A stratus cloud with a top at 1.8 km covered the SHEBA ship ice camp before the flight arrived according to the radar. This morning sounding also indicated the presence of the cloud. However, it moved out before the C-130 arrived. A thin layer of high humidity remained on the 00 UT sounding.
A thin boundary layer cloud remained as indicated by the lidar. The satellite visible image displayed with the flight tracks shows that the cloud is very thin because ice patterns can easily be seen through it.
The IR part of the flight track image also shows the cloud was slightly thicker east of the ship. This was in the up-wind direction.
The trajectories to SHEBA ship show the low level, surface-1.5 km, air coming from the east around the high in the Beaufort Sea. In higher layers, the large low pressure system in the Bering Straights dominated the air flow. The 3.0 km tractory come from the south across Alaska while higher trajectories came from the Bering sea, loop northward through the Bering Straights and westward in the Chukchi sea before reaching the ship.
The trajectories to Barrow show some simularities. The surface air came from the Beaufort Sea to the east. The 1.0 and 1.5 km tractories came from a short distance to the southeast - mainly Alaska's North Slope. The higher level air came mainly from the Pacific Ocean and Bering Sea to the south looping around the low in the Bering Straights and traveling over Alaska.
