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Quick start: all-dummy run

This tutorial runs PROTEUS with all modules set to "dummy" backends. No external solvers (AGNI, SPIDER, SOCRATES) are needed; the run completes in under a minute and exercises the full coupling architecture. Use this to verify your installation and understand the code flow before moving to production runs.

Prerequisites

  • PROTEUS installed (pip install -e ".[develop]")
  • FWL_DATA environment variable set

No external solvers, spectral files, or EOS data are required.

The configuration file

PROTEUS ships with an all-dummy config at input/dummy.toml. The key settings are:

  • Planet: 1 M\(_\oplus\), starting fully molten (T\(_\mathrm{magma}\) = 4000 K, \(\Phi\) = 1). Volatile budget of 10,000 ppmw H, 1000 ppmw C, 500 ppmw N, 500 ppmw S.
  • Star: fixed solar luminosity (no evolution)
  • Orbit: 0.5 AU, weak tidal heating
  • Interior structure: Noack & Lasbleis (2020)1 analytical scaling laws
  • Interior energetics: heat-capacity integrator with prescribed solidus (1700 K) and liquidus (2700 K)
  • Outgassing: melt-fraction-dependent partitioning; 10% of volatiles are always in the atmosphere (finite solubility floor), with the atmospheric fraction increasing as the mantle solidifies
  • Atmosphere: grey-body opacity (\(\gamma\) = 0.5)
  • Escape: disabled (rate = 0), so the run reaches solidification
  • Chemistry: parameterised vertical profiles (offline)

The simulation terminates when the global melt fraction drops below the solidification threshold.

Running the simulation

conda activate proteus
proteus start --offline -c input/dummy.toml

The --offline flag skips data downloads. The run should complete in under 30 seconds.

Expected output

The run creates a directory inside output/ named with a timestamp. Check plots/plot_global_lin.png for a multi-panel overview. Your output should look similar to this:

Dummy tutorial output
All-dummy tutorial output. (a) Heat fluxes: the interior and atmospheric fluxes track each other as the planet cools; absorbed stellar flux (ASF) is constant. (b) Surface partial pressures: H2O dominates (~104 bar), with CO2, N2, and SO2 as minor species; pressures increase as solidification forces dissolved volatiles into the atmosphere. (c) Surface temperature: monotonic cooling from 4000 K to ~1700 K (solidus). (d) Atmospheric mole fractions: H2O at ~95%, stable throughout. (e) Mantle evolution: melt fraction drops from 1 (fully molten) to ~0 (solidified) over ~23,000 yr; the rheological front (orange) tracks the melt fraction. (f) Volatile partitioning: dissolved fraction decreases from ~90% to ~0% as the melt fraction drops, transferring volatiles from the interior to the atmosphere.

To regenerate these plots from your own output:

proteus plot -c input/dummy.toml all

Understanding the helpfile

Open runtime_helpfile.csv in the output directory to see the full time series. Key columns:

Column Units What to expect
Time yr Stays at 0 for the first 3 iterations (init stage), then advances to ~23,000 yr
T_magma K Decreases monotonically from 4000 to ~1700
Phi_global 1 Drops from 1.0 to ~0.01, triggering the solidification stop
P_surf bar Increases from ~7,000 to ~70,000 as volatiles outgas
F_atm W m\(^{-2}\) Outgoing longwave radiation; decreases as the surface cools
F_int W m\(^{-2}\) Interior heat flux; tracks F_atm in the dummy coupling
M_planet kg Constant throughout (mass conservation)

What to look for

  1. Cooling and solidification: T_magma decreases smoothly from 4000 K. When it crosses the solidus (~1700 K), Phi_global approaches zero and the run terminates with "Planet solidified!!".

  2. Outgassing: as the melt fraction drops, volatiles transfer from the interior to the atmosphere. P_surf increases and the dissolved fraction in panel (f) decreases. This is the core coupling feedback that the production modules (CALLIOPE, Aragog) compute with full thermodynamics.

  3. Energy balance: the OLR (red line in panel a) and interior flux (orange dashed) track each other because the dummy atmosphere directly couples F_int = F_atm. The absorbed stellar flux (blue dashed) is constant because the star is fixed.

  4. Mass conservation: M_planet should remain constant within rounding. No atmospheric escape occurs in this configuration.

Next steps

  • Vary the greenhouse effect: increase atmos_clim.dummy.gamma toward 1.0 to slow cooling (more opaque atmosphere traps more heat) or decrease it toward 0 for faster cooling (more transparent)
  • Enable escape: set escape.dummy.rate = 1e4 and params.stop.escape.enabled = true to see atmospheric mass loss
  • Change volatile inventory: increase H_budget to 50,000 ppmw for a thicker steam atmosphere, or decrease it to 1,000 ppmw for faster solidification
  • Move to production modules: the Earth analogue tutorial uses Aragog, Zalmoxis, CALLIOPE, and AGNI for a quantitatively meaningful simulation

See also: Model description | Dummy modules | Coupling loop | Configuration reference | Output format

  1. Noack, L. & Lasbleis, M., Parameterisations of interior properties of rocky planets, Astronomy & Astrophysics, 638, A129, 2020. SciX. ↩