New Study Shows Northern Greenland’s Glaciers are Rapidly Weakening
A new study published in Nature Communications has revealed that the once-stable glaciers in northern Greenland are now in trouble, as the region’s ice shelves are rapidly weakening. This could have potentially “dramatic” consequences for sea level rise, the study found.
Researchers analyzed eight ice shelves buttressing glaciers in northern Greenland, which collectively hold enough ice to raise sea levels by nearly 7 feet if they were to break down and melt completely. Since 1978, the ice shelves have lost more than 35% of their total volume, with three of them collapsing completely since the early 2000s.
The primary drivers of this ice loss were increased calving, where chunks of ice break off to form icebergs, surface melting, and basal melting, which occurs when warm ocean currents melt the ice from beneath. Since the early 2000s, there has been a widespread increase in the rate of basal melting closely following a rise in ocean temperature.
As the ice shelves melt, the grounding lines of glaciers – the point at which the glacier stops touching the ground and starts to float – are retreating, causing an increase in the ice discharge into the ocean. This contributes significantly to observed sea level rise, with the melting of Greenland’s ice sheet accounting for more than 17% of observed sea level rise between 2006 and 2018.
The future of the glaciers will depend heavily on what the world does to reduce planet-heating pollution. Continued monitoring is needed to assess how the ice shelves will respond to climate change and to build on the study’s findings about the complex process of basal melting and the potential impacts on sea level rise.
The study’s findings are significant in providing insight into sources and triggers of changes to Greenland’s ice sheet, according to Sophie Nowicki, an ice sheet expert at the University at Buffalo. It also adds to an overall understanding of how polar regions are responding to the human-induced climate crisis.
As the planet continues to heat up, the rapid changes in these dynamic and fragile regions should be of concern, Nowicki added. While the timing and magnitude of the changes are alarming, they should not come as a surprise in the face of the ongoing climate crisis.