APIs Used & Offered

What Intensity Lab depends on, and what it offers in turn.

Services We Consume

Intensity Lab is built on top of several external services rather than reimplementing them:

USGS ComCat & ShakeMap

The earthquake catalog feed (magnitude, location, focal mechanism) and the ShakeMap grid/station products that drive every intensity calculation on the site. See USGS Earthquake Data & ShakeMap.

SCEC UCVM (Vs30)

Site-specific shear-wave velocity, the primary input for site amplification in every GMPE and BBP calculation. Reached through a dedicated Vs30 service (currently a local UCVM container in production; a metered external routing path exists and is deployed but not yet the live path). See Vs30: Site-Specific Soil Conditions.

SCEC Broadband Platform (via bbpapi)

Physics-based simulated seismograms, accessed as a separately hosted, metered REST API rather than run in-process. See Physics-Based Simulation (BBP).

YouTube Data API v3

Every completed animation (simulated, observed, and ground motion decay) is automatically uploaded as an unlisted video to the Intensity Lab YouTube channel and grouped into a per-event playlist. See Physics Animation (Blender).

Services We Offer

One endpoint here is worth calling from outside this site: a ground motion estimate at coordinates nobody has pre-computed.

POST /api/v1/ground-motion/ — an MMI estimate at any lat/lon within the supported region, for any published earthquake. It needs a free account (JWT bearer token or API key). Site-specific V_s30 is looked up for you; the caller never supplies it.

ask14, bssa14, cy14, cb14 — the four NGA-West2 GMPEs (see ShakeMap vs. GMPE Comparison). Each computes PGA from the earthquake parameters and the site's V_s30, then converts to MMI through the Worden et al. (2012) GMICE. This is the part that is not available from USGS directly.
shakemap_interpolated (default) — bilinear interpolation of the USGS ShakeMap grid. No V_s30, no GMPE: it reports USGS's own estimate of observed shaking at your coordinates.

The response carries the MMI value, the method used, vs30_used (GMPE methods only), from_cache (true when the point was already computed for a gazetteer site), and in_shakemap_coverage (whether it fell inside the ShakeMap grid).

Everything else is this website's own backend

The rest of /api/v1/ — the earthquake list and event detail, per-site intensities, animation listings, and the gazetteer and seismic station lists — is what these pages are rendered from. It is public and unkeyed and you are welcome to read it, but it is published because the site runs on it, not as a product.

Create a free account to get started, or read the full API reference →