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  1. M

    When using CAM6 for a 6-month seasonal forecast, there is a problem with accurately simulating the North West Pacific High in July-August.

    Using ERA-5 reanalysis data and ERSSTv5 sea surface temperature data as initial conditions, and running a global model with a 25km grid spacing, it seems that the North Pacific High is not well depicted in the East Asian region during July and August when the modeling starts in March...
  2. S

    hycoef_read: ERROR: file lev does not match model. lev (file, model): 56 32

    Dear sir/madam I have successfully build cam6 with the configuration mentioned below. compset : HIST_CAM60_CLM50%BGC-CROP_CICE%PRES_DOCN%DOM_MOSART_CISM2%NOEVOLVE_SWAV grid : f05_f05_mg17 Model is crashed with the following error: --------------------- Opened existing file...
  3. G

    Output variable of evaporation and precipitation in CAM6

    Hi, I want to plot "precipitation - evaporation" using the simulated CAM6 data. So, I will change user_nl_cam. However, I couldn't find the evaporation variable. Through the "CAM history field ("...
  4. C

    sensitivity experiment about the circulation response to the anomalous soil moisture in the specific region

    Hello all: I was trying to modulate the response of the circulation to the anomalous soil moisture in a specific region in CAM6. I found that there is a variable (atm_in) that may contains the soil data (clim_soilw_file), so, I changed the prescribed soil moisture in it and ran two cases...
  5. J

    CAM6 with SE dynamical core performance decrease from Cheyenne to Derecho

    Hi Derecho / Cheyenne / CESM users, I am planning to run some simulations but realised while setting up and running some test simulations that there is a performance issue that seems to occur using Derecho. A strong decrease in the performance is visible an I/we do not understand why this...
  6. nuvolet

    Run FIST compset in CESM2.2 - error set_time_float_from_date

    Greetings, I am trying to run a case using the FHIST compset. ./create_newcase --case $casename --compset FHIST --res f09_f09_mg17 And specifying the date and step tun such as: ./xmlchange RUN_STARTDATE=20100101,STOP_OPTION=ndays,STOP_N=2,DOUT_S=FALSE The case compiles but gives me this...
  7. P

    Prescribing SERIAL aerosol/solar in CAM6

    Hi, I'm trying to run CESM 2.1.2 - CAM6, in the F1850 compset with prescribed historical aerosol, with and without historical solar variations. I'm trying to use the following options in the CAM namelist: ! evolving volcano prescribed_strataero_cycle_yr = -999999...
  8. nuvolet

    Update emissions inventories for runs beyond 2015

    Greetings, I am trying to make some tests to make runs for years beyond 2015 using CESM2.2 (CAM6.3). I need to get updated emissions inventories because the ones my CESM2.2 is using are from CMIP6 (1849-2015). Anybody knows where could I find and update of this file...
  9. S

    Slab Ocean Mode (SOM) underestimated wind speed

    Dear all, My research involves wind resource evaluation, so I have to simulate the wind speed as close to reality as possible. The compset I use is 2000_CAM60_CLM50%SP_CICE_DOCN%SOM_MOSART_SGLC_SWAV_TEST, a all-active compset for long-term climate simulation. I choose the slab ocean mode to...
  10. nuvolet

    Aerosols radiative properties in the LW

    Greetings, I found the module (~/components/cam/src/physics/cam/aer_rad_props.F90) where aerosol radiative properties are computed in CAM6. In this module from subroutine aer_rad_props_sw returns SW optical props of aerosols, which are mainly extinction optical depth, scattering and asymmetry...
  11. 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.
  12. J

    Suspiciously low CAPE values

    Hi all, I have a run of CAM6-Chem from CESM2.1.3 with coupled land (CLM5-BGC-Crop) and oceans (POP2) forced by SSP1-2.6 GHGs and land use. I wanted to look at some convection parameters, however the output from the model for CIN was 0 everywhere and the output for CAPE was an order of magnitude...
  13. T

    The SO2 + OH -> H2SO4 reaction in CAM6

    Hi forum, It's not clear to me how the reaction rate of SO2 (gas) + OH -> H2SO4 (gas) is calculated in CAM6. The equation report in chem_mech.doc gives this reaction as d(H2SO4)/dt = r3*OH*SO2. When looking through mo_usrrxt.F90 I find this expression for the reaction rate (rxt)...
  14. L

    Prescribe dust and sea salt aerosols in CAM6

    Hi all~ I'm trying to prescribe the dust and sea salt aerosol in two runs with F2010climo compsets, since I hope these two species remain the same when making comparisons. I set the prescribed_aero_nl group in user_nl_cam file as follows: &prescribed_aero_nl prescribed_aero_cycle_yr...
  15. G

    how to add volcanic forcing in CESM2.1.3(CAM6)

    Hello ,everyone: I am planning to conduct volcanic forcing experiments (e.g. 1815Tambora or 1991Pinatubo) with CESM2.1.3-CAM6 to study the influence of a large eruption on climate,. Hoewvwr, I am not sure how to add the needed volcanic forcing file, via ext_frc_specifier or...
  16. H

    How to generate topo file for f05_f05_mg17

    Hello everyone, I am trying to run CESM2.1.3 at the resolution f05_f05_mg17. It seems there is no topo file corresponding to 0.47x0.63 available for CAM6 in I realize that the resampling tool in interpic_new can create my own...
  17. K

    How the CO2 concentration is determined in CMIP6 amip-4xCO2

    Hi all, I want to conduct a set of large ensemble that are similar to CMIP6 amip-4xCO2. However, I don't know how the CO2 concentration is set in amip-4xCO2 as the prescribed CO2 concentration is different every year. The compset I am using is FHIST_BGC, and I guess I am supposed to change the...
  18. H

    How to get the ncdata corresponding to 0.47x0.63

    Hello everyone, I try to get the output including GRAINC_TO_FOOD with 1/2 degree by CESM2.1.3. The surface file and landuse file corresponding to f05_g17 have been generated, and I run this case with compset HIST_DATM%GSWP3v1_CLM50%BGC-CROP_SICE_SOCN_MOSART_SGLC_SWAV and resolution f05_g17...
  19. H

    "lnd_import ERROR: Longwave down sent from the atmosphere model is negative or zero"

    Hello everyone, I use release-cesm2.2.0 and try to get the outputs with 'GRAINC_TO_FOOD'. I run this case with CAM60+CLM%Bgc-Crop+initial file "". Unfortunately, I encountered such error to stop the run. "lnd_import ERROR: Longwave...
  20. K

    Which F compset is identical to the one used in CESM2 AMIP experiment

    Hi, I want to conduct experiments branching off from CESM2 amip experiment same as the CMIP6 amip run. There are a lot of F compsets, like F2000climo, FWHIST, etc. I know CESM1 has a compset named F_AMIP_CAM5, but I didn't find the similar version in CESM2. Thanks! Best, Melody