Minutes of the chemistry working group meeting 29/1/2014

From UKCA

Gas-Phase Chemistry Telecon

29/01/14

Agenda 1) Updating reaction rates (AA)

2) Evaluation of model output (NB found bug in OH Lawrence script) (AA)

3) Strategy for understanding UTLS O3 bias in troposphere (AA)

4) Model stability (FO’C)

5) Water vapour bug (FO’C)

6) Drift in model performance (FO’C)

7) Upper boundary condition (FO’C)

8) UMvn9.1 Code Freeze (FO’C)

9) Any other business

10) Details of next telecom


Present – NLA, PTG, ATA, MD, FO’C, GAF Minutes: Item (0) ATA – Should we put documents on the twiki or on the UKCA wiki NLA – Transparency means that UKCA wiki would be best ATA – ACTION put minutes and documents on to the UKCA wiki ALL – ACTION to think of suitable name.

Item (1) ATA – Should we lodge the mechanism data? FO’C – Its possible to lodge anciliary data to FCM FO’C – There is scope to improve the way that the meta data is incorporated FO’C – Review process is not simple. MD – There is a guideline for the role of a strategic reviewer. FO’C – The plots would be a useful tool for helping the reviewers. Give a first order impression of whether there going to be any changes. ATA – should the tools, which are needed, to evaluate the chemistry be under FCM. FO’C/NLA – Pros and cons of how to store the mechanism data and or tools FO’C – No need to rush this and do a bad job. ACTION All to think about how best to make progress.

Item (2) MD – Don’t want to overload the evaluation plots! No need to duplicate diagnostics FO’C – Can add the data from ACCENT. ACTION to get the data FO’C – Also need to produce a very succinct level of evaluation that ESM people can “connect” with. ACTION All to think about extended and reduced model output.

Removed discussion of item 3 from agenda. Item (4) FO’C – NR solver appears to be unstable with tropisop AND glomap mode are on. CheST + glomap seems stable. Plan of action needed to (1) understand the causes (2) fix it! NLA – Is this just a mode related issue? Can we try running without MODE? FO’C – Run tropisop with aerosol chemistry set to 0 and systematically test the impact of adding DMS, Terpenes etc. NLA – Have there been runs with offline oxidants. NLA – What level is the code dying? MD – High up (level 57). GAF – Do we need to revaluate the sanity checks in the solver. ATA – MJP has given ASAD code to increase the number of s/s species. FO’C – CJ is looking in to this. NLA – Is this related to the upper boundary conditions? GAF – Are there issues with how the relaxation to the UBC is performed. Add a sponge layer? FO’C – ACTION will try and isolate the causes of the instability. ATA – ACTION will look at the rates.

Item (5) FO’C – When water vapour is pulled in to the atmosphere from D1 it was not being converted properly in tropisop. GAF – This would cause the chemical atmosphere to be too dry. Obviously this would have big impacts on OH. ATA – ACTION look for this bug in 7.3 jobs. FO’C – ACTION to look into the jobs again.

Item (6 - 9) FO’C – RC3 for tropisop (stability aside) is drifting badly. A couple of fixes need to be made – CH4 boundary condition, upper boundary condition GAF – There is a bug in the LNOx scheme NLA – Declan Finney has sent this to us and we need to check. Our LNOx distribution looks OK so not sure we are effected by this. ATA – The Ox production looks odd in this model version – too much production at high southern latitudes – is this a LNOx issue? FO’C – ACTION to pick up where the model runs were left. Will turn of the GLOMAP MODE and aerosol chemistry bits. In particular the UBC for NOy looks very high. FO’C – To send over jobs for UCam to look at on MONSooN. ATA – ACTION to assess the impact of different UBC (following Zadies work). Talk to GAF about implementing the sponge. FO’C – 9.0 released end of Feb. Climate configuration available mid March. Mid may deadline for code submission. 9.0 running under Rose – not an ideal set up. Items slated for inclusion – BVOC emissions (GAF) top priority; Bug fix branch (FO’C) – add the water vapour bug fix, coriolis parameter. All agree that the timeline prevents getting changes to tropisop in in time. FO’C – Timeline for ENDGAME still in flux. ACTION to keep us posted. FO’C – Leeds to advertise the JWCRP post. Interviews will be mid March. ATA involvement depends on number of other interviewers.

Item (10) ATA – ACTION Schedule next meeting for mid March. GAF – Skype next time