Page History

...

Making a forecast with AI is very efficient.  It requires only a single Graphics Processing Unit (GPU), takes less than a minute to run, and consumes a tiny fraction of the energy required for an IFS forecast.  This brings the prospect of more frequent and/or quite large ensembles of AI forecasts.

Points to consider when using AIFS output

In addition to points for consideration outlined in the AIFS single section

...

• High-quality ensemble forecasts that outperform ECMWF’s traditional physics-based ensemble system in medium-range forecasts on most accuracy and reliability scores.
• Very fast and economical to produce a forecast sequence.
• The principle for construction of meteograms and charts is very similar to that used by IFS ensembles.
• Individual ensemble members do not exhibit the smoothing seen in AIFS-SIngle and have similar levels of forecast activity to IFS.  This is because the CRPS loss function does not encourage smoothing.
• AIFS-ENS control verifies better than AIFS-ENS members (possibly with 6-12h gain).
• Are currently little bit over-dispersive.
• Very small totals can appear in the precipitation fields far too often.  This will be fixed in upcoming cycles.
• Physical consistency in the output is unlikely to be as good as with IFS.  This is being investigated.
• Cloud fields appear very "blocky" after T+0.  This is being investigated.

Practical use of AIFS output

Forecasters should consider:

...