NASA’s Operation IceBridge captures images of Earth’s polar ice so we can better understand processes that connect polar regions with the global climate system.
Operation IceBridge is about to close in on the end of its eighth consecutive Antarctic deployment, and will likely tie with its 2012 campaign record for the most research flights carried out during a single season.
“We are probing the most remote corners of Spaceship Earth to learn more about changes that affect all of us locally, such as how ice sheets are contributing to sea level rise,” said NASA Deputy Administrator Dava Newman on her very first flight over Antarctica with the Operation IceBridge team on Nov. 17. “At NASA we explore not only space but also our home planet.”
“Operation IceBridge is particularly well suited to measure changes in polar ice: it carries probably the most innovative and precise package of instruments ever flown over Antarctica,” Newman said.
“This campaign was possibly the best Antarctic campaign Operation IceBridge has ever had,” said John Sonntag, IceBridge mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We flew as many flights as we did in our best prior campaigns down here, and we certainly got more science return out of each flight than we have before, due to steadily improving instrumentation and also to some excellent weather in the Weddell Sea that favored our sea ice flights.”
Antarctica is heading into austral summer, a period of rapid sea ice melt in the Southern Ocean. But this year the sea ice loss has been particularly swift, and the Antarctic sea ice extent is currently at the lowest level for this time of year ever recorded in the satellite record, which began in 1979.
IceBridge expanded its reach this year, covering a vast swath of Antarctica. During its six weeks of operations from its base in Punta Arenas, in the southernmost tip of Chile, Operation IceBridge carried out 24 flights over Antarctica. In total flying 308 hours.
One of this year’s missions flew over a massive rift in the Antarctic Peninsula’s Larsen C Ice Shelf. Ice shelves are the free parts of ice streams and glaciers, and they buttress the grounded ice behind them; when ice shelves collapse, the ice behind accelerates toward the ocean, where it then adds to sea level rise. Larsen C neighbors a smaller ice shelf that disintegrated in 2002 after developing a rift similar to the one now growing in Larsen C.
The IceBridge scientists measured the Larsen C fracture to be about 70 miles long, more than 300 feet wide and about a third of a mile thick. The crack completely cuts through the ice shelf, but it does not go all the way across it – once it does, it will produce an iceberg roughly the size of the state of Delaware.
As with every field season, IceBridge collaborated with other science teams: this year, IceBridge flew under one of ESA’s (the European Space Agency) CryoSat-2 satellite’s tracks and coordinated with a team from the British Antarctic Survey that was also conducting aerial surveys of the frozen continent.
“The British group began their campaign after we did, but targeted some of the areas we flew with a similar instrument suite. Once we process our data and they handle theirs, we’ll be able to compare our measurements and combine them to form a better picture of Antarctica,” MacGregor said. “We also flew over their on-continent bases, providing them with images of nearby areas as they prepare their operations for this field season.”
During her stay in Punta Arenas, Newman met with Chilean researchers and students to discuss future opportunities with Chile.
The mission of Operation IceBridge is to collect data on changing polar land and sea ice and maintain continuity of measurements between NASA’s Ice, Cloud, and Land Elevation Satellite (ICESat) missions.
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Credit: NASA