As ice sheet melts, Antarctica’s bedrock rises
Part of western Antarctica’s bedrock is rising at one of the fastest rates ever recorded, potentially slowing the rise in sea levels.
Researchers, led by Ohio State University geology professor Terry Wilson, found that the bedrock underneath an ice sheet roughly the size of Texas, called the Amundsen Sea Embayment in western Antarctica, is rising 1.6 inches per year.
“This is extremely good news,” said Valentina Barletta, who started the research at Ohio State and is now a postdoctoral researcher at the National Space Institute at the Technical University of Denmark. “Something incredible is going on there.”
This happens all over the world as ice melts and weight is lifted off the bedrock, Barletta said. In fact, North America is still “bouncing back” from the last Ice Age.
The “uplift rate” is much slower in other parts of the world. Alaska, for instance, has a rate of less than an inch per year.
Researchers used several GPS stations to measure the rising bedrock beginning in 2008. They also measured the thickness of the ice during this period.
“There were never measurements of the inside Earth structure Ohio State researcher Terry Wilson, on Franklin Island in the Ross Sea, is leading a team of researchers in Antarctica. made like this before,” Wilson said. This study could help scientists predict future sea levels, she said.
Doug Wiens, an earth science professor from Washington University who also participated in the study, said that although Ohio has no coastlines, its residents still will be affected by rising sea levels.
“Ohio taxpayers had to support the costs of paying for Hurricane Sandy, which was made somewhat worse by sea level rise,” Wiens said.
This uplift could make a significant difference in the sea level.
Increasing temperatures have caused ice sheets to melt, putting more water into the world’s seas. But the uplift in west Antarctica is causing ice there to retreat more slowly, or to “stabilize,” Barletta said. This means that, in the right conditions, less of this ice could melt into the ocean.
“In 100 years, New York is going to be under a meter of water in some places,” Barletta said. “If we reduce (carbon) emissions, this could be the difference between a meter of water and a half-meter of water.”
The study will also be helpful for future research into the continent because it provides a more-accurate picture of what lies underneath the ice in western Antarctica, Wilson said.
“It’s not good news west Antarctica is losing enough ice that the earth (beneath it) is rising that fast,” Wilson said. “But this is important for predicting how change proceeds in the coming decades.”
Barletta echoed that sentiment, adding: “In an extreme climate situation, this uplift won’t help or change anything.”