CERES radiation flux problem

[xwgw]

Help Post:
I would like to know the product information of the radiative flux of the surface and the top of the atmosphere provided by the CERES Cloud and Radiation Observation system. First of all, how is the long-wave radiative flux defined and how is it calculated, because the short-wave wavelength range is 0.3 to 5 microns, the window channel is 8 to 12 microns, and so on.
How is the long wavelength range defined?
Secondly, to calculate the radiation flux information of the surface and the top of the atmosphere, is it necessary to input aerosol parameters, cloud parameter information and atmospheric parameter information, and then calculate it through the radiative transfer model? However, there are no conditions for using the aerosol parameter information in the SSF product of CERES single footprint satellite (because I read the product description before, It has been mentioned that aerosol retrieval is not recommended when the solar zenith Angle exceeds 60°), in addition to cloud parameters: How to select the cloud height, cloud droplet particles, cloud thickness, etc. (because the cloud microphysical parameters provided by CERES satellite are multi-wavelength channels, how to select them), and how to select the atmospheric parameters (ozone content is not directly provided by CERES satellite products).
I hope you can get the help of experts, thank you sincerely.

[ASDCx - mcook]

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[wfmiller]

The longwave flux is defined as 5 to 100 microns. It is obtained from the total channel filtered radiance minus the shortwave channel filtered radiance during the day. The shortwave channel is assumed to have negligible energy during the night, so the total channel filtered radiance is used for the longwave without subtracting the shortwave from it.
The SSF does contain the imager aerosol optical depths determined from clear pixel on the SSF when available. The day time solar zenith angle is less than 60 degrees at mid- and tropical latitudes during the day time pass. Depending on what aerosol information you need, the SYN1deg-Hour and -Day has 0.55 aerosol optical depth from the Model of Atmospheric Transport and Chemistry (MATCH) which is the aerosol assimilation model used for CERES. The SYN1deg-Hour also contains the total column ozone from the assimilation. Other source include NASA Global Modeling and Assimilation Office assimilations such as Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2). Assimilations or forecast from other national modeling centers might also be available.
The atmospheric parameter information including ozone content would also need to be obtained from a modeling center such as MERRA-2 listed above. The assimilation used by CERES is not publicly available.
The SSF provides the cloud base pressure and cloud base temperature. Since you will need an atmospheric profile to do you radiative transfer, the most consistent method would to interpolate the height from the temperature profile. Other options include using the hypsometric equation to obtain the thickness and subtract it from the cloud top height. The following equations are used to obtained the cloud thickness during the retrieval process: I did locate the empirical relationship that is used to calculate cloud thickness in km used in our processing:

For water clouds with visible optical depth > 1: Cloud Thickness = 0.39 * ln(COD) - 0.1

visible optical depth <= 1: Cloud Thickness = 0.05 * SQRT(COD)

For ice clouds colder than 245 K: Cloud Thickness = 7.2 - 0.024 * Cloud Effective Temp + 0.95 * ln(COD)

The minimum cloud thickness is 0.02 km in either case.

The cloud thickness is subtracted from the cloud top height to get the cloud base.
The simplified approach would be to use the particle size and particle radius variables and not those at the 1.2 and 2.1 wavelengths. The particle size and radius can be used to calculate a consistent optical depth.