I am working on solar data retrieval for Indian region using WRF-NMM model. I have done sensitivity tests by changing ra_lw_physics and ra_sw_physics. I finalized with one of the best set of it. My problem is, I have found GHI values are more or less fine but DNI values showing over estimation values. Can you please tell me, other than the two models of radiation physics, what physics will have an effect on the solar radiation variables. Once I know this then I can easily find the best fit of physics schemes for testing solar data.
If GHI is OK and DNI is not, the problem might be in the aerosol content. Note that aerosols affect the partition between direct and diffuse radiation, but do not affect so much global irradiance. Of course, the problem might also be in the parameterizations used within WRF, and/or in the partitioning of global into diffuse and direct components.
Thank you, I will try by changing various micro physics schemes and let you know the result.