Why is the Legendre expansion coefficient of phase function output from WRF-Chem only of order 2-7

[Chongz Zhang]

Dear all,
I want to use the Legendre expansion coefficient of phase function output from WRF-Chem.

However, I found that there is only order 2-7 in the file registry.chem. How can I output the first order of the Legendre expansion coefficient of phase function?

Thank you !

 

[jordanschnell]

Hi,

From what I can see, the first order is not calculated (see subroutine mieaer in chem/module_optical_averaging.F). I am not familiar with these coefficients, but given that the first order is not computed, is it possible that it is a constant or some other identity such that it can be determined offline?

Jordan