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CAM and RRTMG long-wave schemes and GHG

This post was from a previous version of the WRF&MPAS-A Support Forum. New replies have been disabled and if you have follow up questions related to this post, then please start a new thread from the forum home page.


New member
Since my previous post is not very specific I decided to make a new one with a more detailed explanation of what I'd like to do.

In WRF we have input radiation options.
CAM Green House Gases (GHG): Provides yearly green house gases from 1765 to 2500. The option is activated by compiling WRF with the macro –DCLWRFGHG. Once compiled, CAM, RRTM and RRTMG long-wave schemes will read these time-varying GHG from a table (annual global means).
FOR CMIP5, three GHG scenario tables are supplied with the WRF source-code:
CAMtr_volume_mixing_ratio .RCP4.5

From the MPAS manual:
At present, MPAS-A includes parameterizations of physical processes taken from the Weather
Research and Forecasting (WRF) Model 1. Specically, MPAS-A has support for:
Radiation: CAM and RRTMG long-wave and short-wave radiation schemes

What I would like to know is if I can run MPAS and read time-varying GHG concentrations with these schemes like in WRF, for climate change scenario simulations in 2050 for example.
How do I setup MPAS to read the tables? Do I have to compile MPAS with a specific flag like we do for WRF? And if all of this is possible in MPAS, are the table formats the same? Or is there any specific format the table needs to be in?

Apologies for the delay, and thanks very much for the clear description of what you're aiming to do. The short answer is that MPAS-Atmosphere doesn't contain any of WRF's capabilities to read and apply time-varying greenhouse-gas concentrations. I've not really looked at the implementation of this capability in WRF, so I couldn't say how much work it might be to implement it in MPAS-Atmosphere, unfortunately.
Thanks for the reply! I was really hoping I could use MPAS-Atmosphere for this, but I will still use it for other purposes. I appreciate the time and patience with my posts. Have a nice one.