Thanks in part to support from NASA and the National Science Foundation, scientists have produced the first-ever detailed maps of bedrock beneath glaciers in Greenland and Antarctica. This new data will help researchers better project future changes to glaciers and ice sheets, and ultimately, sea level.
Researchers at the Center for Remote Sensing of Ice Sheets, or CReSIS, at the University of Kansas in Lawrence, Kansas, recently built detailed maps of the terrain beneath Greenland’s Jakobshavn Glacier and Byrd Glacier in Antarctica.
The results of this study were published in the September issue of the Journal of Glaciology. CReSIS is a major participant in NASA’s Operation IceBridge, a NASA airborne science mission aimed at studying Arctic and Antarctica land and sea ice.
CReSIS researchers used computer software to process and analyze data collected during field campaigns unrelated to IceBridge that were conducted in cooperation with NASA and NSF in 2008 and 2011 to build maps of the two glaciers.
These data were from an ice-penetrating radar instrument known as the Multichannel Coherent Depth Sounder / Imager, or MCoRDS / I, which is similar to the instrument IceBridge has used since 2009. Bed topography data are vital for computer models used to project future changes to ice sheets and their contribution to sea level rise. “Without bed topography you cannot build a decent ice sheet model,” said CReSIS director Prasad Gogineni.
Jakobshavn Glacier is of interest because it is the fastest-moving glacier in the world and drains about 7.5 percent of the Greenland Ice Sheet. Having a map of Jakobshavn’s bed has been a long-time goal of glaciologists. Byrd Glacier is also moving faster than average, but unlike many other glaciers, has been sounded in the past. Researchers mapped a previously unknown trench beneath Byrd Glacier and found that depth measurements from the 1970s were off by as much as a half mile in some places.
Ice-penetrating radar is one method for mapping bedrock topography. The instrument sends down radar waves, which reflect off of the ice surface, layers inside the ice sheet and bedrock back to the instrument, giving researchers a three-dimensional view. Ice-penetrating radar data from IceBridge flights helped build maps of Greenland and Antarctica’s bedrock and were even used to discover a large canyon beneath the ice in northern Greenland.
Imaging rock beneath glaciers like Jakobshavn is important, but more difficult than mapping the ice sheet interior. The relatively warm ice and rough surfaces of outlet glaciers weaken and scatter radar signals, making the bed difficult to detect. To overcome these challenges, CReSIS used a sensitive radar instrument with a large antenna array and used several processing techniques to remove interference and build a view of sub-ice bedrock. “We showed that we have the technology to map beds,” said Gogineni.
The MCoRDS / I instrument can be traced back to an early ice-penetrating radar CReSIS designed and built in the mid-90s in cooperation with NASA and NSF. In the two decades since then CReSIS has refined this instrument and has flown on NASA aircraft and alongside NASA instruments.
Researchers continue to improve instrument hardware and data processing and are looking ahead to mapping more glaciers in the future, which will likely involve small, unmanned aerial vehicles. “Improving ice sheet models means we need even finer resolution,” Gogineni said. “To do this we need lines flown much closer together, which small UAVs would be well suited for.”
For more information on NASA's Operation Ice Bridge, visit:
For more information about the Center for Remote Sensing of Ice Sheets, visit:
George Hale | Eurek Alert!
Greenland ice flow likely to speed up: New data assert glaciers move over sediment, which gets more slippery as it gets wetter
17.08.2017 | Swansea University
Climate change: In their old age, trees still accumulate large quantities of carbon
17.08.2017 | Universität Hamburg
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences