Coupling of GOCART aerosols with radiation

[ChunxiZhang-NOAA]

Description

GOCART aerosols can be coupled with the radiation scheme. This is a new feature. Without coupling the radiation scheme uses MERRA2 climatological data. The detailed description of this new feature can be found here
gocart_rad_coupling.pptx

[yangfanglin]

More development work is required in the following areas as a few of us discussed in email communications.

1. Add a namelist parameter to control the use of either GOCART or MERRA2 clim aerosols for radiation, instead of hardwiring to GOCART aerosols when GOCART is active.

2. Add and/or use existing code to automatically detect the location of GOCART aerosol tracers defined in the field_table for aerosol-radiation coupling, instead of hardwiring the tracer position number that only works for a particular field_table.

3. investigate how to include radiative effect of stratospheric background aerosols, primarily sulfate from volcanic eruptions, in retrospective and real-time forecasts when GOCART is active.

@bbakernoaa @rmontuoro @AnningCheng-NOAA @ChunxiZhang-NOAA and Kate Zhang, Please feel free to update.

[AnningCheng-NOAA]

1. can be achieved using iaer, planning to use iaer=2011 for coupling gocart with radiation. iaer=1011 or 5111, for example, are for gocart uncoupled with radiation.
2. [aer_nm] [aerfld] etc.:
   standard_name = mass_number_concentration_of_aerosol_from_gocart_climatology should be changed to mass_mixing_ratio_aerosol_from_gocart_or_MERRA2_climatology. The unit should be kg/kg instead of /kg.

[ligiabernardet]

Is this needed for UFS prototype p8?

[yangfanglin]

@ligiabernardet per the plan Avichal gave at today's coupled model meeting, p8 will not include GOCART aerosol component. p8.1 will be dedicated to experimenting with aerosols. Whether or not to turn on the interaction in pr8.1 of GOCART aerosols with radiation described in this PR depends on if the wet decomposition issue can be resolved when p8.1 starts.

[dustinswales]

@ChunxiZhang-NOAA
This appears to be resolved with 910 Can we close this issue?

[ChunxiZhang-NOAA]

@dustinswales Yes, please close this issue.