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Answer to question 3

satellite image: Strait of Georgia, SEASAT / SAR

satellite image: Strait of Georgia, SEASAT / SAR

Larger image

The areas of water in this image are mostly a speckled grey tone, but with large sections of black. These black areas are:

  1. Oil slicks on the water surface.
  2. Shadows from the hills on the islands.
  3. Wind sheltering by the land areas.

The answer is C.

A. No.

It would take an extraordinary amount of oil and an incredible current and wave action to distribute oil among all those islands in the pattern seen here.

B. No.

There is no evidence of very tall hills on the islands. The incidence angle from the satellite would not be blocked to that extent by even very tall hills or mountains. The shape of the black water areas do not conform to prospective hills on the islands.

C. Yes.

The brighter areas of water are due to wind-generated waves which cause a brighter radar reflection. Where the land shelters the water surface from wind, the lesser wind speed reduces the magnitude of the waves and the water surface acts like a mirror, reflecting the radar beam in a specular manner - away from the radar antenna. This appears as areas of little or no radar return on the image: a black tone.

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