3 ms·
is it possible to self-correct, looking at initial value errors in the past? Is it too hard to prescribe the error in the initial value?
by willsmith72 3y ago
is it possible to self-correct, looking at initial value errors in the past? Is it too hard to prescribe the error in the initial value?
- counters 3y agoYes, this is effectively what 4DVar data assimilation is [1]. But it's very, very expensive to continually run new forecasts with re-assimilated state estimates. Actually, one of the _biggest_ impacts that models like GraphCast might have is providing a way to do exactly this - rapidly re-running the forecast in response to updated initial conditions. By tracking changes in the model evolution over subsequent re-initializations like this, one could might be able to better quantify expected forecast uncertainty, even moreso than just by running large ensembles. Expect lots of R&D in this area over the next two years... [1]: https://www.ecmwf.int/en/about/media-centre/news/2022/25-years-4d-var-how-machine-learning-can-improve-use-observations https://www.ecmwf.int/en/about/media-centre/news/2022/25-yea...