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  1. G

    glc error overshot time

    Hi, I wanted to restart the two experiments of CESM2.1.3 (with compset "F200climo"). So, I changed the env_run.xml as below. ./xmlchange GET_REFCASE=FALSE ./xmlchange RUN_TYPE=branch ./xmlchange RUN_REFDATE=0053-01-01 ./xmlchange RUN_REFCASE=EXP2 -------> case name so, EXP1 or EXP2...
  2. S

    Questions about land-atmosphere interaction

    Dear all, My research focuses on the climate response to land use, so I mainly modify the surface energy balance in the CLM module and view the output files from the CAM module. However, I forgot to reflect the changes in albedo in the variables ALBD and ALBI which will export to CAM. And I...
  3. C

    Plot the wind direction for U10 variable

    Hi,all! I output the 10m wind speed by using U10 variable. Also, I output the TAUX and TAUY(Zonal surface stress) . TAUX and TAUY do not seem to be the U,V variables needed to plot wind direction. UBOT and VBOT seem to be the corresponding variables, but for heights higher than 10 m. Is...
  4. G

    manage_externals/checkout_externals fails(CESM2.1.3)

    When trying to clone release-cesm2.1.3, there is an error due to '/CFMIP/COSPv2.0/tags/v2.1.4cesm/src' path not found and the ./manage_externals/checkout_externals fails So, I modified "repo_url = Tags · CFMIP/COSPv2.0" --> "repo_url =" in...
  5. J

    What are the numbers printed in the atm.log files after nstep, te?

    Hi, With CESM-2.1.3 for example, what exactly do the 4 values printed in the atm.log file at each time step correspond to (physical quantity and unit)? If they are identical for 2 runs for the same time step, does it mean that these 2 simulations are exactly the same, or can it be mere...
  6. J

    Error when testing nudging tools in CESM2.1.3

    Hi, everyone! I try to test the nudging tools in directory 'components/cam/tools/nudging/Gen_Data/'. And I chose ERAI as the target reanalysis product. I edited the csh script according to the instructions in the README file and submitted it for execution. Unfortunately, there was an error. I...
  7. C

    Cam model is stuck at the process "Creating new decomp"

    Dear all, I find the cam model is stuck in the process as "Creating new decomp". I don't know why. I look through cpl.log and find the cam model is stuck. My compeset is F2000climo and res is f09_g09_mg17. The attachment include the slurm file and atm.log.
  8. C

    How to run regional experiments using CESM (coupled CAM and CLM)?

    Hi, I am new to use CESM. I want to use CESM to run high resolution (0.1 degree) regional simulation using the CLM5-BGC-crop coupled with CAM in Europe. But I did not find step-by-step user guide from CESM official website. And I am not sure whether I must use variable resolution CESM. It is...
  9. X

    what is the diffrence between TSKIN from clm and TS from atm

    Hi, everyone, I have finished a simulation using FHIST for periods 1990-1994, i have checked the output of tempeature variable, There is TSKIN in clm and TS in atm, the TS is described as the radiation temperature,but the TSKIN is also the radiation tempeature? I am not sure their differnce, i...
  10. X

    FHIST simulation:"NetCDF: Filter error: undefined filter encountered ERROR: HANDLE_NCERR "

    hi, everyone, when I run FHIST simulation for 1990 (for one year) in supercomputer, and set the following namelist as do_transient_crops = .true. do_transient_pfts = .true. !flanduse_timeseries = '' !fsurdat =...
  11. Jewel

    Remove the radiation effect of a certain aerosol

    Hello everyone I added a new aerosol with dust components in CESM, but I don’t want this new aerosol to have radiation effects. I just want it to be transported and settled along with the dust aerosol. I tried setting the parameters in the '&rad_cnst_nl' corresponding radiation file to 0 or a...
  12. Z

    Solar flux perturbation in RRTMG

    Hello everyone I would like to modify the incident solar flux ('solin') in a selected region and investigate the responses in the atmosphere and ocean. In 'CAMRT' codes, 'solin' is part of a series of computations that can affect other variables. However, in 'RRTMG' codes, 'solin' becomes...
  13. L

    How to interpret RHREFHT?

    Dear CESM/CAM community, I am aiming at using relative relative humidity output from CESM experiments. In doing so, I encountered problems (comprehension issues) with the RHREFHT field: When performing preliminary analyses (using the CESM2 Single Forcing Experiment), the relative humidity...
  14. Y

    Confusion about run CESM with specified dynamics and nudging

    Greetings, If I want to run CESM with specified dynamics or nudging in the atmosphere in the future, and I specify the scenario, such as ssp245. Could I do it this way? Could I first simulate the meteorological conditions of 2030 and then use the simulated data for nudging? Thanks in advance.
  15. C

    how did the lowcloud effect the surface temperature?

    Hi,all! I wanna ask the question:how did the lowcloud effect the surface temperature? Because I find the increase of lowclloud fraction can decrease the Tmin in CESM2.1.3. The result not consisit of my common sense. We usually think the thick and low cloud can keep the surface warm in the...
  16. J

    How to directly get atmosphere variables at specific pressure level?

    Hello, I notice that I can output these variables at specific pressure level directly by set fincl1='U200','V200','U850','V850','OMEGA500','OMEGA850'. But it seems UV at other level (like 700,500hPa) can not be gotten in that way. I konw it can be gotten output the whole level of U or V or...
  17. nuvolet

    How to know if I am running CAM or CAM-Chem

    Greetings, How could I know from a simple CESM run, if I am using CAM or CAM-Chem?. How could I switch/change from to another? Thanks.
  18. E

    How to appropriately calculate radiative forcing imbalance

    When running simulations with volcanic forcing in a fixed sea-surface temperature condition to get an estimate of the forcing, what output variables are the appropriate ones to use? From what I understand, the standard way to do this is to calculate it as the sum of the shortwave + longwave...
  19. B

    How to turn off the transfer of CO2 from ATM to LND

    Dear All, I am running two FHIST_BGC cases to study the impact of LULCC on radiative forcing of GHGs in global, without considering their feedback. This needs GHGs to be sent from the land to the atmosphere, and not from the atmosphere to the land. The default CCSM_BGC = CO2A, it says "adds...
  20. B

    Adding a sphere solid variable to CAM to see its atmosphere transport

    Hello everyone, I am a beginner for CESM, and want to use CAM for a global atmosphere transport of a new sphere solid particle, which is not included in CAM. The transport just refer to simple physical transport process without any chemical reactions. But I have no idear how to add it, and...