Tall objects create wind shadows.  I seem to recall a ratio of 11 to 1, meaning a 100‘ object has a  wind shadow out to 1100’.   But the above photo from NASA’s Earth Observatory site of Chile’s Juan Fernandez Islands--of Robinson Crusoe fame--show disturbances of wind, if not complete shadows, that reach out a remarkable and instructive175 miles and ratios of between 175 to 266 to 1.      

        Approaching a high island from directly downwind is a bad idea from much farther out than I ever expected  

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        I feel sorry for my right eye, which I have come to think of as a small, innocent, trusting creature, perhaps furry and living beneath the ground, who every time he thinks it safe to stick his nose out, gets whacked.     The most recent whacking yesterday was without complications.  Today as expected the poor eye is swollen shut.  I look as though I have been in a bar fight, unbecoming at any age, but particularly mine.  There is no such thing as minor surgery.  Just surgery, and worse surgery.

        For the record I never have been in a bar fight; but then I seldom drink in bars.

        I may be able to make plans next week.