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In the standard OpenIFS model the source code for atmospheric composition (atmospheric chemistry and aerosol code) has been replaced by dummy routines. The additional model sources for OpenIFS/AC replace these dummy routines and substitute the full composition source code. It is therefore necessary to rebuild the binary model executable after adding the additional model source code. This process is described further below.
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You can either convert your existing OpenIFS installation or create a new installation for OpenIFS/AC. We recommend the latter and in this case to create a new installation and for this you will also need the sources for of the standard OpenIFS model (oifs43r3v2) which can also be found on the ftp server.
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