About geohazardwatch

geohazardwatch is an open-source add-on for the ngdpbase platform that brings volcano and earthquake data into pages via simple markup tags.

It is not a live data feed — it works by importing snapshots from public scientific APIs and making that data available to plugins. This keeps the site fast and resilient to upstream outages, at the cost of some data freshness.

What data is available

Dataset	Provider	Coverage
---------	----------	----------
Volcano catalog	Smithsonian Global Volcanism Program (GVP)	~2,600 Holocene and Pleistocene volcanoes worldwide
Eruption history	Smithsonian GVP	Historical eruption records, confirmed and uncertain
Earthquake data	USGS Earthquake Hazards Program	Global M4.5+ events, past 7 days (default)
US volcano alerts	USGS Hazard Alert Notification System (HANS)	65 monitored US volcanoes

Data sources

Smithsonian Global Volcanism Program (GVP)

The GVP maintains the world's most comprehensive catalog of volcanic activity. The geohazardwatch volcano catalog is drawn from the GVP WFS API and covers:

Basic facts: name, GVP number, country, region, coordinates, elevation
Classification: volcano type, dominant rock type, tectonic setting
Epoch: Holocene (erupted in the last ~11,700 years) or Pleistocene (older)
Eruption history: confirmed and uncertain eruptions with VEI, start/end dates, and evidence type

Source: volcano.si.edu Data citation: Global Volcanism Program, 2025. Volcanoes of the World (v. 5.3.4). Smithsonian Institution. https://doi.org/10.5479/si.GVP.VOTW5-2023.5.3

USGS Earthquake Hazards Program

The USGS monitors global seismic activity in near-real-time. geohazardwatch imports the M4.5+ past-7-days feed by default. Earthquakes are cross-referenced with the GVP volcano catalog to identify events within 50 km of a known volcano.

Each earthquake record includes:

Magnitude and depth
Location and coordinates
PAGER economic alert level (green / yellow / orange / red) where assessed
Tsunami flag (USGS-issued, not a guarantee of actual wave generation)
Nearest volcano within 50 km (if any)

Source: earthquake.usgs.gov Feed: USGS GeoJSON Feeds

USGS Hazard Alert Notification System (HANS)

HANS provides real-time alert levels for the 65 US volcanoes monitored by the USGS Volcano Hazards Program. Alert levels follow a four-level scale (NORMAL → ADVISORY → WATCH → WARNING) paired with aviation colour codes (GREEN → YELLOW → ORANGE → RED).

Coverage is limited to US volcanoes only — primarily in Alaska, Hawaii, the Cascades, and the western US. For global volcanic activity use the GVP-sourced plugins.

Source: volcanoes.usgs.gov Live HANS data: volcanoes.usgs.gov/hans-public/api/

Data freshness

All data on this site is a point-in-time snapshot, not a live feed. Data is imported by running the addon's import scripts manually (or on a schedule if configured).

Dataset	Recommended refresh cadence
---------	---------------------------
Volcano catalog	Weekly (changes rarely)
Eruption history	Weekly
Earthquake data	Every 15–30 minutes for current activity
US volcano alerts	Every 5–15 minutes for current hazards

If you need live data, visit the source portals directly (links above).

Plugin reference

Seven markup plugins are available:

Plugin	What it renders
--------	----------------
`[{VolcanoInfobox number='...'}]`	Sidebar card for a single volcano
`[{VolcanoList}]`	Paginated, filterable table of volcanoes
`[{VolcanoSearch}]`	Interactive live-search widget with dropdowns
`[{VolcanoMap}]`	Interactive Leaflet map with volcano markers
`[{EarthquakeList}]`	Paginated table of recent earthquakes with alert badges
`[{EarthquakeMap}]`	Interactive Leaflet map of earthquake events
`[{HansAlerts}]`	US volcano alert level table

Full usage guide with examples: Plugin Guide

Open source

geohazardwatch is open source and available at github.com/jwilleke/geohazardwatch. The ngdpbase platform that powers this site is at github.com/jwilleke/ngdpbase.