No, they say end-to-end, meaning they use raw obsevations. Most or all other medium-range models start with ERA5.
There's a paper from Norway that tried end-to-end, but their results were not spectacular. That's the aim of many though, including ECMWF. Note that ECMWF already has their AIFS in production, so AI weather prediction is pretty mainstream nowadays.
Google has a local nowcast model that uses raw observations, in production, but that's a different genre of forecasting than the medium-range models of Aardvark.
> Google has a local nowcast model that uses raw observations, in production, but that's a different genre of forecasting than the medium-range models of Aardvark.
It's very clear from the MetNet announcement blog[1] that they require HRRR or other NWP output at runtime.
There is already a lot of real value in scientific ___domain-specific models. One such example is weather forecasting. We can suddenly create forecasts with astonishing accuracy on commodity hardware in a matter of seconds, versus several hours with traditional numeric models. This is life-saving.
