Hi Ella,
There is a bit of logic in the job script which sets the nodust
optional configuration based on the date:
cylc__job__inst__env_script() {
# ENV-SCRIPT:
eval $(rose task-env)
DUST_OPT=
EC_OPT=
DATE=$(rose date -c -f %Y%m%d%H%M)
if [[ $DATE -lt 201107201200 ]]; then
DUST_OPT=nodust
fi
}
This is pulled in from the file suite-runtime/dm.rc
in the suite.
The logic seems to be that there is no dust in UM start dumps before this date (I found a reference to this in the suite repo: https://code.metoffice.gov.uk/trac/roses-u/changeset/7458)
However looks like you are starting from an ERA file anyway, so that logic isn’t relevant.
Hopefully that explains what is going on with the different behaviour based on the start dates.
Annette