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  1. H

    Create New case using codebase cesm2_1_3_MEGAN turned ON

    Dear Scientists and all, I can create the case without turning on the MEGAN, but when I turn ON the MEGAN (./xmlchange --append CLM_BLDNML_OPTS="-megan"), it results in some error message (ERROR: incompatible settings in drv_flds_in) (attachment). Following are the major settings of my model...
  2. W

    difference between O3_Prod and O3_CHMP

    Hi all, I wonder what the difference between O3_Prod and O3_CHMP. It seems based on output, O3_CHMP is "chemical production rate" in a unit of /cm3/s; for O3_Prod, it is in a unit of molecules/cm3/s. I guess one may be the reaction rate constant, and another one is the reaction rate. But I am...
  3. A

    Experience Modifying CDNC in CAM6?

    Hi all, I'm looking to run CAM6 (as part of a run on CESM2.1) and am looking to change cloud droplet number concentration geographically by latitude / longitude at specified atmospheric pressure levels (below 850 hPa). (I am trying to run a series of experiments to test ocean surface response...
  4. S

    Memory required for CAM-chem

    Hello, If anybody can let me know approximately the space required for a standard CAM-Chem simulation (not fully coupled). I would be using the default meteorology (specified dynamics from MERRA2 with 56 layers) and 1% nudging. The resolution would be 0.5.
  5. O

    chemical boundary and initial conditions for WRF-chem

    Dear all, I am lloking for RCP-based simulations of O3 over Northern Bavaria. Then I need to downscale it by using WRF-chem. According to these papers 1 and 2, I need to the air quality simulations from the modified CESM/CAM-chem . Could you please let me know where I can find these data? Best...
  6. L

    How to add heterogeneous reaction in CAM-chem

    Dear all, I'm running CAM-chem simulation with CESM2.1.0 and I want to add heterogeneous reactions in the FCHIST compset. Where should I change the chemical mechanism? Which file should I add the reactions and individualized reaction rate constant? I really appreciate your helps.
  7. D

    Relationship between the bc_a4 files and num_a4 file.

    So, I've been talking a bit with Simone about this, but I thought I would post it here for others. The bc_a4 file for srf_emis_specifier is the surface emissions of black carbon. This has units of molecules/cm2/s. The num_a4 file is the particle number emissions file for the surface black...
  8. A

    Setting'CAM_CONFIG_OPTS -val '-phys cam5 -chem trop_mozart_mam3'' and got the run error'Cannot specify both bndtvghg and flbc_file'

    Hi everybody, I came up with a problem with CESM1_2_1. I'm running F20C5TR with env_build.xml setting './xmlchange -file env_build.xml -id CAM_CONFIG_OPTS -val '-phys cam5 -chem trop_mozart_mam3''. And I got the run error message '(shr_sys_abort) ERROR: chem_surfvals_readnl: Cannot specify both...