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Major bugs and issues clm5

Keith Oleson edited this page Sep 13, 2019 · 27 revisions

The following summarizes major bugs and issues found since the release of CLM5

BUGS THAT HAVE NOT BEEN COMPLETELY FIXED ON MASTER NOR ON THE RELEASE BRANCH

  • Issue#803: Assumption that building width (Wb) equals street width can be relaxed and Wb can be derived from morphology

    There is an implicit assumption in the urban building energy model that building width equals street width. However, this assumption can/should be relaxed and building width can be derived from the morphology dataset. A simulation with the new equations indicate that as expected, for froof=0.5, answers are identical (because H/Ws = H/Wb). Differences in other cases depend on the degree of departure from froof=0.5 and the presence and magnitude of space heating and air conditioning. A full assessment of differences by variable, season, density type, and region can be found in the attached file in Issue#803.

    This bug has not yet been fixed.

    ALL CMIP6 simulations are affected.

  • Issue#675: Enabling carbon isotopes changes answers for transient cases

    13C and 14C soil C, litter C, root C, and soil respiration (below-ground quantities) are incorrect in simulations with land cover change. Above-ground quantities are ok.

    During land cover transition, 14C and 13C root carbon that should be transferred into 14C and 13C litter pools is mistakenly transferred to the bulk C litter pool. This has effectively no impact on bulk C or anything downstream in the coupled system. It affects 13C and 14C soil C, litter C, root C, and soil respiration where there has been land cover change. Note that all runs without land cover change are unaffected.

    The following variables published on ESG have been removed for all transient simulations (currently this is: amip, deforest-globe, historical, land-hist, land-hist-altStartYear, land-hist-cruNcep, land-hist-princeton, ssp126, ssp126-ssp370Lu, ssp370, ssp370-ssp126Lu, ssp585):

    c13Land, c13Litter, c13Soil, netAtmosLandC13Flux, rac13, rhc13, c14Land, c14Litter, c14Soil, netAtmosLandC14Flux, rac14, rhc14

    The following above-ground variables are ok and have not been removed from ESG:

    c13Veg, c14Veg, gppc13, and gppc14

    This bug has been fixed on master (ctsm1.0.dev036) and on the release branch (release-clm5.0.22), however, all current initial files generated from historical runs have incorrect C13/C14 pools/fluxes and so any simulation initialized from these files, even with the bug fix, will be incorrect.

    The following CMIP6 simulations are affected: CMIP6 Simulations

  • Issue#592: Use of C13/C14 timeseries for non-transient control cases gives incorrect input when run long enough

    1850 or 2000 compsets non-transient simulations with CLM4.5/CLM5.0 and isotopes on will be using constant 1850 conditions until you run for more than 1850 years, when it will start running through the transient atm C13/C14 time-series instead of using constant 1850 conditions.

    No current spinups are affected.

    This bug has not yet been fixed.

    NO CMIP6 simulations are affected.

BUGS THAT HAVE BEEN COMPLETELY FIXED ON THE RELEASE BRANCH BUT NOT ON MASTER

  • Issue#624: QNOEVAP history output is incorrect.

    QNOEVAP output from publicly available simulations has been removed.

    This bug has been fixed on the release branch (release-clm5.0.20) but not on master.

    The following CMIP6 simulations are affected: CMIP6 Simulations

  • PR#611: Reseed generic crops and increase totvegc threshold from 0 to 1

    A user reported odd (blocky) spatial patterns appear in generic crop leafc for BGC simulation when initialized from BGC-Crop (see Issue#608). To fix this, we now allow for reseeding of generic crops and increase the totvegc threshold that triggers this from 0 to 1 gC/m2. This is a work-around solution that addresses the isssue of dead generic crops in an accelerated-mode BGC simulation initialized from our current BGC-Crop initial files.

    This bug has been fixed on the release branch (release-clm5.0.20) but not on master.

    NO CMIP6 simulations are affected.

  • Issue#590: Sporadic large CO2 uptake causing coupled CLM_CO2_TYPE=prognostic run to abort

    This is due to the fact that a large negative flux is coming from xsmrpool_to_atm_patch, which occurs at harvest in a single time step. This was fixed by dribbling the flux at crop harvest to the atmosphere over about a half year.

    This bug has been fixed on the release branch (release-clm5.0.16) but not on master.

    NO CMIP6 simulations are affected.

  • Issue#545: Antarctica ice shelves are being treated as wetlands rather than glaciers

    This can impact science in scenario runs where the snowpack melts.

    This bug has been fixed on the release branch (release-clm5.0.16) but not on master.

    The following CMIP6 simulations are affected: CMIP6 Simulations

BUGS THAT HAVE BEEN COMPLETELY FIXED ON MASTER BUT NOT ON THE RELEASE BRANCH

  • Issue#780: Possible bugs in CNFireLi2016Mod.F90

    A conversion of latitude from degrees to radians is not being done in the computation of "ig" (total ignitions). Diagnostics of the effects are available on the gitub issue page. Another possible bug was verified to be correct as is.

    This bug has been fixed on master (ctsm1.0.dev063) but not on the release branch.

    ALL CMIP6 simulations are affected.

  • Issue#785: Threshold for explicit snow pack initiation should use frac_sno_eff, not frac_sno

    This affects (a) runs with use_subgrid_fluxes = .false. (NOT the default); (b) urban points in all runs. The impact should be fairly small in both cases, since this just changes the timing of when an explicit snow pack is initiated, rather than using an unresolved (0-layer) snow pack. However, no formal simulations have been done to assess the impact on climate.

    This bug has been fixed on master (ctsm1.0.dev057) but not on the release branch.

    ALL CMIP6 simulations are affected (by (b) only as above).

  • Issue#783: frac_sno is always 0 for lake points

    No formal simulations have been done to assess the impact on climate.

    This bug has been fixed on master (ctsm1.0.dev057) but not on the release branch.

    ALL CMIP6 simulations are affected.

  • Issue#704: FUN code logic to reduce or increase carbon allocation used for uptake is reversed

    Carbon allocation to uptake responds to CN(uptake-cost) and CN(actual). The intended implementation is: For C:N less than the target C:N, C allocation is reduced with cost. For C:N greater than the target C:N, C allocation is increased with high C:N. However, the actual implementation is reversed.

    Our assessment is that the impact is relatively small, but would affect climate; however it doesn’t appear to strongly affect transient C response.

    This bug has been fixed on master (ctsm1.0.dev043) but not on the release branch.

    ALL CMIP6 simulations are affected.

BUGS THAT HAVE BEEN COMPLETELY FIXED ON MASTER AND THE RELEASE BRANCH

  • Issue#538: In transient pft simulations with use_crop=.false., %crop does not advance from 1850 values

    Configurations affected: All transient pft configurations with create_crop_landunit = .true. and use_crop = .false. (which requires do_transient_crops = .false.)

    This bug has been fixed on master (ctsm1.0.dev013) and on the release branch (release-clm5.0.11).

    NO CMIP6 simulations are affected.

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