Vn8.4 GA4.0 Release Candidate: RC6.0

From UKCA

This page documents the vn8.4 GA4.0 release candidate xkawa. This job has been run by Luke Abraham on MONSooN.

UKCA code

For this release the relevant and specific UKCA code changes (when compared to the trunk) have been merged into a package branch on PUMA

For the results presented here, revision number 16065 was used.

Initial conditions and forcing

  • xkawa was initialised from the final dump of xjcin (dated 2015-12-01).
  • SSTs and sea-ice use the Reynolds dataset, averaged to produce daily values by meaning over 1995/01/01 to 2005/01/01 using cdo ydaymean.
  • TS2000 (actual date 2000-12-01) conditions were used using the RCP scenario conditions for GHGs and WMO2011 values for ODSs.
  • AR5 emissions are used for the CheST chemistry, including MeOH.

Functionality

Pressure-level output for tracers and chemical diagnostics

All STASH items available in section 34 have an equivalent in section 35. Currently only O3 has been set-up, but other fields can be output by copying this example.

Note: the heavyside function s35i173 also need to put output so that these fields can be processed directly.

RCP Scenario Code

The RCP scenario branch, committed to the trunk at vn8.6, has equivalent functionality available in this job (UKCA lower boundary conditions only - further changes are required to have these affect the GHGs).

To use this functionality a hand-edit is required - see e.g. /home/ukca/hand_edits/VN8.4/UKCA_RCP6.0.ed

Known Issues

Interactive Dry Deposition Scheme

Currently it is possible to request dry-deposition for a species in the ukca_chem_strattrop.F90 module (the first 1 in the last three columns of numbers) e.g.

!  29
chch_t( 29,'N2O       ',  1,'TR        ','          ',  0,  0,  0),  & 
!  30 DD:12,WD:12,
chch_t( 30,'HCl       ',  1,'TR        ','          ',  1,  1,  0),  & 

but if values have not been set in ukca_aerod.F90 and ukca_surfddr.F90 then no dry deposition will in fact be calculated. Please see UKCA Chemistry and Aerosol Tutorial 7 for details as to how to add new values.

If you have this, you should see warning messages such as this in the .leave file:

? Warning Message:  Surface resistance values not set for HCl
? Warning Message:  Surface resistance values not set for HOCl
? Warning Message:  Surface resistance values not set for HBr
? Warning Message:  Surface resistance values not set for HOBr
? Warning Message:  Surface resistance values not set for DMSO
? Warning Message:  Surface resistance values not set for Monoterp
? Warning Message:  Surface resistance values not set for Sec_Org

Currently none of the above species (HCl, HOCl, HBr, HOBr, DMSO, Monoterp, or Sec_Org) are in fact dry deposited in this job configuration.

Low Stratospheric NOy

This can be seen in the profiles of HNO3 below. It is currently attempting to be addressed. For more information, see details from the NOy PEG.

Results

Lightning NOx

The average annual Lightning NOx emitted is 4.03285 Tg(N)/year.

Evaluation Suite Output

Mean over 10 years

Results from individual years

The results of each of the 10-years can be found in the following documents. These were generated from the UKCA Evaluation Suite available on the MONSooN post-processor.