Data Sources
Transparency in how we source, process, and present disaster data.
Our Approach
Alertra aggregates data exclusively from authoritative government and scientific agencies. We do not generate or fabricate seismic data. Every earthquake event, magnitude reading, and location coordinate displayed on the platform originates from peer-reviewed, instrument-verified sources.
Our proprietary contributions are the risk scoring algorithm, threat level assessments, and localized analysis — which apply mathematical models to the raw public data to produce actionable insights for each ZIP code.
Primary Data Sources
U.S. Geological Survey (USGS)
earthquake.usgs.gov ↗The USGS Earthquake Hazards Program is our primary data source. We query their public FDSN Web Service API for both real-time and historical earthquake data.
NOAA — National Oceanic and Atmospheric Administration
noaa.gov ↗NOAA provides environmental and atmospheric data used for weather-related hazard monitoring. Data is used under NOAA's public access policies.
National Weather Service (NWS)
weather.gov ↗NWS forecast data and severe weather alerts supplement our disaster monitoring coverage. Data is accessed via the NWS API and is in the public domain.
NASA FIRMS — Fire Information for Resource Management System
firms.modaps.eosdis.nasa.gov ↗NASA FIRMS provides near-real-time active fire data derived from satellite observations (MODIS and VIIRS instruments). Used for wildfire monitoring coverage on the platform.
Our Risk Scoring Methodology
Alertra's threat scores and risk assessments are not sourced from any external agency. They are proprietary calculations developed by Ghost Systems that consider:
- Proximity: Distance from the monitored ZIP code to detected events, weighted by inverse-square scaling.
- Magnitude: Logarithmic energy release as reported by the USGS, with higher weights for M4+ events.
- Recency: Time-decay function that prioritizes recent events over older ones within the 24-hour monitoring window.
- Depth: Shallow earthquakes (≤10 km) receive higher impact scores due to increased surface effects.
- Historical Context: Long-term seismic activity patterns from the USGS catalog are used to establish baseline risk for each region.
These scores are intended as general indicators of seismic activity levels. They should not be interpreted as predictions of future earthquakes or as substitutes for professional seismological analysis.
Data Limitations
Users should be aware of the following limitations:
- Preliminary Data: USGS earthquake reports are initially published with preliminary parameters that may be revised within hours or days as more seismographic data is analyzed.
- Detection Threshold: Very small earthquakes (below M2.0) may not be detected by the USGS network in all regions, particularly in areas with sparse seismometer coverage.
- Latency: There is an inherent delay between an earthquake occurring and it appearing in the USGS data feed, typically ranging from 2 to 20 minutes depending on magnitude and location.
- Coverage Area: Our earthquake monitoring pages display data within a 250-mile radius of each ZIP code. Events outside this radius are not shown on individual location pages.
Questions?
If you have questions about our data sources, methodology, or how we present information, please contact us: