About Skin surface temperature

[christianbsch]

Dear CCPP team,

I would like to inquire about how surface temperature (which is set as input in the forcing data) is used in the calculation of skin surface temperature in the CCPP SCM model (using GFSv16 physics suite). I would appreciate a more detailed explanation of these concepts within the context of the model.

Thank you for your time and any information you can provide.

Best regards,

Christian

[hertneky]

@christianbsch Yes, surface temperature (T_surf) in the SCM is read in from the case data file and interpolated in space and/or time. Skin temperature can also be input from the case data file, but only when using model_ics or lsm_ics, for example when using the case_generation capability. In the SCM, the skin temperature is associated with surface temperature (when not using model_ics, lsm_ics or prescribing surface fluxes), meaning changes in skin temperature through physics can update the SCM state temperature. Any updates to the skin temperature are done in the CCPP physics and I don't know enough about the physics to further answer your question.
@grantfirl @dustinswales may have additional information they can contribute.