bathy 0.3.0

Lightweight Python package for exploring bathymetry data.

🌐 bathy

bathy, from Greek βαθύς (bathýs), meaning "deep", is a Python package for bathymetric analysis and visualisation.

Documentation · Installation · Features · Examples

Motivation

I found creating bathymetric plots and profiles in Python surprisingly difficult. bathy provides a simple, high-level interface for loading, analysing, and visualising bathymetry data, so you can go from raw grid to reproducible quantitative analysis to finished figure with minimal effort.

Basic usage

Load data

import bathy

# Load from file
data = bathy.load_bathymetry("GEBCO_2025.nc", lon_range=(-10, 0), lat_range=(50, 60))

# Or download from multiple global and regional sources
data = bathy.load_gebco_opendap(lon_range=(-10, 0), lat_range=(50, 60))       # GEBCO ~450 m
data = bathy.load_etopo(lon_range=(-10, 0), lat_range=(50, 60))               # ETOPO 60s/30s/15s
data = bathy.load_emodnet_wcs(lon_range=(-10, 0), lat_range=(50, 60))         # EMODnet ~115 m (Europe)
data = bathy.load_noaa_crm(lon_range=(-72, -70), lat_range=(41, 43))          # NOAA CRM ~90 m (US coasts)

Visualise

bathy.plot_bathy(data)

Analysis overview

bathy.plot_overview(data)

Profiles and canyon analysis

prof = bathy.extract_profile(data, (-11.3, 48.7), (-7.3, 47.2), name="Along-slope")
bathy.plot_profile(prof, show_map=True, bathymetry_data=data)

canyons = bathy.get_canyons(prof, prominence=100)
bathy.plot_canyons(prof, canyons)

Installation

pip install bathy

Or with uv:

uv add bathy

Features

Category	Description
IO	Load from local files (NetCDF, GeoTIFF), GEBCO, ETOPO, EMODnet, or NOAA CRM. Export to GeoTIFF. 28 preset regions included.
Grid operations	Clip, resample (by degrees or metres), reproject, merge overlapping grids, fill NaN gaps
Analysis	Slope, aspect, curvature, rugosity, BPI, geomorphons, contours, smoothing, hypsometric analysis, volume & area calculations
Plotting	Publication-ready bathymetry, hillshade, slope, aspect, overview, 3D surface, depth zones, histograms, interactive maps
Profiles	Extract profiles between points, generate cross-sections, load from file or GeoDataFrame
Profile analysis	Statistics, gradient, concavity, knickpoints, canyon detection, comparison across profiles
Draw	Interactive PyQt6 desktop tool for drawing and editing profiles with drag, undo, and waypoint editing

See the full API reference for details.

Examples

See examples/basic_usage.ipynb, examples/downloading_data.ipynb, examples/profiles.ipynb, examples/grid_operations.ipynb, and examples/draw_profile.py.

Profile drawing

Draw profiles interactively in a PyQt6 desktop window. Requires uv pip install bathy[draw].

uv run bathy-draw path/to/data.nc

• Left-click to add waypoints, right-click to finish a profile, double-click to stop
• Drag waypoints to reposition, press z to undo, shift-click to delete
• Save/load profiles as GeoPackage, toggle visibility per profile

Development

git clone https://github.com/eslrgs/bathy.git
cd bathy
uv sync
pre-commit install

just format  # Format and lint
just test    # Run tests

Use of AI

This project was developed with assistance from AI, which was used for code generation, documentation, and testing.

License

MIT License - see LICENSE for details.