Comments on life, the universe and everything from an aging Sixties survivor.

Location: Massachusetts, United States

Ummm, isn't "about me" part of the point of the blog?

Tuesday, May 04, 2010

The mathematics of a good view

This topic crosses my mind any day that is a) unusually clear and b) I've climbed up Shittin' Hill, where one is about 60 feet above sea level. In clear weather it's possible to see well down the South Shore, subject to certain limits that I once learnt in marine piloting courses. I brushed up on the subject and I've been doing the math when I get some scenery.

The basic principle is to take the square root of the height of the observer's eye, and add that to the square root of the height of the observed object. The sum is equal to the distance in statute miles from which an observer at that height can see any part of that object. If one wants to get nautical about it, one then multiplies the sum by 1.15 to get the distance in nautical miles. Piece of cake with a calculator.

The rule is subject to certain variables. Because the earth is curved (contrary opinions are disallowed for lack of evidence), you can't see all of the observed object unless you're relatively close to it. That's one variable. Another is weather. In these parts, one can count on "unlimited visibility" (greater than five to seven miles) maybe one day in five. A third is "loom," the phenomenon that creates mirages, and at times can increase the range of visibility. The observer doesn't actually see the object in these cases, but an image or reflection of the object.

There is one more, one that the authorities on this business often overlook, and that is the mass of the observed object. If one is looking for a landmark at a distance of, say, 25 miles, it is easier to spot a skyscraper than a communications tower of the same height, and still easier to spot a hill of that height than the skyscraper.

All this bears upon the nervous angst of the privileged of Cape Cod, Martha's Vineyard and Nantucket regarding the Cape Wind proposal. Similarly, it bears upon the stupidity with which Cape Wind has responded to nimby media manipulation. The privileged, many of whom know the mathematics of finding objects at a distance over the water, have deliberately manipulated the evidence in their favour. Cape Wind, having finally come up with a density proposal that works out to around 5.5 per square mile, obstinately publishes pictures of European wind farms with many times this density, which the nimbies manipulate with great delight. These images also feature unlimited visibility. But Nantucket Sound's definition of unlimited visibility is often that you can see someone else's hand in front of their face.

So, having noted today that I can just see tall slim white objects on hilltops ten miles off, without being able to tell if they're cell phone towers, wind generators, or Slovenian basketball players, I'm inclined to wait before I throw my hissy fit. In any case, I'd rather look at a wind farm than an oil spill.


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