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This folder serves as a staging area for the initial and boundary conditions data and if the target files in $AC_IC_DIR already exist then they they will not be overwritten.
Creating initial conditions at the end of an experiment run
When setting LAC4IC=true an AC-for-IC grib file is created at the end of a run. It is a snapshot of all chemical/atmospheric composition tracers. This file can be used by the pre-processing script (prep script) to create new initial conditions.
With the AC-for-IC file, initial conditions for a new experiment can be generated which will provide a continuation of the chemical evolution of the tracer fields from the previous experiment. The meteorological fields to complement the initial conditions can originate from an archived experiment or can be generated with the OpenIFS Data Hub. This workflow is desirable when aiming to reinitialise the model integration with an updated weather forecast or analysis data (which does not provide AC tracers).
Running a forecast experiment on the ECMWF HPCF
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