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Comment by timthorn | Hacker News Reader

Lewis Fry Richardson was the person who first attempted numerical modelling of the weather. He spent his free time on the front line of WWI as an ambulance driver trying to complete a single 6 hour forecast. Unfortunately his source data was noisy and ruined the result, but it was his efforts that enabled computer generated weather forecasts - he wasn't a bit player.

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I believe the problem was his numerical method was unstable, and blew up.

Somewhere in this talk by Philip Roe https://youtube.com/watch?v=uaH91P665PI

I understand that his method was rerun by the Met Office and when they excluded the bad source data they got the correct answer.

https://www.metoffice.gov.uk/about-us/who/our-history/celebr...

  limitations with the data
  method was eventually... proved correct

Does sound like they're blaming the data; though his "method" could well refer to his general method, not to every exact detail.

Philip Roe is himself a famous pioneer in CFD, so I lean towards trusting his version more... he said the forecast was of extraordinary 100mph winds, pretty specific. The bad data would have to be wildly bad to yield that! OTOH it inevitably happens with instability.

However, I really don't know. Maybe it's become a folktale, to illustrate instability, since it's a big deal in CFD!

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