Displaying model configuration and output from the Julia REPL

The specific examples below were generated after running the PALEOcopse COPSE Reloaded example from the Julia REPL, but apply to any PALEOtoolkit model.

Displaying large tables in Julia

Several PALEO commands produce large tables.

There are several options to display these:

  • Julia in VS code provides the julia> vscodedisplay(<some table>) command. As of Jan 2022 this is now usually the best option.
  • Use julia> show(<some table>, allcols=true, allrows=true) to show as text in the REPL.
  • Use julia> CSV.write("some_table.csv", <some table>) to save as a CSV file and open in Excel etc.

Find code and documentation

The documentation for a PALEO reaction can be looked up using the PALEOboxes.doc_reaction command:

julia> PB.doc_reaction("ReactionReservoirScalar")

NB: the VS Code Documentation browser has similar functionality and is often easier to use. The key difference that it looks at definitions visible in the VS code projects and editor windows, whilst doc_reaction looks at definitions available to code in the current REPL ie provided by modules that are currently loaded in the REPL.

Display model configuration

Display parameters:

Examples illustrating the use of PALEOboxes.show_parameters:

To show parameters for every Reaction in the model:

julia> vscodedisplay(PB.show_parameters(model)) # show in VS code table viewer
julia> show(PB.show_parameters(model), allrows=true) # show as text in REPL 
julia> import CSV
julia> CSV.write("parameters.csv", PB.show_parameters(model)) # save as CSV for Excel etc

This illustrates the modularised model structure, with:

  • Domains global, atm, land, ocean, oceansurface, oceanfloor, sedcrust containing forcings and biogeochemical Reactions, with Parameters attached to each Reaction.
  • Additional Domains fluxAtoLand, fluxLandtoSedCrust, fluxOceanBurial, fluxOceanfloor, fluxRtoOcean, fluxSedCrusttoAOcean containing flux coupler Reactions.

To show parameters for a single Reaction:

julia> rct_temp_global = PB.get_reaction(model, "global", "temp_global")
julia> PB.show_parameters(rct_temp_global)    # GEOCARB temperature function parameters

The Julia Type of rct_temp_global PALEOcopse.Global.Temperature.ReactionGlobalTemperatureBerner usually makes it possible to guess the location src/global/Temperature.jl in the source code https://github.com/PALEOtoolkit/PALEOcopse.jl of the PALEOcopse Julia package.

Display Variables:

Show Variables in the model:

Use PALEOboxes.show_variables to list all Variables in the model, or Variables for a specific Domain:

julia> vscodedisplay(PB.show_variables(model)) # VS code only
julia> vscodedisplay(PB.show_variables(model, "land")) # just the "land" Domain

To list full information for all Variables in the model (including Variable linking and current values):

julia> vscodedisplay(PB.show_variables(model; modeldata=modeldata, showlinks=true))

This illustrates the modularized model structure, with:

  • Domains global, atm, land, ocean, oceansurface, oceanfloor, sedcrust containing Variables linked to Reactions (either property-dependencies or target-contributors pairs).
  • Additional Domains fluxAtoLand, fluxLandtoSedCrust, fluxOceanBurial, fluxOceanfloor, fluxRtoOcean, fluxSedCrusttoAOcean containing target-contributor pairs representing inter-module fluxes.

Show linkage for a single Domain or ReactionMethod Variable

To show linkage of a single Variable in Domain "atm" with name "pO2PAL":

julia> PB.show_links(model, "atm.pO2PAL")

To show linkage of a ReactionMethod Variable with localname "pO2PAL", Reaction "ocean_copse" in Domain "ocean":

julia> PB.show_links(PB.get_reaction_variables(model, "ocean", "ocean_copse", "pO2PAL"))

Display model output

Model output is stored in a PALEOmodel.AbstractOutputWriter object, which is available as paleorun.output, ie the output field of the default PALEOmodel.Run instance created by the COPSE_reloaded_reloaded.jl script.

The default PALEOmodel.OutputWriters.OutputMemory stores model output in memory, by Domain:

julia> paleorun.output  # shows Domains

To show metadata for all Variables in the output:

julia> vscodedisplay(PB.show_variables(paleorun.output)) # VS code only
julia> vscodedisplay(PB.show_variables(paleorun.output, "land")) # just the land Domain

Output from a list of Variables or for each Domain can be exported to a Julia DataFrame:

julia> # display data for a list of Variables as a Table
julia> vscodedisplay(PB.get_table(paleorun.output, ["atm.tmodel", "atm.pCO2PAL", "fluxOceanBurial.flux_total_P"]))

julia> # display data for every Variable in the 'atm' Domain as a Table
julia> vscodedisplay(PB.get_table(paleorun.output, "atm"))

julia> # show a subset of output variables from the 'atm' Domain
julia> PB.get_table(paleorun.output, "atm")[!, [:tmodel, :pCO2atm, :pCO2PAL]]

Data from each Variable can be accessed as a PALEOmodel.FieldArray (a Python-xarray like struct with named dimensions and coordinates):

julia> pCO2atm = PALEOmodel.get_array(paleorun.output, "atm.pCO2atm")
julia> pCO2atm.values # raw data Array
julia> pCO2atm.dims_coords # pCO2 is a scalar Variable with one dimension `tmodel` which has one coordinate variable also called `tmodel`
julia> pCO2atm.dims_coords[1] # first dimension, as a Pair dimension => vector of attached coordinates
julia> pCO2atm.dims_coords[1][2][1] # coordinate variable (also a FieldArray)
julia> pCO2atm.dims_coords[1][2][1].values # raw values for model time (`tmodel`) from coordinate variable

Raw data arrays can also be accessed as Julia Vectors using get_data:

julia> pCO2atm_raw = PB.get_data(paleorun.output, "atm.pCO2atm")  # raw data Array
julia> tmodel_raw = PB.get_data(paleorun.output, "atm.tmodel") # raw data Array

(here these are the values and coordinate of the pCO2atm PALEOmodel.FieldArray, ie pCO2atm_raw == pCO2atm.values and tmodel_raw == pCO2atm.dims_coords[1][2][1].values).

Plot model output

The output can be plotted using the Julia Plots.jl package, see Plotting output. Plot recipes are defined for PALEOmodel.FieldArray, so output data can be plotted directly using the plot command:

julia> using Plots

julia> plot(paleorun.output, "atm.pCO2atm")  # plot output variable as a single command
julia> plot(title="Oxygen", paleorun.output, ["atm.pO2PAL", "ocean.ANOX"]) # overlay multiple output variables in one plot

julia> pCO2atm = PALEOmodel.get_array(paleorun.output, "atm.pCO2atm")
julia> plot(pCO2atm) # a PALEOmodel.FieldArray can be plotted

julia> pCO2atm_raw = PB.get_data(paleorun.output, "atm.pCO2atm")  # raw data Array
julia> tmodel_raw = PB.get_data(paleorun.output, "atm.tmodel") # raw data Array
julia> plot!(tmodel_raw, pCO2atm_raw, label="some raw data") # overlay data from standard Julia Vectors

Spatial or wavelength-dependent output

To analyze spatial or eg wavelength-dependent output (eg time series from a 1D column or 3D general circulation model, or quantities that are a function of wavelength or frequency), PALEOmodel.get_array takes an additional selectargs::NamedTuple argument to take 1D or 2D slices from the spatial, spectral and timeseries data. The PALEOmodel.FieldArray returned includes default coordinates to plot column (1D) and heatmap (2D) data, these can be overridden by supplying the optional coords keyword argument.

Examples for a column-based model

Visualisation of spatial and wavelength-dependent output from the PALEOatmosphere.jl ozone photochemistry example (a single 1D atmospheric column):

1D column data

To plot O3 mixing ratio vs height in the 1D atmosphere column, at the last model timestep:

julia> plot(title="O3 mixing ratio", paleorun.output, "atm.O3_mr", (tmodel=1e12, column=1),
            swap_xy=true, xscale=:log10) # plots O3 vs default height coordinate, at the nearest model time to 1e12 yr (ie the last timestep)

To plot results from multiple output times:

julia> plot(title="O3 mixing ratio", paleorun.output, "atm.O3_mr", (tmodel=[0.0, 0.1, 1.0, 10.0, 100.0, 1000.0], column=1),
            swap_xy=true, xscale=:log10, labelattribute=:filter_records) # plots O3 vs default height coordinate

Here the plot recipe expands the Vector-valued tmodel argument to create a composite plot. The optional labelattribute=:filter_records keyword argument is used to generate plot labels from the :filter_records FieldArray attribute, which contains the tmodel values used to select the timeseries records.

This is equivalent to first creating and then plotting a sequence of FieldArray objects:

julia> O3_mr = PALEOmodel.get_array(paleorun.output, "atm.O3_mr", (tmodel=0.0, column=1))
julia> plot(title="O3 mixing ratio", O3_mr, swap_xy=true, xscale=:log10, labelattribute=:filter_records)
julia> O3_mr = PALEOmodel.get_array(paleorun.output, "atm.O3_mr", (tmodel=0.1, column=1))
julia> plot!(O3_mr, swap_xy=true, labelattribute=:filter_records)

The default height coordinate from the model grid can be replaced using the optional coords keyword argument, eg

julia> plot(title="O3 mixing ratio", paleorun.output, "atm.O3_mr", (tmodel=[0.0, 0.1, 1.0, 10.0, 100.0, 1000.0], column=1),
            coords=["cells"=>("atm.pmid", "atm.plower", "atm.pupper")],
            swap_xy=true, xscale=:log10, yflip=true, yscale=:log10, labelattribute=:filter_records) # plots O3 vs pressure

Wavelength-dependent data

julia> plot(title="direct transmittance", paleorun.output, ["atm.direct_trans"], (tmodel=1e12, column=1, cell=[1, 80]),
            ylabel="fraction", labelattribute=:filter_region) # plots vs wavelength

Here tmodel=1e12 selects the nearest model time to 1e12 yr ie the last model time output, and column=1, cell=[1, 80] selects the top and bottom cells within the first (only) 1D column. The labelattribute=:filter_region keyword argument is used to generate plot labels from the :filter_region FieldArray attribute, which contains the column and cell values used to select the spatial region.

Examples for a 3D GCM-based model

Visualisation of spatial output from the 3D MITgcm transport-matrix example (PALEOocean.jl repository)

Horizontal slices across levels

julia> heatmap(paleorun.output, "ocean.O2_conc", (tmodel=1e12, zt_isel=1, expand_cartesian=true), swap_xy=true)

Here zt_isel=1 selects a horizontal level corresponding to model grid cells with index of 'zt' dimension = 1, which is the ocean surface in the MITgcm grid (NB: naming of dimensions is specific to model configurations, as is ordering and sign of depth coordinates hence need for swap_xy option). expand_cartesian=true expands the internal storage from a vector of cells to a 3D cartesian grid.

Vertical section at constant longitude

julia> heatmap(paleorun.output, "ocean.O2_conc", (tmodel=1e12, lon=340.0, expand_cartesian=true), swap_xy=true)

Here lon=340.0 selects a section at the nearest 'lon' coordinate to 340.0 degrees east (NB: naming of dimensions is specific to model configurations, as is ordering and sign of depth coordinates hence need for swap_xy and mult_y_coord options).

Exporting to netcdf to use xarray etc

PALEO output (see below) is in standard netcdf format with the ocean data in the ocean group of a multi-group netcdf file, so can be analyzed using eg the Python xarray package, see example Jupyter notebook in the PALEOocean repository, examples/mitgcm folder.

Save and load output

Model output can be saved and loaded using the PALEOmodel.OutputWriters.save_netcdf and PALEOmodel.OutputWriters.load_netcdf! methods.

Output attempts to follow standard netcdf conventions. NB each PALEO Domain is a separate group in a multi-group netcdf file.

Export output to a CSV file

To write Model output from a single Domain to a CSV file:

julia> import CSV
julia> CSV.write("copse_land.csv", PB.get_table(paleorun.output, "land")) # all Variables from land Domain
julia> CSV.write("copse_atm.csv", PB.get_table(paleorun.output, "atm")[!, [:tmodel, :pCO2atm, :pO2atm]]) # subset of Variables from atm Domain