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Google says AI weather model masters 15-day forecast

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Re: Google says AI weather model masters 15-day forecast

#51
post #33
post #13

Earlier quoted context omitted.

whelp... Ok, how would you articulate an understanding of how the weather works? Let's face it, it's not going to be easy to frame in natural language...

You can take a meteorology course that explains how the weather works. That course is the articulation.

That’s great but it’s not going to scale to the level of detail that makes this better than traditional meterologist models

Re: Google says AI weather model masters 15-day forecast

#52
post #18

Earlier quoted context omitted.

>Great, so it's using historical data to make a prediction about what has already happened. That's ok though because it doesn't know it's acting on old data. Researchers would give it data and ask for the 15 day forecast, the researchers then compare against that real world data. And as noted, "it surpassed the centres forecast in more than 97 percent" of those tests. This is all referred to as backtesting.

It's still not as good as actually new data. The individual model may not overfit the existing data, but the whole system of researchers trying lots of models, choosing the best ones, trying different hyperparameters etc. easily can.

In principle they trained on data up to 2017, validated (tried different hyper parameters) on data from 2018, and published results on data from 2019...

Re: Google says AI weather model masters 15-day forecast

#53
post #47

Earlier quoted context omitted.

It's still not as good as actually new data. The individual model may not overfit the existing data, but the whole system of researchers trying lots of models, choosing the best ones, trying different hyperparameters etc. easily can.

yeah, but weather patterns data isn't different now than 10 years ago, right? right? ...

Overfitting is always bad by definition. The model learns meaningless noise that happens to help getting good results when applied to old data (be it due to trained weights, hyperparameters, whatever) but doesn't help at all on new data.

Re: Google says AI weather model masters 15-day forecast

#54
post #48
post #18

Earlier quoted context omitted.

>Great, so it's using historical data to make a prediction about what has already happened. That's ok though because it doesn't know it's acting on old data. Researchers would give it data and ask for the 15 day forecast, the researchers then compare against that real world data. And as noted, "it surpassed the centres forecast in more than 97 percent" of those tests. This is all referred to as backtesting.

I wish these sort of papers would focus more on the 3 percent that it got wrong. Is it wrong by saying that a day would have a slight drizzle but it was actually sunny all day, or was it wrong by missing a catastrophic rain storm that devastated a region? I've worked on several projects trying to use AI to model various CFD calculations. We could trivially get 90+ percent accuracy on a bunch of metrics, the problem i…

Yep, this is also the problem that self-driving cars have with the "accidents per mile" metric.

Re: Google says AI weather model masters 15-day forecast

#55
post #46
post #7

This is great from a practical standpoint (being able to predict weather), but does it actually improve our understanding of the weather, or WHY those predictions are better? That is my issue with some of these AI advances. With these, we won't have actually gotten better at understanding the weather patterns, since it's all just a bunch of weights which nobody really understands.

We can work backwards from correct predictions and develop an understanding that way. But most people just need to know if it’s going to be storming, hot or, going to rain on a given day and that is where this shines.

We can always work backwards, regardless of AI.

Re: Google says AI weather model masters 15-day forecast

#56
I'm friends with a meteorologist and the 15+ day forecast is the bane of their existence because you can't accurately forecast beyond a week so I would love to know how they are measuring accuracy. The article doesn't say and I know the paper is going to go over my head.

Re: Google says AI weather model masters 15-day forecast

#57

I'm friends with a meteorologist and the 15+ day forecast is the bane of their existence because you can't accurately forecast beyond a week so I would love to know how they are measuring accuracy. The article doesn't say and I know the paper is going to go over my head.

I would guess that everyday they're comparing the current weather against the forecast from 15 days ago. Not a lot of data points to be sure, but perhaps enough to have confidence of very high accuracy.

Re: Google says AI weather model masters 15-day forecast

#58
post #46

Earlier quoted context omitted.

We can work backwards from correct predictions and develop an understanding that way. But most people just need to know if it’s going to be storming, hot or, going to rain on a given day and that is where this shines.

We can always work backwards, regardless of AI.

[deleted]

Re: Google says AI weather model masters 15-day forecast

#60
post #46

Earlier quoted context omitted.

We can work backwards from correct predictions and develop an understanding that way. But most people just need to know if it’s going to be storming, hot or, going to rain on a given day and that is where this shines.

We can always work backwards, regardless of AI.

Sure, but with this new predictive model we will have better predictions to work backwards from.

OC was saying (I’m going to paraphrase) that this is the death of understanding in meteorology, but it’s not because we can always work backwards from accurate predictions.

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