While a global surge in ocean elevations is a documented phenomenon, Greenland is an anomaly, with projections indicating a notable decline in its coastal waters over the forthcoming decades.
A recent investigation, spearheaded by Lauren Lewright, a geophysicist affiliated with Columbia University, integrated empirical data with sophisticated computational simulations to forecast the shifts in relative sea level anticipated around Greenland throughout the current century.
“The environmental conditions along Greenland’s shores are poised for a significantly divergent trajectory,” stated Lewright.
The escalating increase in atmospheric greenhouse gases, which ensnare thermal energy that would otherwise be disseminated into the cosmos, is the primary driver of sea-level inflation.
A substantial portion of this captured heat is absorbed by the oceans, leading to the volumetric expansion of seawater. This process, known as thermal expansion, is projected to be the principal contributor to the overall augmentation of global sea levels in the future.
However, authoritative sources suggest that the diminishing of ice sheets will exert a considerable influence on Greenland’s future oceanic altitudes, which are predicted to recede rather than advance.
Greenland represents a unique situation due to the immense weight of a kilometer-thick ice sheet pressing down on its landmass, which blankets approximately 80 percent of the island’s territory.
Currently, this ice cover is diminishing at an annual rate of roughly 200 billion tons. As this immense pressure is alleviated, the underlying bedrock undergoes a process of uplift.
Under the most optimistic scenario, characterized by mitigated greenhouse gas emissions, the self-governing territory is calculated to experience an emergence of approximately 0.9 meters (roughly 3 feet) of new land as a consequence of subsiding sea levels by the close of the 21st century.
In the event that no measures are taken to curtail our greenhouse gas emissions, Greenland’s landmass is projected to elevate by a significant 2.5 meters (8.2 feet) from its current oceanic position.
Lewright and a collaborative team of researchers from the United States, the United Kingdom, and Canada formulated these projections by harmonizing empirical records of historical sea-level and land-elevation fluctuations with a computational model designed to forecast terrestrial displacement following the ablation of glacial ice.
Gravitational forces also play a consequential role in the observed elevational increases in Greenland.
“When the ice sheet is of considerable magnitude, it possesses substantial mass. The gravitational attraction exerted by this mass draws the adjacent sea surface towards the ice sheet,” explained Lewright.
“As the ice sheet diminishes in mass, its gravitational influence on the sea surface wanes. This gravitational reduction directly results in a recession of sea level.”
A resultant decrease in sea levels is expected to have ramifications for Greenland’s economy, its coastal infrastructural integrity, and the food security of its populace, which is predominantly concentrated in coastal communities.
The findings of this scientific endeavor have been disseminated in the journal Nature Communications.
