island’s total ice cover, they are nearly 15% of the cause of its ice loss. It turns out that the elevation of the land mass is also greatly aided by this disproportionate decrease.

Because of a phenomenon known as elastic rebound, the mass loss from these outer glaciers is contributing to an increase in certain places that is even higher than the loss of the main Greenland ice sheet.

Here, like a squished pillow released to take up greater volume, the formerly compacted earth relaxes into its more naturally expanded shape after being freed from the weight of the surroundings.

The highest uplift the scientists detected was caused by the retreated 10 kilometres Kangerlussuaq ice in south Greenland, that is equivalent to 8 millimetres each year.

The decline of the main ice sheet has been taken into account in previous studies, but the peripheral ice had not been properly taken into account until recently. Researchers will be able to estimate sea rise more accurately if they have a better grasp of the uplift.

“These are quite significant land uplifts that we can now demonstrate. They indicate that local changes in Greenland are happening very rapidly, impacting life in Greenland,” Berg says.

This strange occurrence is just one more example of how climate change is drastically altering the physical landscape of our planet. The Earth’s axis moving and the shrinkage of an entire layer of our atmosphere are past examples.

The Earth is truly being reshaped by us.


Topics #Earth's shores #Glacier Fringe #Greenland #Physics