Frozen Flows
UCI research shows glaciers are moving faster than once thought.
Brittany Hanson, Orange County Register
Glaciers are fast – much faster than scientists previously thought – and their speeds are increasing, according to a UC Irvine research team mapping ice movement in Antarctica for NASA.
“When they (speed up), it’s not a trickle,” said Eric Rignot, a UC Irvine professor of Earth System Science and lead project researcher. They increase in speed by three, or eight – sometimes even 10 times their initial rate of movement, he said.
Rignot and his team just secured a $2.6 million grant from NASA to continue mapping ice, including the massive glaciers, in Antarctica – from the inner continent to the coast.
It’s the first such detailed map to cover the entire continent, said Bernd Scheuchl, associate project scientist. The team uses information feeds from American, European and Japanese space satellites – none of which is designated for the project or have a specific mission to complete the mapping, Scheuchl said.
This is the second grant from NASA for the project, which began in 2007. The study has indicated that ice is moving and melting much faster than previously thought, something the team says is causing sea levels to rise.
The information comes to the team in data strips, one after another. “Think of it, the strips, as lines that wrap over and around. Like a spool of wool, in a full line around the planet and we just use this area,” Rignot said.
It took 1,300 “strips” of information, 40 terabytes of data, to map the continent.
The earliest data used was from 1996 and the imagery it provided is comparable to pictures taken with the first camera phones, said Rignot.
“Now, imagine a much clearer image, such as we would have now with a smartphone camera,” he
said. “It is the satellite version of retina display.”
Now they must create another map over the course of four to five years to have a complete comparative image.
The high speed of ice movement, though fluctuating, is likely to last at least until the year 2100, and
there’s probably nothing humans can do about it, Rignot said.
“Of course, (glaciers melt),” Rignot said. “But what we need to find out is how fast they will melt now
and how fast in the future.”
“We would like to be able to quantify what they (glaciers) are doing. We know hey are rising the sea level, we have known for a long time. We just didn’t know how fast it is going to happen and a lot of the models we have been relying on to do these projections don’t work,” Rignot said.
What has been found in this study is that the speed of Antarctic ice movement has increased dramatically, raising sea levels worldwide, Rignot said. Sea level rise could be as small as a few centimeters or as much as two meters, depending on the amount of ice and number of years, he said.
For Californians near the coast, it will mean less beach space and a higher potential for flooding, Rignot said. He predicts that if the current speeds keep up, there could be two meters less of beaches in some parts of the world by the year 2100.
This flow from the inner continent to the Antarctic coast also poses potential changes to how ocean circulation moves.
All of this was garnered from five years of snapshots from space.
Rignot wants the information to be provided not just to the scientific community at large, but to politicians and governments who can have an impact on environmental policy.
The goal is to be able to illustrate the differences in the ice sheets and provide the information needed for those policy makers to impact environmental changes, Rignot said.
“Smart people all over the world could be looking at these difficult problems and provide more tools to see what can be done. People who make decisions can use or not use it … and take that knowledge and make their own decisions.”
