Images are mapped to a simple rectangular grid, so each pixel represents a constant area in degrees longitude and latitude. The images begin in the northwest corner and are stored top down. Element (1,1) is the north west corner, element (1,512) is the north east corner, element (512,1) is south west and (512,512) is south east.
There are usually 2 AVHRR satellites passing over the west coast of N. America, making available 2 - 4 images per day for any given area. After July 1, 2005, more than 3-4 images may be present since any data capture with data in the area of interest is included.
For the old-style EBC California current images described under 3., only images which were judged to contain useful cloud-free areas are archived; rarely do all images from a given day meet this criterion.
For images dated earler than July 1, 2005: When the coast is visible, Ocean Imaging is supposed to be correcting the navigation to within 1 pixel using known coastal points, although some of the images have larger errors. These are often cloudy or foggy near the coast, making an exact determination of the coast location difficult.
BCO-DMO Blog
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