NCL script to plot climate extreme indices using output from the Climpact script (See Issue #1 )
plot_climpact_automate.ncl.txt

Uses a Shell script to input command line arguments into the NCL script. For example:

• filen='"_climpact.sample_historical_NA_1980-2019.nc"'
• yrStrt='1980'
• yrLast='2019'
• run_name='"coupled_v5"'
• var='"txx"'
• info='"Maximum_value_of_daily_maximum_temperature"'

Reads Observed data (AGCD) for re-gridding to the Observed data set grid.
Lines 21/22 need to be updated to point to Climpact output directory.

As per #11 , this task will be to produce the full suite of Climpact indices in Python for intercomparison.

Script to calculate and output climate extreme indices in NetCDF.

Uses R script from Climpact (https://github.com/ARCCSS-extremes/climpact/). Takes ~8 hours to run on CCAM 1980-2019 25km data when calculating all indices.

Requires the following modules on Gadi:

• module load R/4.1.0
• module load proj/6.2.1
• module load udunits/2.2.26
• module load intel-compiler/2021.3.0
• module load netcdf/4.7.4
• module load intel-mkl/2021.3.0
• module load gcc/11.1.0

Input variables:

• rainfall (kg m-2 d-1 or kg m-2 s-1)
• tasmax
• tasmin
• Each variable must be concatenated into a single file (e.g., ccam_rainfall_19800101-20191231.nc)

I'll start drafting a master document to establish a development roadmap for the CCAM evaluation tools.

I refer to the regridding standards documented as "Observations and GCMs should be regridded to RCM/CCAM grid using conservative area weighted remapping" on https://github.com/AusClimateService/ccam-evaluation/blob/main/evaluation_standards.md.

We agree that conservative method is suitable for upscaling.

For downscaling, it is less clear, whether NN, bilinear or conservative. The use cases are evaluation of mean states, climate indicators, and added-value analyses. I assume using the implementations given by xesmf.Regridder, https://xesmf.readthedocs.io/en/latest/notebooks/Compare_algorithms.html

Do we also want to worry about any height correction (to temperature for instance) using lapse rates? Which can be messy.

I raise this issue for discussion and reaching agreement.

As per discussions with @tha051 today, we're going to run a parallel evaluation of Climpact and Python for computing indices.

The first port of call is to run the Climpact suite against test data (CCAM?) to produces a directory of netcdf files containing the indices. We will then do the same analysis with Python and compare results.

@ngben, as you are already running Climpact are you able to assist with the R side of this evaluation? I will take care of the Python side of things as well as the inter comparison itself.

NCL script to calculate Added Value, bias (CCAM/RCM minus Obs (AGCD) climatology), and RMSE.

Will need to modify script to calculate realised added value (using future simulations).

Works on precip, tasmin, tasmax (other variables can be added but would need to use a different Obs data set)
Calculates average, variance, 1st and 99th percentile AV. CCAM and GDD are regridded to Obs grid.

Uses a Shell script to input command line arguments into the NCL script. For example:

• run_name='"coupled_v6"'
• var='"pr"'
• yyyy_start='1980'
• yyyy_end='2019'
• ls_obs='"/g/data/zv2/agcd/v1/precip/calib/r005/01day/agcd_v1_precip_calib_r005_daily_"'
• ls_rcm='"./data/pr_day_surf.ccam_25.km."'
• ls_gdd='"/g/data/xv83/bxn599/CaRSA/era5_data/tp_day_"'
• obs_var_name='"precip"'
• gdd_var_name='"tp"'
• rcm_var_name='"pr"'

Some variables are outputting data which may need to be processed before running evaluation scripts.

tasmax/tasmin: Fix time units to start from 1/01/1980 and end 31/12/2014 (As an example for NorESM2-MM output). Current output represents the previous 24 hours (e.g., first timestep is 00:00 2/01/1980 and last timestep is 1/01/2015).
rainfall: Output daily data. Current output is hourly.

The above issues can be fixed using CDO to process the data.

Consistent output directory formatting will also make it easier to automate the evaluation scripts.

We need a master list of the minimum set of metrics to be coded up and automated. This issue can be used to discuss and a "metrics.md" file will be written to track progress.