Foster Falls Hillshade from Digital Elevation Model

Rockfall Hazard Analysis Platform

Talus aims to mitigate one of the top causes of death / injury in outdoor rock climbing (rockfall) by providing climbers with concrete rockfall risk scores for their local wall. This is done via an end-to-end pipeline from raw DEM ingestion to route risk visualization. Freeze-thaw risk windows combined with GPU-identified source zones above a route create actionable information for mitigating rockfall hazards.

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Tech Stack

Layer	Technology
Microservices	Go (5 services)
GPU kernels	CUDA
Database	PostgreSQL + PostGIS
Containerization	Docker, Docker Compose
Frontend	Leaflet.js, vanilla JS
CI	GitHub Actions
DEM source	USGS 3DEP 1/3 arc-second (~10m/cell)
Weather	Open-Meteo API

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GPU Benchmark

Kernels run on a GTX 1060 3GB against the Foster Falls, TN. CPU baseline is single-threaded sequential execution of the same computation.

Kernel	GPU	CPU	Speedup	Cells
Sobel slope/aspect	569ms	6,041ms	10.6×	116.9M
Plan/profile curvature	565ms	1,180ms	2.1×	116.9M
Terrain Ruggedness Index	318ms	1,633ms	5.1×	116.9M

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What It Does

1. Ingests a USGS 3DEP GeoTIFF DEM and USGS NGMDB geology polygons for a climbing area
2. Runs GPU-accelerated terrain analysis to identify rockfall source
3. Fetches NOAA HRRR temperature forecasts and computes freeze-thaw risk windows
4. Scores route risk using a proximity-based formula
5. Fires webhook alerts when risk exceeds a configured threshold
6. Displays results on a Leaflet.js map dashboard with source zone overlay, route overlay, freeze-thaw timeline, and GPU benchmark table

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Architecture

Four Go microservices communicating via REST, one standalone CUDA terrain binary invoked as a subprocess, and a shared PostgreSQL + PostGIS database.

USGS 3DEP ──► S1 Ingestion (Go) ──► S2 Terrain Preprocessing (Go)
                                              │
                                       CUDA Binary (C/CUDA)
                                       Sobel · Curvature · TRI
                                              │
NOAA NOMADS ──► S4 Hazard Analysis (Go) ◄────┘
                        │
                        ▼
               S5 API Gateway (Go) ──► Browser / Mobile Client
                        │
               PostgreSQL + PostGIS

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Services

Service	Language	Responsibility
S1 — Ingestion	Go	GeoTIFF parse, GPX ingest, geology ingest
S2 — Terrain	Go + CUDA subprocess	GPU terrain derivatives, source zone detection
S4 — Hazard	Go	Proximity risk scoring, freeze-thaw compute, webhook alerts
S5 — Gateway	Go + Leaflet.js	REST API, static dashboard
PostgreSQL + PostGIS	SQL	Shared persistent store, spatial queries

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Prerequisites

• Docker and Docker Compose
• Go 1.25+
• CUDA 12.2 toolkit

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Setup

git clone https://github.com/ethan-howes/talus
cd talus
cp .env.example .env
# fill in POSTGRES_PASSWORD and CUDA_TERRAIN_BINARY_PATH
docker compose -f deployments/docker-compose.yml --env-file .env up --build

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Data Sources

Dataset	Source	Use
3DEP DEM (1/3 arc-second)	USGS National Map	Primary terrain input
National Geologic Map	USGS NGMDB	Rock type and simulation parameters
HRRR Forecasts	NOAA NOMADS	Freeze-thaw temperature forecasts
GPX Routes	Personal / AllTrails	Route geometries for risk intersection

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