explore fractional cloud selection on fractional aerosol impact

[BenjaminTJohnson]

In #117, we found that the choice of cloud fraction has an impact on the aerosol-modified radiances as well. This isn't desirable behavior. The purpose of this issue is to verify that the aerosol radiances are still influenced, even for very low cloud content (i.e., where clouds would not dominate the radiances), and to verify that this impacts visible and infrared radiances.

Test 1: tiny cloud water content values for various/tiny cloud fractions, looking at whether aerosol-dominated radiances are influenced by the choice of cloud fraction.

Feel free to provide results of additional tests here.

[chengdang]

Updates:
Currently, it seems there are no existing geovals contain both cloud and aerosol information in JEDI.
The test will for now adopt the simplified sample profiles in CRTM unit tests.

[BenjaminTJohnson]

@chengdang this is strange, right? There's almost always aerosols and clouds together in reality.

@gthompsnJCSDA @jeromebarre Greg/Jerome, would like to get your quick input on the observation that Cheng has made that there's no geovals that contain both clouds and aerosols - any thoughts?

[jeromebarre]

What are the geovals, where do they come from?

[chengdang]

NOTE: it is important to note that the cloud content of these tests are constant, which is a wrong approach to set up this test.
Keeping these figures for future references only, the results do not represent the test results of this issue.

Tests for two sample profiles (top/bottom), color/numbers are cloud cover fraction:

Brightness temperature

Radiance

[chengdang]

What are the geovals, where do they come from?

It's the modeled state variables right? @jeromebarre

[jeromebarre]

I meant where as skylab or input data of ctest or else? What instrument product footprint? etc etc

[BenjaminTJohnson]

closing this issue. After rigorous testing, compensating for the change in cloud water content with changes in cloud_fraction, I find that there's no cloud fraction influence on the aerosol-impacted radiances.