GLDAS script check for spinup time

[CatherineThomas-NOAA]

The current JGDAS_ATMOS_GLDAS job script checks if the current cycle is within a certain timeframe of SDATE and skips gldas if it is:

xtime=$((gldas_spinup_hours+12))
if [ $CDATE -le $($NDATE +$xtime $SDATE) ]; then
    echo "GLDAS needs fluxes as forcing from cycles in previous $xtime hours"
    echo "starting from $SDATE. This gldas cycle is skipped"
    exit 0
fi

The first cycles get skipped even if the needed flux files are available. This can become problematic, for example if you are trying to reproduce operations.

It would be helpful if this check could see if the needed flux files are available and run gldas if they are, even if it is within ($gldas_spinup_hours+12) hours of SDATE.