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  1. S

    [Question] Modifications of SW and LW flux at certain layers

    Dear CESM community, My colleague and I are trying to perform some simulations using CESM1.2.2 that modify SW and LW at different layers. For example, we want to modify the model to reflect more SW upward or reduce the outgoing longwave at the atmospheric layer near the tropopause. I checked...
  2. nuvolet

    Build a new case after modifying module code in CAM6-CESM2.2

    Greetings, I am modifying a module in the CAM6.0 (nudging.F90) and in during the process to build a case I get this message and the case is not completely built. Somebody knows why this directory is not created? Thanks in advance
  3. L

    How Parallel Offline Radiative Transfer Model (PORT) continue with restart file

    Dear all, I'm using PORT and drive it with offline data for many years. For example, running over input data for years 0001-0010. What I have tried is set the "offline_driver_fileslist" and I have successfully finish year 0001. Then at year 0002, I set and replace the offline_driver_fileslist...
  4. nuvolet

    Creating data streams - CESM2.2

    Hi everyone, I was wondering if the process to create new data streams in CESM2.2 is similar to previous version. I found this old documentation (, and I would like to know if I could use it for new cases in the...
  5. S

    Add/create a passive tracer in CAM

    Dear all, I am trying to learn how to add a passive tracer in the CAM module but am still confused after some previous posts: (e.g., CAM tracer
  6. J

    Understanding proper usage of create_clone for cases that are designed to resubmit from restart files

    I have a case that I have set to resubmit 5 times, writing a restart file at the end of each run: ./xmlchange STOP_OPTION=ndays ./xmlchange STOP_N = 720 ./xmlchange REST_OPTION=ndays ./xmlchange REST_N=720 ./xmlchange RESUBMIT=5 I'm not absolutely sure that this usage is correct, but it does...
  7. nuvolet

    Meteorological data sets

    Hi all, I am reading the documentation for CAM6.0, and in chapter 7about input datasets, in section 7.5 for meteorological data sets it is claimed that CAM uses GEOS5 and MERRA2 meteorological reanalysis. How could I know which datasets are used?. Both?. How could I customize that input? Is...
  8. J

    SourceMods with redundant filenames

    Say I want to build the model with a modification to CAM in the file src/physics/simple/physpkg.F90 How do I ensure that the model knows to modify this file rather than src/physics/cam/physpkg.F90? Should I insert this into SourceMods in the CIME case directory by replicating the directory...
  9. X

    How to diagnose the CH4 radiative forcing?

    Hi! I am a green hand of CESM , and recently I have been learning how to diagnose the radiative forcing. The guidance includes radiative forcing diagnosis for aerosols, such as modified the user_nl_cam to dignosed the Black carbon radiative forcing:(9. Physics modifications via the namelist —...
  10. J

    How to properly turn on AOA tracers?

    I am trying to perform a simple Held-Suarez configuration in CAM, with AOA tracers active. I first spun up the model with a period of 1.5 years without including -age_of_air_trcs to CAM_CONFIG_OPTS I am then trying to do a longer run using this spun up state as the initial condition. For this...
  11. L

    Influence of CO2 in CESM

    Hello, I want to find out more about how CO2 influences for example on the global temperature, and how this is reflected in the model (theoretically). Therefore, I'm trying to find the underlying equations in the CESM1 or 2 model which depend on values/parameters related to CO2. I've searched in...
  12. Q

    where to get the available history variable for certain compset

    hello! i was testing a dry dynamical core run and add some output variables in user_nl_cam files. however, it turned out that some variables are not available in this idealized run. i just wonder generally where can we get a list of available variables for certain compset? i found a master field...
  13. X

    The questions about namelist.

    Hi. I just started to get in touch with CESM, I made the modification according to the guidance on calculating aerosol radiative forcing in CAM6.3, but it failed, I suspect I made a mistake when I modified namelist, my method is to copy the code that needs to be modified directly into the last...
  14. X

    ERROR: Could not find all inputdata on any server(Cannot download file since it lives outside of the input_data_root)

    HI. I tried to copy the method in "9.5 Example-Black Carbon Radiative Forcing" in the CAM6.3 Use's guide to Diagnostic BC radiative forcing, I copied the following line to the end of user_nl_cam and then run the program: mode_defs = 'mam4_mode1:accum:=', 'A:num_a1:N:num_c1:num_mr:+'...
  15. W

    Difference between TS (surface temperature, radiative, CAM) and TG (ground temperature, CLM)?

    Hi everyone, I'd like to inquire about the difference between surface temperature (radiative) and ground temperature? The first one is TS from CAM while the second is TG from CLM. More specifically, I am currently using CESM1.2.2 with CAM4 and CAM5. Somebody seems to have asked this before...
  16. H

    emission file for SSP370 are missing?

    Hi, I didn't find the following files for SSP370 in the input data file ( Could you please let me know where can I find those files? missing data: C2H4_bb CB1_bb, CB2_bb OC1_bb OC2_bb I just found these...
  17. J

    Output BVOC species mixing ratios in CAM6

    Hi all, I'm a CESM2 novice interested in BVOC emissions. I'm planning some runs using a CESM2 build that couples CLM5 and CAM6. I know that the MEGAN model in CLM5 produces various BVOC species and that CAM6 can be set to show the MEGAN fluxes from the land to the atmosphere by adding the...
  18. S

    Looking for CAM history fields like clean sky downwelling solar flux at surface and TOA.

    Hello scientists, I am looking for cam history fields like clean sky downwelling solar flux at surface and TOA. The word "Clean" refers to all-sky flux without the aerosols effect or simply No aerosol sky solar flux. All-sky flux @ surface refers to Downwelling solar flux at surface (FSDS). Is...
  19. J

    Understanding a vague error message

    I'm trying to run from initial conditions on file, pointed to by NCDATA. I'd like to verify that I've constructed the initial conditions properly by running a 30-day sim with FV3 (--res C24_C24_mg17) and --compset FADIAB. However, the run crashes immediately with a vague error message in the...
  20. J

    turn off aerosols for indirect radiation effects

    Hi all,I want to know how to turn off the indirect radiation effects of aerosols.