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GraphCast: AI model for weather forecasting

deepmind.google

81–90 of 310 posts

Re: GraphCast: AI model for weather forecasting

#81
post #53

Earlier quoted context omitted.

I don't understand why this is downvoted. This is a classic thing to do with deep learning: take something that has a solution that is expensive to compute, and then train a deep learning model from that. And along the way, your model might yield improvements, too, and you can layer in additional features, interpolate at finer-grained resolution, etc. If nothing else, the forward pass in a deep learning model is almo…

> the forward pass in a deep learning model is almost certainly way faster than simulating the next step in a numerical simulation Is this the case in most of such refinements (architecture wise)?

Practically speaking yes. You'd not likely build a statistical model when you could build a good simulation of the underlying process if the simulation was already really fast and accurate.

Re: GraphCast: AI model for weather forecasting

#82

> GraphCast makes forecasts at the high resolution of 0.25 degrees longitude/latitude (28km x 28km at the equator). Any way to run this at even higher resolution, like 1 km? Could this resolve terrain forced effects like lenticular clouds on mountain tops?

One big problem is input weather data. It's resolution is poor.

Yeah, not to mention trying to validate results. Unless we grid install weather stations every 200 m on a mountain top...

Re: GraphCast: AI model for weather forecasting

#85
post #83

Curious. How can AI/ML perform on a problem that is, as far as I understand, inherently chaotic / unpredictable ? It sounds like a fundamental contradiction to me.

Weather isn’t fundamentally unpredictable. We predict weather with a fairly high degree of accuracy (for most practical uses), and the accuracy getting better all the time.

https://scijinks.gov/forecast-reliability

Re: GraphCast: AI model for weather forecasting

#86
post #83

Curious. How can AI/ML perform on a problem that is, as far as I understand, inherently chaotic / unpredictable ? It sounds like a fundamental contradiction to me.

IMO a chaotic system will not allow for long-term forecast, but if there is any type of pattern to recognize (and I would assume there are plenty), an AI/ML model should be able to create short-term prediction with high accuracy.

Re: GraphCast: AI model for weather forecasting

#87
post #83

Curious. How can AI/ML perform on a problem that is, as far as I understand, inherently chaotic / unpredictable ? It sounds like a fundamental contradiction to me.

Yes. Very accurate as long as you don’t need to predict the unpredictable. So it’s useless.

Edit: I do see a benefit to the idea if you compare it to the Chaos Theorists “gaining intuition” about systems.

Re: GraphCast: AI model for weather forecasting

#88
post #86
post #83

Curious. How can AI/ML perform on a problem that is, as far as I understand, inherently chaotic / unpredictable ? It sounds like a fundamental contradiction to me.

IMO a chaotic system will not allow for long-term forecast, but if there is any type of pattern to recognize (and I would assume there are plenty), an AI/ML model should be able to create short-term prediction with high accuracy.

Not an expert, but "Up to 10 days in advance" sounds like long-term to me ?

Re: GraphCast: AI model for weather forecasting

#89
post #86
post #83

Curious. How can AI/ML perform on a problem that is, as far as I understand, inherently chaotic / unpredictable ? It sounds like a fundamental contradiction to me.

IMO a chaotic system will not allow for long-term forecast, but if there is any type of pattern to recognize (and I would assume there are plenty), an AI/ML model should be able to create short-term prediction with high accuracy.

But AI/ML models require good data and the issue with chaotic systems like weather is that we don’t have good enough data.

Re: GraphCast: AI model for weather forecasting

#90

Does anybody know if its possible to initialize the model using GFS initial conditions used for the GFS HRES model? If so, where can I find this file and how can I use it? Any help would be greatly appreciated!

You can try, but other models in this class have struggled when initialized using model states pulled from other analysis systems.

ECMWF publishes a tool that can help bootstrap simple inference runs with different AI models [1] (they have plugins for several). You could write a tool that re-maps a GDAS analysis to "look like" ERA-5 or IFS analysis, and then try feeding it into GraphCast. But YMMV if the integration is stable or not - models like PanguWx do not work off-the-shelf with this approach.

[1]: https://github.com/ecmwf-lab/ai-models

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