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Comment Re:Really ? (Score 3, Informative) 175

When quoting Arnold I have been a little incorrect, since five figures of precision in the measurement of physical variables actually give you a two months forecast. But I studied this about thirty years ago...
If you want to estimate the error, if n is the number of months of the forecast and eps is the measurement precision, the error is given by:
10^(2.5n) times epsilon. As you can see the error rapidly increases, although the formula I transcribed from Arnold's textbook is quite rough (toroidal Earth, steady flux and negligible viscosity). Not a bad approximation for estimating trade winds flux, however.
People at MET probably took care of the propagation of numerical errors in the calculation, by increasing the grid density and maybe setting up a system capable of working with quadruple precision. However the problem again is the needed precision of input data, that increases exponentially with the time forecasted.

Comment Really ? (Score 3, Informative) 175

Arnold in one of his textbooxs demonstrated that, to make a weather prediction one month in advance, you need to measure pressure, temperature, wind speed and humidity with at least five significative decimals. He used sound mathematical methods based upon a theorem by Poincaré. With all the respect for technical skills and competence of people at Met Office, I trust more what Arnold demonstrated using nothing but paper and pencil. Good math is never overcome by brute force computation.

Comment The last C64 I saw... (Score 3, Interesting) 290

...was managing the inventary of a bookstore here in Italy. I saw it about five years ago, and the bookstore was specialized in ancient books.
It was a really inspiring vision to see on the same desk a C64 surrounded by some in-folio books. Too bad that the store was shut down recently, don't know what happened to the C64.

Comment Not used here (Score 2) 279

I don't use IoT, and I will never will. No need to share with external world room temperatures, door status or garden humidity. Electromechanical devices are enough for this, they are much cheaper, and are free from the risk of being tampered from an indian hacker.
I still have to understand why people need to control everything from their smartphone, when there are simpler solutions that require much less of your precious free time to be implemented and used.

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