Welcoming a New Instrument for ‘Probing’ the Polar Regions
In 2009 it was just a dream. But creative vision, sweat equity, good partnerships and funding can bring dreams to reality, and 2013 delivered.
It was four years ago that a small team of Lamont scientists, Polar Geophysicist Robin Bell, Engineer Nick Frearson and Ocean Climate Physicist Chris Zappa, began discussions of an instrument that could be used to collect measurements on polar ice during routine field-support flights in both the Arctic and Antarctic. Named the IcePod, it would fit onto the LC130 aircraft, a massive four-engine turboprop plane that is the workhorse of the U.S. polar support services. The pod design focused on a 9 foot long cylindrical “boot” that would hold a range of instruments and gather data on ice conditions as the aircraft carried out its seasonal polar mission. The pod would be removable, fitting in the rear paratroop door, and modular allowing for a range of instruments and ultimate utility.
Funding came through special Recovery Act Funding of a National Science Foundation Major Research Instrumentation grant. NSF saw this as an opportunity for the full science community to increase data collection and understanding of polar ice conditions, yet with a significant reduction in the logistical support needed.
The polar flights for the LC130 are coordinated through NSF but flown by the New York Air National Guard, requiring close planning and coordination with both groups as the Icepod was developed. Any design would need to meet full air safety standards, cause limited drag on the aircraft and be easily mounted or removed by the air-crew as needed.
The instruments housed in and around the pod would need to be insulated from any interference with the plane and its equipment. Additionally as the pod arm is extended below the aircraft, the instruments would need to be tightly sealed for temperature control and able to pass intense turbulence testing. Calling up visions of the electromagnetic shrinking machine from “Honey I shrunk the kids,” an additional challenge was the need to fit the instruments in the small interior cubicles of the pod. Instruments and equipment were compacted and streamlined.
The starting line up of instruments:
Radar (RAdio Detection And Ranging) uses radio waves to image through the ice. In order to collect both deep and shallow ice information Icepod will carry two types of radar. Deep-Ice Radar (DICE) is a blade antenna resembling black shark fins designed to collect data thorough more than 4 km (resolution of 10 m). The DICE radar antenna will work over the deep interior of the ice sheets to measure ice thickness and bed wetness where water may be lubricating the base of the ice sheet and changing conditions. The Shallow-Ice radar (SIR) is a horn antenna for penetrating closer to the surface of the icesheet, through approximately 300 meters of snow (25 cm resolution). SIR focuses on recent processes in the snow/ice system, looking at annual rates of snow accumulation and the layer of snow (firn layer) not yet compressed into glacial ice, estimated to range in depth from 40-100 m below the surface.
Optics: Laser, is an instrument that uses light to image and collect data on surface elevation and snow texture. Two different cameras will be used to collect data on reflectivity and temperature (visible-wave and infrared cameras). As we layer together all the information collected from the instruments we can integrate our understanding of the ice conditions at the base of the ice sheet up through the internal ice layers, to the ice sheet surface, and up to the reflective return from the ice.
Next week the Lamont’s Polar Geophysics Team will fly with the New York Air National Guard, bringing the long envisioned IcePod into the air for field-testing. The team is excited to take to the skies to see what the instruments can do, although with the first battery of tests flown close to home in upstate New York, not all the instruments can be performance tested. If all goes well and the go-aheads are received, a trip to Greenland is planned for later in the spring to allow full instrument testing in true polar conditions.
To learn more about the Icepod project see: http://www.ldeo.columbia.edu/icepod/
For more on the Polar Geophysics Group: http://www.ldeo.columbia.edu/polar-geophysics-group/
Funding for this project from #ANT 0958658 under the MRI initiative.