AEOLIS Idealised Coastal Dune Blowout Simulation Workflow

AEOLIS SIMULATION OF BLOWOUTS STARTING FROM IDEALISED ALONGSHORE-UNIFORM DUNES :

* Overview:

This repository provides a simple workflow to run idealised coastal dune
simulations using the AEOLIS model. It reproduces the modelling approach
described in:

Castelle, B., de Vries, S., Burvingt, O., Nicolae Lerma, A., Hesp, P.
Process-based modelling of coastal dune blowout initiation, development
and stabilisation (Journal of Geophysical Research – Earth Surface,
submitted)

The workflow automatically: • Generates an idealised dune morphology •
Generates vegetation cover • Builds an AEOLIS input file from a template
• Runs AEOLIS • Stores the output

* Folder structure

Aeolis_Version/ → AEOLIS model installation Example_Run/ → Folder where
simulations are executed

Example_Run contains: - run_single_aeolis.py Main script to prepare and
run simulations - aeolis_template.txt AEOLIS configuration template -
wind.txt Wind forcing time series - tide.txt Tide time series - ne.grd
Non‑erodible layer - callback.py Vegetation callback used by AEOLIS

* How the workflow works

1)  Topography generation The script creates an idealised Gaussian dune.
    Optional features: • Offshore slope • Blowout notch • Random
    topographic noise

Generated files: z.grd → bed elevation x.grd → x coordinates y.grd → y
coordinates

2)  Vegetation generation Vegetation density is created from: •
    Elevation threshold • Initial vegetation density • Optional random
    noise Vegetation is removed inside the blowout notch.

Example output: vge_ZVeg0.5_DVeg0.15.grd

3)  Automatic AEOLIS input file The script reads aeolis_template.txt and
    replaces the vegetation file name. Example output:
    aeolis_ZVeg0.5_DVeg0.15.txt

4)  Running AEOLIS The script launches: aeolis run

AEOLIS produces aeolis.nc which is renamed automatically.

* Running a simulation

1)  Make sure AEOLIS is installed and available: aeolis –help

2)  Move to the example folder: cd Example_Run

3)  Run the reference simulation: python3 run_single_aeolis.py –Zveg 0.5
    –Dveg 0.15 –hv 0.4 –Hd 2.5 –hp 0.0 –Ln 0.0 –Hn 0.0 –zl 1.0 –Xs 150.0
    –Ss 0.1

* Main parameters

Vegetation Zveg → elevation threshold for vegetation Dveg → initial
vegetation density hv → vegetation noise amplitude

Morphology Hd → dune height Wd → dune width hp → topographic noise

Blowout notch Ln → notch size Hn → notch depth

Shoreface Xs → start of nearshore slope Ss → nearshore slope

Changing forcing conditions

Wind forcing: Edit wind.txt to test different wind climates.

Tides: Edit tide.txt.

Vegetation behaviour: Modify aeolis_template.txt. Important parameters
include: V_ver, lateral, germinate, gamma_vegshear, hveg_max.

Debug mode (no AEOLIS run)

python3 run_single_aeolis.py –Zveg 0.5 –Dveg 0.15 –no-run

* Output files

z.grd, x.grd, y.grd → grid and bed vge_.grd → vegetation aeolis_.txt →
AEOLIS input aeolis_*.nc → simulation output

NetCDF output contains: zb, rhoveg, uws, uwn, ustars, ustarn, Cu, qs, qn

* Typical workflow

• Change CLI parameters → morphology experiments • Edit wind.txt → wind
climate experiments • Edit aeolis_template.txt → vegetation experiments

This setup provides a straightforward and reproducible way to explore
interactions between wind, vegetation and dune morphology.