diff --git a/doc/ChangeSum b/doc/ChangeSum index b61ceae1e4..7567b779e0 100644 --- a/doc/ChangeSum +++ b/doc/ChangeSum @@ -1,5 +1,6 @@ Tag Who Date Summary ============================================================================================================================ +release-clm5.0.26 sacks 07/29/2019 Add a CN precision control call to fix problems related to small negative values release-clm5.0.25 erik 05/29/2019 Change two files from NetCDF-4 format to NetCDF-3 (because some machines have trouble with NetCDF-4 in pnetcdf) release-clm5.0.24 erik 05/22/2019 Correct ndep end year for SSPs, 2-degree CMIP6WACCMDECK with C-isotopes off, fixes mksurfdata for high resolution release-clm5.0.23 erik 05/15/2019 Update cime to bring in CO2 transient files for the CMIP6 SSP's as well as presaero for three of them diff --git a/doc/release-clm5.0.ChangeLog b/doc/release-clm5.0.ChangeLog index fad475126f..48093e5361 100644 --- a/doc/release-clm5.0.ChangeLog +++ b/doc/release-clm5.0.ChangeLog @@ -1,4 +1,167 @@ =============================================================== +Tag name: release-clm5.0.26 +Originator(s): sacks (Bill Sacks) +Date: Mon Jul 29 18:11:26 MDT 2019 +One-line Summary: Add a CN precision control call to fix problems related to small negative values + +Purpose of this version: +------------------------ + +Small negative values (roughly roundoff-level different from zero) in +frootc (and possibly other quantities) were occasionally creating +problems with carbon isotope fluxes and FPI in the first time step of +the year, at the time of transient landcover change. This tag fixes the +problem by introducing an extra call to SoilBiogeochemPrecisionControl +in between computing the patch-level transient landcover fluxes and +moving these to column-level. In particular, this truncates small +negative values of decomp_cpools_vr_col to zero, which prevents the +previous blow-ups. + +For most of the problematic fields, the explanation seems to be: frootc +can sometimes be negative; this is intentional. Negative frootc causes +negative dwt_frootc_to_litter if the patch in question is shrinking. The +resulting negative fluxes cause problems in the ciso calculation. This +can be worked around by inserting an extra precision control call +between the calculation of the dwt fluxes and the ciso fluxes, so that +small negative dwt fluxes are set to 0. + +This does not necessarily fully explain the issue with FPI, but the +insertion of the extra precision control call fixes that issue, too. + +For more details, see the discussion in +https://github.com/ESCOMP/ctsm/issues/741 + + +CTSM Master Tag This Corresponds To: N/A + +Summary of changes: +------------------- + +Issues fixed (include CTSM Issue #): +- Resolves ESCOMP/ctsm#741 + +Science changes since: release-clm5.0.25 + None + +Software changes since: release-clm5.0.25 + Extra call to SoilBiogeochemPrecisionControl + +Changes to User Interface since: release-clm5.0.25 + None + +Testing: +-------- + + build-namelist tests: + + cheyenne - not run + + unit-tests (components/clm/src): + + cheyenne - not run + hobart --- not run + + tools-tests (components/clm/test/tools): + + cheyenne - not run + hobart --- not run + + PTCLM testing (components/clm/tools/shared/PTCLM/test): + + cheyenne - not run + hobart --- not run + + regular tests (aux_clm): + + cheyenne_intel ---- ok + cheyenne_gnu ------ ok + hobart_nag -------- ok + hobart_pgi -------- ok + hobart_intel ------ ok + + ok means tests pass (other thana expected failures), answers change + as expected for some tests + + regular tests (prealpha): + + cheyenne_intel - not run + cheyenne_gnu --- not run + hobart_nag ----- not run + + regular tests (prebeta): + + cheyenne_intel - not run + cheyenne_gnu --- not run + hobart_nag ----- not run + +Summary of Answer changes: +------------------------- + +If the tag used for baseline comparisons was NOT the previous tag, note that here: previous + +Changes answers relative to baseline: YES + + If a tag changes answers relative to baseline comparison the + following should be filled in (otherwise remove this section): + + Summarize any changes to answers, i.e., + - what code configurations: Transient cases and a few other + configurations as noted below + - what platforms/compilers: all + - nature of change (roundoff; larger than roundoff/same climate; new climate): + Larger than roundoff / same climate + + According to Keith Oleson's analysis of the LMWG diagnostics: + Changes are possibly greater than roundoff-level, but are not + climate changing or scientifically meaningful. + + Other than transient cases (including cases with transient glacier + area as well as those with transient natural vegetation / crop + area), the test suite showed differences in the following cases: + + - Two present-day tests that specify changes in soil layer + structure + (ERI_D_Ld9.ne30_g16.I2000Clm50BgcCruGs.cheyenne_intel.clm-vrtlay + and + ERS_D_Ld3.f10_f10_musgs.I2000Clm50BgcCruGs.cheyenne_intel.clm-deepsoil_bedrock), + have changes in many fields (for the latter: mostly looks + roundoff-level, but a few greater than roundoff-level diffs) + + - The present-day ciso test, + ERP_D_Ld5.f10_f10_musgs.I2000Clm50BgcCruGs.cheyenne_gnu.clm-ciso_flexCN_FUN, + has changes in a few c13 and c14 fields + + - There are changes in many fields in SSP tests + + - ERP_D_P36x2_Ld3.f10_f10_musgs.I2000Clm50BgcCruGs.cheyenne_intel.clm-noFUN_flexCN + (and a similar test on hobart) have roundoff-level changes in + SMINN_vr, SMIN_NH4_vr and SMIN_NO3_vr + + URL for LMWG diagnostics output for new climate: + http://webext.cgd.ucar.edu/I20TR/clm50_cesm20R_2deg_GSWP3V1_issue741_hist/lnd/clm50_cesm20R_2deg_GSWP3V1_issue741_hist.1995_2014-clm50_cesm20R_2deg_GSWP3V1_hist.1995_2014/setsIndex.html + + Will new REFCASES need to be made for cesm and/or CAM?: No + (This will likely be true if the LII tests failed) + +Detailed list of changes: +------------------------ + +Externals being used: No updates + + cism: release-cesm2.0.04 + rtm: release-cesm2.0.02 + mosart: release-cesm2.0.03 + cime: cim5.6.16 + FATES: fates_s1.21.0_a7.0.0_br_rev2 + PTCLM: PTCLM2_180611 + +CTSM Tag versions pulled over from master development branch: None + +Pull Requests that document the changes (include PR ids): None +(https://github.com/ESCOMP/ctsm/pull) + +=============================================================== +=============================================================== Tag name: release-clm5.0.25 Originator(s): erik (Erik Kluzek) Date: Wed May 29 11:16:13 MDT 2019 diff --git a/src/biogeochem/CNVegetationFacade.F90 b/src/biogeochem/CNVegetationFacade.F90 index fed7889819..c3b42209f9 100644 --- a/src/biogeochem/CNVegetationFacade.F90 +++ b/src/biogeochem/CNVegetationFacade.F90 @@ -721,6 +721,13 @@ subroutine DynamicAreaConservation(this, bounds, clump_index, & soilbiogeochem_nitrogenstate_inst) call t_stopf('CNUpdateDynPatch') + ! This call fixes issue #741 by performing precision control on decomp_cpools_vr_col + call t_startf('SoilBiogeochemPrecisionControl') + call SoilBiogeochemPrecisionControl(num_soilc_with_inactive, filter_soilc_with_inactive, & + soilbiogeochem_carbonstate_inst, c13_soilbiogeochem_carbonstate_inst, & + c14_soilbiogeochem_carbonstate_inst,soilbiogeochem_nitrogenstate_inst) + call t_stopf('SoilBiogeochemPrecisionControl') + call t_startf('dyn_cnbal_col') call dyn_cnbal_col(bounds, clump_index, column_state_updater, & soilbiogeochem_carbonstate_inst, c13_soilbiogeochem_carbonstate_inst, &