51B-147-31 (Linhof 250 mm)
Flight 51B; 34.1N, 120.2W, 3 May 1985
A mixture of prevailing winds and a local Santa Ana (downslope katabatic wind) created patterns on the sea surface off Point Conception and in the Santa Barbara Channel, California, as the Challenger moved over the coast in the springtime. The prevailing northwest wind was blowing briskly enough to form wind slicks (Langmuir cells) along with whitecaps on the offshore sea surface. These same northwesterly winds produced an atmospheric wake behind small San Miguel Island that finally merged into a cross-hatched layer of stratus cloud well south of the Channel Islands. These winds aided in creating the turbulent ocean wake behind Santa Cruz Island, just east of San Miguel.
Imposed on the prevailing winds was a local downslope Santa Ana flow of air developed as the result of a high-pressure system in the atmosphere lying over eastern California and Nevada. That wind, blowing from the north, caused the cross-hatching on the sea surface barely visible south of Point Conception and in the stratus clouds lying over the water south of the Channel Islands, and the blue "wind shadows" off the coast of Santa Barbara. Such a mixture of winds is not uncommon along this part of the California coast, making Vandenberg Air Force Base, seen to the north of Point Arguello, one of the windier and cooler locations along the California shore.
Download 53.tiff high resolution TIFF file (8.3 MB)