This phenomenon is attributed to plate tectonics and the rock movement resulting from the melting of substantial ice sheets above, which alleviates the underground pressure. A new study published in Geophysical Research Journal: Solid Earth highlights that the pressure has been decreasing in recent years due to significant ice melt in Greenland, alongside the ongoing influence of colossal ice masses that have melted since the peak of the last ice age around 20,000 years ago. Consequently, the entire island has shifted northwest by approximately 2 centimeters annually over the past two decades.
Horizontal land movement observed by 58 GNET stations in Greenland. Image credit: Longfors Berg et al., doi: 10.1029/2024JB030847.
“Overall, this indicates that Greenland is gradually decreasing in size; however, with the accelerated melting currently observed, this could potentially change,” stated Dr. Danjal Longfors Berg, a postdoctoral researcher at the Technical University of Denmark and NASA’s Jet Propulsion Laboratory.
“The geophysical processes influencing Greenland’s structure are being exerted in various directions.”
“The region actually expanded during this timeframe, as the melting ice over the past few decades caused Greenland to extend outward and resulted in uplift.”
“Simultaneously, we are observing shifts in the opposite direction: Greenland is both rising and contracting due to alterations in the ancient ice mass associated with the last Ice Age and its conclusion.”
This marks the first detailed description of horizontal movement.
“We have constructed a model illustrating movement over an extensive timescale, from around 26,000 years ago to the present,” remarked Dr. Longfors-Berg.
“Additionally, we are utilizing highly precise measurements from the past 20 years to scrutinize current movements.”
“This allows us to measure movement with great accuracy.”
The new measurements rely on data gathered from 58 GNSS stations (GPS) distributed across Greenland.
These stations monitor Greenland’s overall position, changes in bedrock elevation, and the dynamics of the island’s contraction and expansion.
“For the first time, we have measured with such precision how Greenland is evolving,” commented Dr. Longfors-Berg.
“It was previously believed that Greenland was primarily being stretched by dynamics related to recent ice melt.”
“However, unexpectedly, we also discovered extensive areas where Greenland is converging or contracting as a consequence of this movement.”
This new research offers valuable insights into the potential impacts of accelerated climate change in the Arctic, as observed in recent years.
“Understanding the movements of land masses is crucial,” asserts Longfors-Berg.
“While they are certainly of interest to geosciences, they also hold significance for surveying and navigation, as even Greenland’s fixed reference points are shifting over time.”
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D. Longfors Berg et al. 2025. Estimation and attribution of horizontal land motion measured by the Greenland GNSS network. JGR: Solid Earth 130 (9): e2024JB030847; doi: 10.1029/2024JB030847
Source: www.sci.news
