Confusion about urban downward and upwelling radiation

[Yuan Sun]

Hi all,

I am trying to understand radiative flux in CLMU and compare them with variavles from observation station such as urban plumber project.

I found that there are grid-level atmosphere variables such as SWdown (downward incident solar radiation), SWup (upwelling shortwave radiation), LWdown (downward longwave radiation), LWup (upwelling longwave radiation) but not specify in urban fraction, for example, SWdown_U, SWup_U, LWdown_U, or LWup_U.
Could I take grid-level SWdown as the atmospheric incident solar radiation in urban fractions, where downward forcing are the same in each landunits? FIRE_U as the upwelling longwave radiation in urban fractions? The upwelling shortwave radiation in urban area is equal to SWdown - FSA_U?
So my interpretation about heat flux in urban area is:
LWdown_U = LWdown
SWdown_U = SWdown
LWup_U = FIRE_U = FLDS + FIRA_U
SWup_U = SWdown - FSA_U

I am not sure if the equations are correct. Another way is to calculate, for example, LWdown_U, by column-level ouputs with TBD, HD, and MD pct_urban fraction weighted.

Thank you very much for any comments.
Best,
Yuan

 

[oleson]

Yes, your interpretation is correct:

LWdown_U = LWdown
SWdown_U = SWdown
LWup_U = FIRE_U = FLDS + FIRA_U
SWup_U = SWdown - FSA_U