Hi Dave, Chris et al.
First, thank you for the many links/input/recommendations. There is now a viable plan to try and get this to work.
Below is a list of the JRA55-do variables used in ACCESS-OM2 (properties are taken from here), and what I think their corresponding variables in the ESM1.5 UM are. All the UM output below is saved 3-hourly, and the time and time_0 variables are the staggered 3h time coordinate.
| JRA55-do variable | UM atm variable | UM Dimension | UM Description |
|---|---|---|---|
| tas 10m air temperature (θA), units: K | fld_s03i236 | (time, lat, lon) | TEMPERATURE AT 1.5M units : K |
| huss 10m specific humidity (qA), units: Kg kg−1 | fld_s03i237 | (time, lat, lon) | SPECIFIC HUMIDITY AT 1.5M |
| uas 10m eastward wind, units: m −s 1 | fld_s03i209 | (time, lat, lon_u) | 10 METRE WIND U-COMP |
| vas 10m northward wind, units: m −s 1 | fld_s03i210 | ( time, lat_v, lon) | 10 METRE WIND V-COMP |
| psl Sea level pressure (SLP), units: Pa | fld_s00i409 | (time, lat, lon) | PRESSURE AFTER TIMESTEP units :Pa |
| rsds Downward shortwave (QDSW), units: Wm−2 | fld_s01i201 | (time_0, lat, lon) | NET DOWN SURFACE SW FLUX: SW TS ONLY units :W m-2 |
| rlds Downward longwave (QDLW) , units: Wm−2 | fld_s02i201 | (time_0, lat, lon) | NET DOWN SURFACE LW RAD FLUX units :W m-2 |
| prra Rainfall flux, units: kg m ^{-2} s ^{-1}, | fld_s05i214 | (time_0, lat, lon) | RAINFALL RATE: LS+CONV KG/M2/S |
| prsn Snowfall flux , units: kg m ^{-2} s ^{-1} | fld_s05i215 | (time_0, lat, lon) | TOTAL SNOWFALL RATE: LS+CONV KG/M2/S |
| friver Total river runoff , units: kg m ^{-2} s ^{-1}, | missing friver from ESM? | ||
| licalvf Solid water runoff from Antarctica represented as calving flux from Depoorter et al. (2013), units: kg m ^{-2} s ^{-1} | missing from ESM? |
Here I have outlined the approximate next steps and the links to the scripts/resources I will likely use. Warning, all this is hypothetical and the list will grow, but I will keep this thread updated.
- convert temp and humidity to 10m height, to follow JRA55-do.
* Script to possibly do that linked from @aekiss here: Support ERA5 forcing · Issue #242 · COSIMA/access-om2 · GitHub -
Remap/regrid the ESM1.5 UM data so that it works with MOM5. (@dkhutch from my reading, you wrote the converse but I think this is what you meant?)
*https://github.com/COSIMA/access-om2/blob/master/tools/make_remap_weights.py: need to modify script to have atm option as UM, um_grid file does exist in esm_grids.
* done by Dave H - what to do for missing friver/licalvf values – just use JRA55-do RYF input?
- Initial conditions: I would like to use the historical ESM1.5 ocean/ice restart files from
/g/data/vk83/configurations/inputs/access-esm1p5/modern/historical/restart/and feed that into ACCESS-OM2.The file names match up, but in OM2 each nc file is split. (‘ocean_neutral.res.nc.0000’, ‘ocean_neutral.res.nc.0001’ etc in OM2 for example, vs. ‘ocean_neutral.res.nc’) Would this naming situation would affect me using the ESM ocean/ice restarts?unaffected, but can collate as suggested two replies down.- Need to interpolate the ocean restart files, as the ESM1.5 and OM2 have different ocean vertical resolution
One final thing: For science reasons, it has been thrown out there for my project that using ACCESS-OM3 would be useful. The pros are isopycnal coordinates and that changing the forcing could be easier with NUOPC (my vague understanding from what Chris said above?). The cons are that OM3 is still in development, and that there is some documentation now (here in this thread!) on how this could be done in OM2. I will be at ANU Thu-Fri this week, so will try to catch a few people in person but any opinions on this here are very welcome. @ShayneM
Cheers everyone,
Ellie
P.S. I am also aware of a running list of potential problems that can occur when changing the forcing for ACCESS-OM2 as outlined here. I don’t think they currently apply but will keep in mind.