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  1. W

    How to extract land/sea mask from region_mask.ieeei4?

    Hi all, I am trying to run a LGM simulation with CESM1.2.2 and B1850 compset. I have a set of ocean restart files (gx1v6) and corresponding mask files to take advantage of. Unfortunately the bnd_topo file for CAM on hand has land/sea mask slightly different from the ocean files due to different...
  2. L

    How to open and modify forcing files in .ieeer8 file format?

    I barely know this file format, except that it is probably a binary file, and I have no idea how to deal with it. Can Python/MATLAB/NCL... open it? What should I do if I want to modify the values in this files? Is it possible to transform .ieeer8 to .nc? Any messages about it is appreciated...
  3. B

    A random error occurred while replacing the POP2 component runtime in CESM version 1.3

    I tried to replace the system's own POP2 component with another ocean component on cesm1_3_beta17_sehires38, and created a case where compset was GIAF and res was f19_g16_rx1, but the following random errors occurred when the run process was repeatedly executed. May I ask why? Using the same...
  4. N

    CESM 2.1.3 - POP failing when looking for input header file for ts_WOA13v2_jan_ic_gx1v7_20170706.ieeer8

    To Whom this may concern, I have ported CESM2 to the Niagara supercomputer on SciNet (part of Digital Research Alliance of Canada). The config* files are attached, compiler used is intel with mpilib of intelmpi. I have also attached the log files. This includes the atm, cesm, cpl, lnd, ocn, and...
  5. A

    Does SSH_2 include the inverse barometer contribution to sea level?

    Hi all, I am using the CESM2 Large Ensemble dataset and wanted to understand the "sea surface height" variable, SSH_2. The dataset is in /glade/campaign/cgd/cesm/CESM2-LE/ocn/proc/tseries/day_1/SSH_2/. Is SSH_2 supposed to be the "dynamic sea level," referred to as "zos" according to CMIP6...
  6. R

    ERROR: ocn_run_mct:: Internal pop2 clock not in sync with Sync Clock. POP BGC

    Hello, everyone! Thanks for opening this thread. I am running fully coupled climate simulation (use B1850, ) with CESM1.2. The ocean tracer module is set to "iage ecosys" for this simulation. The model has been running successfully for 3000 years.When I change to 'hybrid' continue to run the...
  7. R

    ERROR: ocn_run_mct:: Internal pop2 clock not in sync with Sync Clock POP module

    Hello, everyone! Thanks for opening this thread. I am running fully coupled climate simulation (use B1850) with CESM1.2. The model has been running successfully for 3000 years.When I change to 'hybrid' continue to run the next (I also change the dtime by modifying ATM_NCPL in env_run.xml file...
  8. M

    Very quick question about Paleotoolkit: gridkmt_nc2bin.f90

    Hi NCAR paleo friends, Recently I am using the NCAR paleotoolkit to create a binary KMT file from a .nc one. I used this code: However, when I look at Line 37, this...
  9. Z

    ocean -only MODE use forcing data,and "bulk_NCEP"

    I want to run ocean-only mode, use compset C, with my own forcing data. After created new case. I am tying to force the ocean model with external surface heat flux (SHF) and surface fresh water flux (SFWF). The forcing_shf_nml consist of SST, air temperature, air humidity, downward shortwave...
  10. Q

    POP aborting——FATAL ERROR: SAVG_0D_AREA is zero

    When I ran the case of the simulation of 165Ma with cesm-dt2.0, this error came and I haven't seen this before. So I want to know what the error is and how to solve it. Thx a lot :) and the below is my set in pop2
  11. S

    Accumulating TEND_TEMP only at shallowest model level

    I have modified the POP2 source code before to write out variables only at select depths before and am trying the same for TEND_TEMP at the shallowest model level. My plan is to just create a new 2d variable. Here are the steps I have taken (steps 1 and 2 are from within passive_tracers.F90) 1...
  12. J

    Previously successful run crashes after 18 years

    Hi all, I'm running a coupled atmosphere-ocean compset in CESM2.2.0 on Cheyenne. I have successfully run this compset for 10 years - in the next run of 10 years it crashed at year 18. The error in the cesm.log is: WHL, oc_tavg_helper is already associated; reset the tavg fields 0: sysmem...
  13. W

    UVel USUBM and UISOP

    Hello everyone I am a new user of CESM/pop, and one doubt came to me when analyzing the ocean velocities output. Might be simple to answer, but I couldn't find the answer anywhere. I noticed U/V is separated into three components,e.g., for V = VVEL,VSUBM,VISOP. My question is: does VVEL already...
  14. C

    Preindustrial equilibrium temperature in CESM2.2 vs CESM2.1

    Hi, I'm running a fully coupled simulation at 2 degree resolution (compset: 1850_CAM60_CLM50%BGC_CICE_POP2%ECO%ABIO-DIC_MOSART_CISM2%NOEVOLVE_WW3_BGC%BDRD, resolution: f19_g17), as a hybrid run branching from year 401 of the 2 degree PI control (b.e21.B1850.f19_g17.CMIP6-piControl-2deg.001)...
  15. W

    Too weak AMOC in G_INTERANNUAL compset using f45_g37 grid

    Hi, I am running CESM 1.2.1 using the G_INTERANNUAL compset. Forcings are from the CORE II data set (1949-2009, 62 years per cycle). When I use the f09_g16 grid, the AMOC seems fine. But when I repeat the above simulations using the f45g37 grid, AMOC seems to be pretty weak. I guess the...
  16. M

    Lack of JRA55 data on cheyenne

    I found that there is no SWUP and DN10 data under this direction: /glade/p/cesmdata/cseg/inputdata/ocn/jra55/v1.3_noleap. I'm wondering If I want to use POP2 for OGCM simulation experiments with JRA55 data for forcing, would it affect the results if I use SWUP and DN10 data under the original...
  17. L

    branch run error: (ocn_import): qsw aggregation mismatch exceeds threshold

    Hello, I intend to run G compset(only pop) for 100 years first, then turn on MARBL component from 101th year for the subsequent simulation, in order to shorten spin-up time. So I try to do a branch run at 101th year. First I run G compset(no MARBL) for 100 years to get restart files(CASE1)...
  18. U

    FATAL ERROR: Empty stream

    Hello, everyone. I cp $CCSMROOT/models/ocn/pop2/input_templates/gx1v7_tavg_contents to $CASE/SourceMods/src.pop/ and comment out unnecessary streams (only retain stream 1, which is h.). And I modified the tavg_nml in pop_in the $CASE/run/ to delete unnecessary output stream. Then I run...
  19. D

    Understanding this strange looking MOC output

    Hi, Shown below are two MOC diagnostics which directly plot the Atlantic MOC streamfunction generated by POP2. The one on the left is a PI MOC while the one on the right is for a LGM-like simulation in which the Bering Strait and the Canadian Archipelago are closed and small coastline changes...
  20. T

    Running ocean-only with changing CO2 values

    I want to run a G1850ECO_IAF case with changing CO2 values overtime. For this I changed OCN_CO2_TYPE = diagnostic, CCSM_BGC = CO2A and DATM_CO2_TSERIES = 20tr. It runs for at least 1 month but the output of ATM_CO2 is constantly 0. Did I miss an option or is CCSM_BGC set to the wrong value?