IceBridge continued its field campaign with surveys of northern Greenland's ice, flights along paths measured by satellites and a line connecting several ice core drilling sites, and completed the season's last remaining top priority mission.
On Apr. 30, IceBridge researchers boarded the P-3 research aircraft for a grid survey of northeast Greenland, but returned to Thule about an hour after takeoff as a safety precaution to address a minor issue with the P-3 aircraft.
Early the next morning, May 1, the part needed to repair the P-3 arrived on the rotator, a regularly scheduled flight between Baltimore-Washington International Airport and Thule Air Base that ferries equipment, supplies and personnel back and forth to Greenland. Within two hours of the rotator touching down NASA aircraft technicians completed repairs and the P-3 was ready to take off.
Researchers collected data between Thule Air Base and Camp Century along a portion of the Greenland Inland Traverse, or GrIT, line. GrIT is a joint effort to move equipment over the ice surface from Thule to inland research stations. The P-3 also overflew a field research site.
On the morning of May 2, the IceBridge team looked at the weather and headed out for a newly designed mission that measured paths surveyed by NASA's ICESat and the European Space Agency's CryoSat-2 satellites and took measurements at an ICESat calibration site near Summit Station. The P-3 surveyed the CryoSat-2 ground track a day before the spacecraft was scheduled to pass overhead and flew at a higher altitude than usual, widening instrument survey swaths to better match the measurements taken by ESA's ice-monitoring satellite. Flying over satellite ground tracks gives researchers data useful for verifying spaceborne measurements.
This survey also followed a line connecting the GRIP, NGRIP, NEEM and Camp Century deep ice core drilling sites. Ice penetrating radar data on this line gives researchers insight into internal layers in the ice sheet, potentially allowing them to connect ice core layers between the various sites.
The following Monday, May 5, IceBridge returned to the air with the mission's last remaining baseline flight, a survey of planned ICESat-2 ground tracks. Baseline surveys are the highest priority flights of the campaign and focus on the most rapidly changing areas of Greenland.
The P-3 overflew several future ICESat-2 lines covering a variety of areas near Thule Air Base. Because ICESat-2's laser altimeter will have three beam pairs, this survey was designed to sample at least one of each pair. In addition, the P-3 measured the flowline of Petermann Glacier and flew over surface research sites near Thule.