The AIFS has been developed with Anemoi, an award-winning, open-source framework which has been co-developed by ECMWF and national meteorological services across Europe.
Users can generate forecasts with the AIFS by using the anemoi-inference package with ECMWF open data.
The notebooks below demonstrate how to generate forecasts using the AIFS Single and AIFS ENS models.
- Generate a deterministic forecast with AIFS Single
- Generate an ensemble forecast with AIFS ENS
Note that users will be unable to exactly reproduce an official AIFS forecast when running AIFS themselves. The results will be statistically, skilfully similar, however, they will not be bit-identical. This is due to:
- The non-determinism of GPUs
- The differing interpolation pathways of ECMWF open data (used by the community to generate an AIFS forecast) and ECMWF's operational analyses (used by ECMWF to generate an operational AIFS forecast).
- ECMWF open data are reprojected from a lat/lon (0.25°) grid to N320 for use by the AIFS.
- ECMWF's operational analyses are reprojected from an octahedral (o1280) grid to N320 for use by the AIFS.
Users with access to the MARS archive may request historical analysis data on the n320 grid, which will follow the same interpolation pathway as the operational AIFS. See MARS interpolation with MIR for more details about interpolation.