Aus400

Revision as of 01:32, 15 April 2020 by S.wales (talk | contribs) (Model Modifications)

HighResLAM is a project to run a regional ACCESS model at 400m resolution over the whole of Australia, as part of NCI's STRESS2020 test of Gadi

NCI Project Description
ly62 STRESS2020 CLEX

Scripts and patches used for the model run are available at https://github.com/coecms/highreslam

HighResLam clouds.png.png

Experiment Details

There are two LAM levels being actively run, at 2.2km and 400m resolution. External boundary conditions come from BARRA, the BoM regional reanalysis

The two nest levels are run as individual Rose suites

  • Mid level domain: u-bm651
  • Inner domain: u-bn283

The period of interest for this experiment is the period around the landfall of TC Debbie, from 20170327T0000Z to 20170329T000Z. The 2.2 km domain has 24 hours of spinup, the 400m domain has 6 hours of spinup.

400m Domain

The domain is 13194 x 10554 grid points, of size 0.0036 degrees square, centred at 27.8S 133.26E

The domain boundaries work out to [109.510800, 157.005600] longitude in degrees_east, [-46.797200, -8.806400] latitude in degrees_north

Outputs

Temporary processed outputs for testing purpose are available at /g/data/w35/saw562/HighResLAM/output

Visualisations

Inputs

Input data and raw outputs are available at /g/data/ua8/HighResLAM

Model Modifications

  • Due to the large domain size it was not possible to generate ancillary files for the full 400 m domain with standard tooling. Instead the files were generated in four quadrants, then the quadrants were combined into single files covering the full domain using Mule
  • Due to memory and walltime limitations the spiral search used in the UM reconfiguration to give data to newly resolved coastal grid points was performed offline, by saving the input values to a file, running the existing algorithm on that file using a larger number of CPUs, then re-running the reconfiguration reading from the processed files instead of performing the spiral search online.
  • There were some errors in the reconfiguration when gathering a full field from the individual MPI ranks, which resulted in artefacts at the MPI domain boundaries for some fields
  • Model orography was generated from SRTM data processed using ANTS' ancil_orographic_wavedrag.py, rather than the default IDL based script from the Nesting Suite. Orography over PNG was smoothed with an additional 3km Raymond filter before interpolation to the model grid. The orography field was inserted directly into the initial conditions file rather than using the reconfiguration to avoid the boundary errors described above.