The National Aeronautics and Space Administration is sticking close to earth this year to understand what’s happening at the top of the world, says nunatsiaqonline.ca

Last week, NASA started up its Operation IceBridge, the third year that it’s sent up a specially-equipped, four turboprop aircraft to study changes in Arctic sea ice

“Each successive IceBridge campaign has broadened in scope,” said IceBridge project scientist Michael Studinger of Goddard Earth Sciences and Technology Center, in a recent NASA news release.

The instruments installed on the P-3B, which flies out of the Thule air base in northern Greenland, now include a magnetometer, gravimeter, airborne topographic mapper, and camera systems which can help judge the extent and depth of sea ice.

Arctic sea ice extent for February 2011 tied with February 2005 as the lowest ever recorded.

As part of the 10-week IceBridge program, the P-3B plans to survey Canadian ice caps, NASA says.

So far, it’s flown over Ellesmere Island to sample the thick multi-year ice north of the island and look at the thinner ice closer to the North Pole.

The P-3B will also fly over the Barnes and Devon ice caps in Nunavut’s High Arctic.

The aircraft is also slated to complete an overnight flight from Thule, to Fairbanks, Alaska, to survey sea ice thickness in across the Arctic Ocean.

It will also fly over the European Space Agency’s ground-based calibration sites for its ice satellite, CryoSat-2.

And measurements collected by the P-3B will add to those made by NASA’s Ice Cloud and Land Elevation Satellite (ICESat), which stopped collecting data in 2009.