The problem
Glacial lake outburst floods and rock-ice avalanches arrive with minutes of warning, in valleys that cross national borders. The detection has to happen near the source, the decision has to be explainable, and the alert has to reach a downstream community in another country without shipping that country the raw data.
What we built
One board carries all three sensing channels and the radio: an STM32WL55JC with a sub-GHz LoRa radio on the same die, a BGT60TR13C 60 GHz mmWave radar for the surface, a NEO-M8N GNSS receiver for displacement from baseline, an ADXL355 accelerometer for near-field seismics, and an ATECC608A secure element holding the per-node key. A TP4056 charges the Li-ion pack from solar.
The firmware publishes over MQTT with mutual TLS. Telemetry goes at QoS 1, heartbeats at QoS 0, and alerts at QoS 2, because a siren must not be missed and must not fire twice. A single frame carries radar, GNSS, seismic, battery and enclosure temperature, so correlation runs on aligned data rather than three streams stitched together later.
Aether does the rest: ingest, storage, cross-station correlation, source triangulation from arrival times, and routing to civil authorities on both sides of the border with an audit record of who was told and when.
Provenance is enforced, not promised
- Nodes never send a location. They send arrival times and the platform triangulates.
- Three or more stations: the fix is reported as triangulated, with the arrival times shown.
- Fewer than three: the result is labelled a baseline and never dressed up as a fix. An acceptance test enforces this.
- A sensor that has not reported reads as silent, not as zero. Adapters may not fabricate device or telemetry data.
Validation on real events
We ran the detection and geolocation method against two well-documented European collapses using the ETH open network.
| Event | Best station | SNR (2–8 Hz) | Located to |
|---|---|---|---|
| Bondo 2017 · Piz Cengalo | CH.VDL · 32 km | 95 | 6.5 km |
| Blatten 2025 · Birch glacier | CH.SNTZ · 11 km | 3.3 | 10.0 km |
Geolocation uses an ak135 one-dimensional velocity model; the constant-velocity assumption gave 8.4 km on Bondo before we replaced it. Valley-scale accuracy is what routing an alert to the correct downstream community requires.
What we withdrew
An earlier version of our site reported a minutes-ahead seismic precursor at Chamoli. Our own validation audit traced that signal to an M6.0 earthquake in Mindanao 28 minutes before the collapse, and we withdrew it with the earthquake named on the page. A 30-day near-field precursor scan near Bondo found nothing, and we published that too. Precursor sensing remains a research question, not a product; the product is detect-and-route.