New research suggests that the bedrock below the West Antarctic Ice Sheet (WAIS) is advancing at what appears to be close to record speeds, and possibly “putting the brakes” on the continent’s ice melt.
In a study published this week in the journal Science, a team of researchers confirmed what could be a rare example of good news for Antarctica’s ice sheets, particularly the WAIS, which has often been thought as being “doomed” due to the effects of man-made climate change, according to Phys.org. With the ground beneath the sheet rising at a surprisingly fast rate, that makes the ice sheet substantially more stable, as the added support could stave off a possible collapse due to ice loss in the area.
As further explained by Axios, ice melt has resulted in a lower amount of weight being placed on the supporting bedrock. This, in turn, leads to glacial isostatic adjustment, a phenomenon also known as rebound, as the ground continues to rise. According to the researchers, a quick rate of rebound could curb ice loss in the West Antarctic Ice Sheet, contrary to previous studies that had warned of its imminent collapse.
Although the numbers might not seem too significant at first glance, the study nonetheless described the rate of rebound underneath West Antarctica’s Amundsen Sea Embayment as being unusually quick at approximately 41 millimeters a year. Assuming this trend continues as expected, with rebound below the WAIS moving up to 3.5 times faster in the next 100 years as compared to the present, this could mean that the grounding line, or the point where the Pine Island Glacier’s ice shelf meets bedrock, will rise by over 26 feet (eight meters) in a century’s time.
According to Ohio State University professor emeritus of earth science Terry Wilson, who co-authored the study, the rebound, or “uplift rate” recorded below the WAIS was a “game changer,” as uplift rates in areas such as Iceland and Alaska are already considered rapid at about 20 to 30 millimeters annually.
“These results provide an important contribution to our understanding of the dynamics of the Earth’s bedrock, along with the thinning of ice in Antarctica. The large amount of water stored in Antarctica has implications for the whole planet,” commented study lead author Valentina R. Barletta, a postdoctoral researcher at the Technical University of Denmark’s National Space Institute.
“The new findings raise the need to improve ice models to get a more precise picture of what will happen in the future.”
Talking about existing models, Wilson said that she once believed the uplift process would take several thousands of years to play out in full, or way too slow to stabilize the West Antarctic Ice Sheet and protect it from the threat of ice melt. However, the new findings, which were based on a combination of GPS sensor and satellite readings, suggest that the process might take only a few decades. Furthermore, she added, the phenomenon could be a sign that Antarctica’s bedrock has different geological features than once thought, with its rebound being driven by a hotter and more viscous mantle than expected.
Despite the optimism indicated by the researchers in the new paper, Axios noted that multiple scientists who did not take part in the study have expressed “cautious optimism,” and stressed that more research might be necessary before concluding that the super-fast rebound rate can indeed slow down ice melt and prevent the WAIS from collapsing.