We can still prevent a climate disaster, but time is running out. How much time do we have before ‘no need to return’?
Research now published indicates that an important tipping point has already been passed.
Between 1900 and 2016, global warming caused sea levels to rise between 16cm and 21cm.
Some studies suggest that by the end of this century they may have been as high as 2.7 meters.
The second largest contributor to that rise would be the Greenland Ice Sheet; It is melting in the sea.
The run-off from the Antarctic Peninsula is just over.
At 3,000 km long and up to 1,100 km wide, the ice block covers 80% of Greenland, the second largest island in the world. It is the largest mass in the Northern Hemisphere, with a thickness of more than 2 km in places.
In addition to the large central block, there are isolated glaciers within the country.
Snow falls on the surface of the ice sheet. Some of them melt and flow into streams, but most freeze and turn into ice sheets. Glaciers are not static; They gradually move into the sea. The ice melts more rapidly under water and the process accelerates as the ocean temperature rises. The best blocks turn into ‘calf’, snowy mountains.
Ice cubes are similar to bank accounts: when income does not include expenses, bankruptcy increases.
If enough ice builds up to replace the melting water, the number of ice sheets will remain black. If not, it will go red and the block will be destroyed. The snow-covered white landscape reflects light from the sun into space, known as the ‘albedo effect’.
As the ice disappears and the glacier fronts recede, the groundwater is exposed, resulting in more radiation from the sun being absorbed by the earth as heat. Like avalanche, it accelerates the melting process.
Michaelia King of Ohio State University examined data collected by remote sensors from the Greenland glaciers over the past three decades.
There are continuous records for 128 glaciers from 1985 to 2018. Miss King estimates the speed, elevation, and anterior changes of the outlet glacier rather than the full ice sheet.
The sheet “loses mass for several decades,” her research reveals.
Between 1992 and 2018, the loss was mainly in water flowing from the block surface rather than melting glaciers. Recently, however, she and her co-authors say, “Increased glacial discharge is more likely to be a retreat of glacier fronts than inland ice-sheet processes.”
There is no hope that the decline will stop: “the possibility of change in the future”, says Miss King, “uncertainty”.
Between 2000 and 2005, there was a “step-up increase in discharge and a transition to a new, dynamic state of stable mass that persists even as the surface melting decreases.” Despite global warming, the Greenland ice sheet will shrink and deposit its molten water in the ocean.
Compassion with poor polar bears, walruses and seals.