USA: NASA deployed its newly acquired Langley’s HU-25C research airplane as part of its Operation IceBridge. IceBridge will yield an unprecedented three-dimensional view of the rapidly changing features of Arctic and Antarctic ice sheets, ice shelves and sea ice. Studies by NASA and others generally show that earth’s polar ice is shrinking as temperatures are rising globally, with many long-term climate impacts.
Onboard the HU-25C is an instrument called LVIS (Land, Vegetation, and Ice Sensor), a scanning laser altimeter. The instrument will be flown over target areas to collect data on Arctic surface topography. IceBridge will be the HU-25C’s first NASA mission, and it will play a critical role surveying sea ice near coastal areas of Greenland.
LVIS is a scanning laser altimeter, which measures the range from the instrument to a target object. It sends a laser beam at the target, and measures the time it takes for the signal to return from striking it. Knowing the precise time the laser pulse was emitted, and the time it took for the reflection to return, yields the distance.
The multi-year mission, which began in 2009, has been using airborne instruments to map Arctic and Antarctic areas once a year and is led by NASA’s Goddard Space Flight Center in Greenbelt, USA.
IceBridge flights are conducted March through May over Greenland and in October-November over Antarctica. Other smaller airborne surveys around the world are also part of the campaign.