• FlihpFlorp@lemm.ee
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    5 months ago

    Somewhat off topic but just some trivia from a geology weather class I took

    100 year flood does not mean it happens every 100 years but there’s a 1/100 chance for it to happen annually

    Putting climate change aside for a second for consistency sake, you could go for 150 or 200 years without a 100 year flood or on the other side only a 5 year gap for that 100 year flood if you’re unlucky

    • Rhaedas@fedia.io
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      5 months ago

      That’s correct, it’s about probability based on past known history. An area could get unlucky and have repeat conditions sooner than normal. When many areas appear to be having this same bad luck, it’s time to reevaluate the probabilities. It’s also why regular weather forecasts haven’t seemed to get things as right as they used to…using the past percent chance probabilities in a changing environment doesn’t hit as well as it used to.

      • FlihpFlorp@lemm.ee
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        5 months ago

        Thanks for the input it never crossed my mind that weather (the thing that we can only predict) changes when the past data is no longer relevant

    • Gormadt@lemmy.blahaj.zone
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      5 months ago

      And a big problem we’re having is that due to climate change those 1/100 chance events are changing for the worst.

      • FlihpFlorp@lemm.ee
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        5 months ago

        Oh 10000% it’s why I said ignoring climate change. Weather events are getting more frequent and more extreme