The C-130 flight track is plotted on the lower resolution GAC image because of the loss of the higher resolution HRPT image.
This was a nearly clear day. The ship radar image saw no cloud returns all afternoon. The ship lidar also showed no returns except for a small broken cloud around 0.6 km from 21:30 to 22:30 UT.
The larger view shows a large surface high east of the SHEBA ship ice camp. The satellite images ( IR and 3.7 microns) show a large stratus cloud northeast of the ship. This cloud was moving toward the ship but did not get into the aircraft flight patterns. However, a few clouds in an elongated line were east and south of the ship during the flights. They are visible on the C-130 flight track image.
The trajectories to SHEBA ship show the air at all levels came from the local region of the arctic around the large high pressure system. The lower level air, surface to 1.5 km came from the Beaufort Sea to the east while the higher levels, 3.0 and 6.0 km, came from the Arctic Ocean just west of SHEBA ship. Only the 9.0 km trajectory has its root outside of the Arctic Ocean back in Siberia.
The trajectories to Barrow show the low level air, surface to 1.5 km, came from the east, northern Canada, across the Beaufort Sea. The 3.0 km trajectory shows air coming only from Northern Canada. The high level trajectories at 6 and 9 km show North Pacific air rotating around the Aleutian low and then flowing north across Alaska to reach Barrow.
