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Computational Grids

From Turing’s Cathedral (pg 172-3), describing a giant lattice covering the entire surface of the Earth:

If Laplace’s mathematical intelligence were replaced by a computing machine of unlimited speed and capacity, and if the atmosphere below 100km were spanned by a computational lattice whose mesh size were less than the scale of the smallest turbulent eddy, say one millimeter… [all predictions would prove inaccurate after one month] not because of quantum indeterminacy, or even because of macroscopic errors of observation, but because the errors introduced into the smallest turbulent eddies by random fluctuations on the scale of the mean free path (ca 10-5mm at sea level), although very small initally, would grow exponentially… The error progresses from 1mm to 10km in less than one day, and from 100km to the planetary scale in a week or two.

Jule Charney and Walter Munk’s paper presented at the Conference on the Computer and the Development of Science and Learning, Institute for Advanced Study June 6 to June 8, 1972 (sadly, I couldn’t find a text for the paper online – for a full reference, see MIT’s archive).

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Biological Supercomputer

From George Dyson’s Turing’s Cathedral, relaying meteorologist/mathematician Lewis Fry Richardson’s description of a compound dedicated to the prediction of weather:

“After the war, Richardson published a detailed report, Weather Prediction by Numerical Process… At the end of his account, he envisioned partitioning the earth’s surface into 3,200 meteorological cells, relaying current observations by telegraph to the arched galleries and sunken amphitheater of a great hall, where some 64,000 human computers [people making calculations by hand] would continuously evaluate the equations governing each cell’s relations with its immediate neighbors, maintaining a numerical model of the atmosphere in real time.”

For some reason I imagine a giant geodesic dome with mountains in the background (the Banyan Bowl above is the closest approximation I could find).