A large surface high pressure system occupied all of the Beaufort Sea. It was centered northeast of SHEBA ship. A low was centered in the Bering Sea off the southwest coast of Alaska. Barrow was about half way between these two systems.
Clouds were very thin over Barrow. Some cirrus could be seen to the southwest. Immediately north of Barrow, mostly light boundary layer stratus clouds appeared which were thin enough so that patterns in the ice could be seen through them on the visible satellite images. The 3.7 micron images shows two large white patches northwest of Barrow. These areas are nearly clear of boundary layer clouds. The darker areas around them are the boundary layer clouds which are radiatively warmer than the surface because of the temperature inversion. They also reflect some solar radiation which make them appear darker on the 3.7 micron image which is a negative image of the energy detected by the satellite. The white patches are colder and less reflective that the surrounding boundary layer clouds.
The trajectories to SHEBA ship show most of the air coming from near the ship in the Chukchi Sea. Only the 6 and 9 km trajectories reach farther south spiraling north from the lower Chukchi Sea.
The trajectories to Barrow show the low level air, surface to 1.5 km, came from the Beaufort Sea to the northeast. The higher levels, 3, 6, and 9 km, air came from the north near the pole after circling around the high pressure system.
