Earth Plotter

earthplotter.org

A free map of the world's land and sea in your browser, from open data. It draws the OpenStreetMap base map with relief and contours, depth shading and isobaths, satellite imagery (and, in some countries, their national aerial photos: the layer's ⋯ names them), seamarks, shipping density, ocean data from Copernicus Marine and NASA's daily imagery. Measure and draw on it, export the view as GIS data, and save areas to use without a connection.

Not for navigation. Positions, coastlines and depths come from open datasets of varying accuracy. Depths are elevation models (GEBCO's, and EMODnet's in European seas), not soundings.

What you can do

Choose layers by task; each says where its data comes from, under what licence, and how fine it is. Click the sea for its depth. Search a place or type coordinates. Set one time for every layer that changes with time, and one depth for the ocean variables. See what is normal for a month: wave height, temperature, salinity and currents averaged over decades, and the severe waves of European seas. Measure distances, bearings and areas along the real curve of the Earth, in kilometres or nautical miles. Save the view in the browser to open it without a connection: the base map, relief and contours, depths and isobaths, and seamarks. Draw points, shapes of real size, lines, areas and labels; keep them in groups; attach lines to what they touch; place copies along a line and connect them to roots. Read a line's elevation profile, at sea and on land. Export the view as a picture, as GIS data that QGIS opens, or your drawing as GeoJSON. Install the page as an app on a phone.

Everything runs in your browser, with no server of its own: the page fetches each layer from its provider as you look at it. Every layer works without an account or a key, but one optional choice: Esri's sharper satellite imagery, which needs your own free ArcGIS key (docs/esri-key.md).

Privacy

Drawings, saved areas and your location stay in your browser; tile requests tell each provider which area you are looking at, and place names you type go to the search provider. An Esri key, if you add one, stays in your browser and goes only to Esri. The About dialog in the page says in full what leaves your browser and what stays in it; each layer's ⋯ names its provider.

Hosting a copy

The page is static: the site/ folder can be served by any web server, with no build and nothing to install. What a copy inherits, what it must provide itself, and how to set it up: docs/development.md.

More

• docs/architecture.md: how the code is shaped, and why.
• docs/depths.md: where the depths and isobaths come from, and how far to trust them.
• docs/drawing-ui.md and docs/drawing-format.md: the drawing tools and their file.
• docs/takeaways.md: what was learned the hard way.
• ROADMAP.md: what is open, what to research, what is not planned.

Licence

The code is under GPL-3.0-or-later; see LICENSE. The libraries in site/vendor/ keep their own licences, copied beside them. Map data and imagery stay under their providers' licences.