Page 2/2 - Posted October 14, 2011
Scientists take to the field, skies to learn more about West Antarctica
Another major NSF-funded project tackling ice sheet dynamics is WISSARD , for Whillans Ice Stream Subglacial Access Research Drilling. A multiyear, multidisciplinary program, WISSARD will explore the subglacial lake system that exists at the boundary between West Antarctica and the Ross Ice Shelf .
Members of the WISSARD team presented some of the findings from recent fieldwork to map one of the key sites in their investigation, subglacial Lake Whillans, with radars and seismic imaging. In coming years, researchers will use a hotwater drill to access the lake and other parts of the subglacial waterworks, sending robots and instruments into the ice-covered environment to learn more about its mysteries and the role it plays in ice sheet dynamics.
Few among the group would dispute that future research in West Antarctica and elsewhere will increasingly rely on remote sensing — instruments aboard satellites or aircraft that can provide various details about the ice regarding its thickness, layers and even motion.
Bernd Scheuchl , an associate project scientist at the University of California-Irvine’s Department of Earth System Science , presented work done by Eric Rignot’s research group that created a digital mosaic of ice motion covering all of Antarctica.
Using satellite data from the Japanese, Canadian and Europeans, the NASA-funded, color-coded map shows where ice drains from the interior to the exterior of the continent. The colors represent the speed of the ice, making the animated map that Scheuchl presented look like thick-trunked trees (where the glaciers flow to the sea or terminate at ice shelves), with bristling branches (where small rivers of ice begin to stream from the interior).
Graphic Credit: NASA/JPL-Caltech/UCI
First complete map of the speed and direction of ice flow in Antarctica, derived from radar interferometric data.
Recent air campaigns above Antarctica are also changing the way scientists see the continent.
A project called ICECAP , for Investigating the Cryospheric Evolution of the Central Antarctic Plate, created a new topographical map of the bedrock below the East Antarctic Ice Sheet that revealed some of the largest fjords, or ice-cut channels, on Earth.
For three field seasons, the research team flew an upgraded World War II-era DC-3 aircraft with a suite of geophysical instruments to study the ice and underlying rock below Antarctica’s larger ice sheet. The findings from the project, partly funded by NSF, should provide important insight into the history of ice in Antarctica, as well as improve computer models of how the ice sheet might behave in the future as the climate changes. [See previous article: Capped off.]
“We are moving into a different world,” noted Duncan Young , a research scientist at The University of Texas at Austin’s Institute for Geophysics who presented the ICECAP data at the workshop, referring to the recent discoveries about Antarctica that are changing how scientists understand its ice dynamics.
ICECAP will continue mapping East Antarctica’s ice for another two field seasons, as part of the NASA initiative called Operation IceBridge . The six-year program, spanning both Antarctica and Greenland, began its third campaign in the Antarctic this month. The goal of IceBridge is to bridge the gap between the data provided by a satellite called ICESat-1 , which stopped operating in 2009, and the launch of its successor, ICESat-2, in 2016. [See previous article: NASA IceBridge.]
The 2011 Antarctic IceBridge campaign will feature the return of NASA’s DC-8 , the agency’s largest plane in its airborne research fleet. This year’s program will also include for the first time the Gulfstream V , which is operated by the NSF and National Center for Atmospheric Research (NCAR) . ICECAP’s modified DC-3 will fly across parts of East Antarctica where the other two planes can’t reach from their base of operations in Punta Arenas, Chile.
“The areas where we go and collect data are pretty much defined by where changes are happening, where we see changes happening in satellite missions,” said Michael Studinger , project scientist at NASA Goddard Space Flight Center .
That seems to be the mantra the workshop scientists have adopted — go where the changes are happening. The question of how Antarctica will respond in a changing world will take them to crevassed ice shelves and ice-choked seas. It will require innovative technologies aboard aircraft or robots sent to explore subglacial seas.