Difference between UM ainitial and astart?

Dear NCAS helpdesk,

Can I clarify - for HadGEM3 suites like u-as037, what’s the difference between um > model input and output > dumping and meaning > astart (Reconfiguration output/atmosphere input dump) and um > reconfiguration and ancillary control > general technical options > ainitial (Input dump location)?
Which is the correct place to specify the atmosphere start dump? And if they are both set to different file locations, does one override the other?


Best wishes,


Hi Rachel,

ainitial is the location of the input dump for the reconfiguration, if running the reconfiguration.

astart is the location of the reconfiguration output dump, if running the reconfiguration, and the input dump to the model.

You can access further help, for a variable, in the rose edit GUI by clicking on the cog to the right of a variable and selecting “help”.


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