GlacierPeak 0.2: ERA5 support and animated SVGs
2026-03-22 · Piet van Noorden
GlacierPeak 0.2 adds ERA5 reanalysis data as a first-class source and introduces animated SVG output for retreat timelines.
ERA5 support
The Copernicus Climate Data Store API is notoriously awkward to work with. Requests are asynchronous, the data format is NetCDF4 with non-obvious dimension naming, and the documentation is spread across three different systems. GlacierPeak 0.2 wraps all of this into a single gp.load_era5() call that handles queuing, polling, and conversion transparently.
You need a free CDS API key; once that's configured, querying monthly temperature anomalies for a bounding box is about four lines of Python.
Animated SVG timelines
The retreat timeline renderer now supports animated output. Each year's glacier extent is a separate SVG group; the animation cycles through them at a configurable frame rate using CSS @keyframes. The result is a single self-contained file that plays in any modern browser without JavaScript.
File sizes are reasonable — a 150-year Greenland-wide timeline comes out around 340 kB — because the glacier outlines are simplified with Douglas-Peucker before embedding.