raising co2, ch4 levels in waccm/carma?

[eric_wolf@colorado_edu]

I am running waccm/carma using cam3_1_9_brnch_waccm on a Mac Pro. I am trying to raise the CO2 and CH4 mixing ratios to be ~1000 ppm each for use in paleoclimate studies.

The usual pathways to setting CO2 and CH4 levels do not seem to be working properly. The namelist variables co2vmr and ch4vmr have no effect on the respective mixing ratios whatsoever. I have also tried changing the CO2 and CH4 fields in master initial conditions file (namelist variable 'ncdata') with little success. When changing the ic file, in most cases the model crashes while in others it will run but the mixing ratios are set to incorrect levels and tend to evolve back to the baseline case over time ([co2]=~350 ppm, [ch4] ~ 1.7 ppm). In both scenarios I have turned off upper boundary conditions on CO2 and CH$ mixing ratios.

At the moment I am at a bit of a loss about what avenue to pursue next. Any suggestions would be greatly appreciated.

Thanks,
Eric

 

[eric_wolf@colorado_edu]

As an addition to my above question.

Is there a way turn off mozart chemistry so that the constituent mixing ratios read in by the initial conditions file remain fixed and do not evolve over time?

 

[marsh]

The easiest way to turn off mozart chemistry is to configure with the -chem waccm_ghg option instead of waccm_mozart. I believe that under this option the namelist variables co2vmr and ch4vmr are operational.

Dan