- News Home
17 April 2014 12:48 pm ,
Vol. 344 ,
Officials last week revealed that the U.S. contribution to ITER could cost $3.9 billion by 2034—roughly four times the...
An experimental hepatitis B drug that looked safe in animal trials tragically killed five of 15 patients in 1993. Now,...
Using the two high-quality genomes that exist for Neandertals and Denisovans, researchers find clues to gene activity...
A new report from the Intergovernmental Panel on Climate Change (IPCC) concludes that humanity has done little to slow...
Astronomers have discovered an Earth-sized planet in the habitable zone of a red dwarf—a star cooler than the sun—500...
Three years ago, Jennifer Francis of Rutgers University proposed that a warming Arctic was altering the behavior of the...
- 17 April 2014 12:48 pm , Vol. 344 , #6181
- About Us
ScienceShot: What Killed Larsen B?
9 January 2014 11:15 am
In early 2002, a 200-meter-thick, Rhode Island–sized floating mass of ice attached to the Antarctic Peninsula unexpectedly shattered and floated away in a matter of weeks. While researchers quickly linked the breakup to lakes of meltwater that had accumulated on the so-called Larsen B ice shelf’s upper surface and then wedged apart deep crevasses, they hadn’t come up with a convincing explanation for what triggered the collapse. Now, a new analysis in Geophysical Research Letters suggests that the sudden drainage of one or more of those lakes, and not merely their presence, set off the disintegration. The team’s analyses show that when a meltwater lake drains through the ice sheet into the underlying sea, the ice nearby, suddenly relieved of the water’s weight, springs upward. That changes the patterns of stress in the ice, which ripple across the ice shelf and can cause nearby lakes to drain, setting up a chain reaction by which the entire lake-ridden portion of the ice shelf can splinter. Just before the collapse and its aftermath (shown as icebergs were dispersing on 7 March 2002), satellite images showed more than 2700 meltwater lakes on Larsen B’s surface. All of those lakes mysteriously and simultaneously drained just before the breakup commenced—a possible warning sign for future ice shelf collapses, the team contends.