View source for High Res MIP


=Global Atmosphere 7.1 N216= 

To compare the performance on our systems with the MetOffice results, we have created a local version of the MetOffice's GA7.1 N216 model, specifically of their High Resolution Model Intercomparison Project. The ID of this rose is <span style="font-family:monospace">u-an493}}, which is a copy of the MetOffice's {{u-ai718</span>, with only very few changes to make it compatible with NCI raijin:

* The paths to the ancillary files were adjusted
* The number of CPUs was changed to 26x32 (with 2OMP threads)
* The submission scripts were adapted for NCI (PBS, modules, etc)

==Performance== 

* There are two recommended decompositions:
** By default, the job runs on 24 nodes (16 cores each), specifically 24x16, with no OpenMP. This is a reasonable compromise between speed (~28 hr/yr) and cost (~11kSU/yr)
** The fastest decomposition is 26x32, with 2 OMP threads, or 104 nodes. Adding more CPUs only increases overhead. It can model a year in about 11 hours, but at a cost of 20kSU per model year.
* The resubmission frequency is set to 1 month, and should not be changed to less than 10 days to not impact performance.

==Obtaining the Job== 

As the rose is located on the MetOffice Collaboration Repository, you need an account there [link missing].

<syntaxhighlight lang=bash>
$ mosrs-auth
$ access-auth
$ rosie copy u-an493
</syntaxhighlight>

==Notes== 

* The metadata for the UM is located in <span style="font-family:monospace">/g/data/access/AMEL/GA7.1-HRMIP/rose-meta/um-atmos/HEAD}}, which is under version control at {{https://metoffice-mirror/svn/um/main/branches/dev/scottwales/r31906_easyaerosol_raijin/rose-meta/um-atmos/HEAD</span>
* In the '''Machine Options''' section there is a definition of a variable <span style="font-family:monospace">HRMIP_DIR}} which is a path prefix to keep the actual filenames for the MetOffice as little changed as possible. Currently it points to a location under {{/g/data1/w35/saw562/</span>, but this might have to change in the future.

==External Links== 

http://collab.metoffice.gov.uk/twiki/bin/view/Project/HiResCL/HiResCLPRIMSimulations
https://code.metoffice.gov.uk/trac/ukcmip6/wiki/CMIP6HighResMIP
https://code.metoffice.gov.uk/trac/ukcmip6/wiki/CMIP6HighResMIP/highresSST-present/HadGEM3-GC31-N216-ORCA025
https://code.metoffice.gov.uk/trac/ukcmip6/wiki/CMIP6HighResMIPForcings
https://code.metoffice.gov.uk/trac/roses-u/log/a/n/4/9/3/trunk

=Global Atmosphere 7.1 N96= 

A version of HighResMIP is also available at N96 resolution, using the job '''u-as709'''.

As in the n216 version, only minor changes were made to the model's data paths (Local copies of the files used at the Met Office can be found under <span style="font-family:monospace">/g/data1/w35/saw562/HighResMip/data</span>)

On Raijin's 'normal' queue with 16x16 processors this costs ~ 600 SU per model year, and takes ~ 6 hours per model year to run.

=Transpose AMIP style N216 runs= 

Transpose AMIP style hindcast runs can be run using the job u-ap508. This allows researchers to set the model start date to an arbitrary time and focus on specific weather and climate events.

This configuration is based on the HighResMIP configuration, but uses a Gregorian calendar rather than the original 360 day calendar.

==Initialised fields== 

The following fields are sourced from the ERA Interim GRIB datasets under <span style="font-family:monospace">/g/data1/ub4</span>. Details of how this works can be found in [https://code.metoffice.gov.uk/doc/um/vn10.8/papers/umdp_303.pdf | UMDP 303]

{| 
|''' '''ECMWF short name''' ||''' '''Description''' 
|-
| z || Geopotential height 
|-
| lsm || Land sea mask 
|-
| sp || Surface pressure 
|-
| skt || Skin temperature 
|-
| sd || Snow depth 
|-
| stl1 || Soil temperature by layer 
|-
| stl2 
|-
| stl3 
|-
| stl4 
|-
| u || U wind 
|-
| v || V wind 
|-
| t || Temperature 
|-
| q || Specific humidity 
|-
|}

Additionally a number of model fields required by the model are initialised to zero, and require some spin-up time

{| 
|''' '''STASH code''' ||''' '''Description''' 
|-
| 0155 || Accumulated surface runoff 
|-
| 0156 || Accumulated sub-surface runoff 
|-
| 0157 || Gridbox area 
|-
| 0290 || Daily accumulated lake flux 
|-
| 0511 || Inland basin flow 
|-
|}

==Updated Fields== 

Sea surface temperature and sea ice are updated from ERA-Interim at 6 hourly intervals. The ancillary files use for this are generated by the `<span style="font-family:monospace">install_ancil}}` task, they are regridded to the model resolution using NCO then converted to UM format with {{mkancil</span>.

The `<span style="font-family:monospace">install_ancil</span>` task also sets up the calendar for EasyAerosol input files. As these files are large (the total size is ~1TB) the script first extracts just the dates important to the run before changing the calendar.

==External Links== 
[https://code.metoffice.gov.uk/doc/um/vn10.8/papers/umdp_303.pdf | UMDP 303: Reading GRIB data using the UM]
[http://www.cawcr.gov.au/researchletters/CAWCR_Research_Letters_9.pdf | Roff et al. 2012 - Initializing ACCESS from Era-interim data]

[[include component="page" wikiName="climate-cms" page="Index UM" editable="1"]]

[[Category:Unified Model]][[Category:Atmosphere Models]]