Data Sources & Provenance
Calchis is built on authoritative, publicly verifiable data sources. Every feed, every historical dataset, and every model parameter is traceable to its origin. This page documents what powers the platform, how often it updates, and why you can trust it.
Live Data Sources
Feeds polled by automated workers on a fixed cadence. Each source is independently monitored for uptime and freshness.
USGS Earthquake Hazards Program
every 5 minEarthquake events, magnitude, depth, location; ShakeMap intensity contours for significant events
Gold standard for seismological data. Global feed, US-filtered for display. Source of all earthquake consequence rings.
License · Public domain (US Government work)
NOAA National Hurricane Center
every 30 minHurricane advisories, track forecasts, wind radii, wind-speed probabilities
Official US tropical cyclone authority. Advisories issued every 6 hours during active storms, supplemented by intermediate advisories.
License · Public domain (US Government work)
NWS Damage Assessment Toolkit
every 30 minObserved tornado and wind damage: NWS survey tracks, damage points and EF-rated polygons
Drawn by NWS survey teams on the ground, usually within one to two days of the event. Preliminary by the service's own statement; official figures follow in NCEI Storm Data.
License · Public domain (US Government work)
USGS Short-Term Network (high-water marks)
every 30 minObserved flood and surge high-water marks: position, surveyed elevation and datum, mark type and survey quality class
Flagged and surveyed by USGS field crews in the days and weeks after the water falls; each mark carries its stated survey uncertainty (Excellent ±0.05 ft to VP >0.40 ft). A point, not an extent.
License · Public domain (US Government work)
NASA FIRMS VIIRS
every 15 minActive fire hotspots, thermal anomalies
Satellite-based fire detection from VIIRS instrument on Suomi NPP. US-filtered. Complements NIFC official perimeters with early detection.
License · NASA Earth science data — free and open; acknowledgement requestedWe acknowledge the use of data from NASA FIRMS (Fire Information for Resource Management System), part of NASA's Earth Science Data and Information System.
NIFC Active Fire Perimeters
every 12 hOfficial wildfire perimeters, acreage, containment
Authoritative wildfire boundary data from the National Interagency Fire Center. Used for official consequence ring geometry.
License · Public domain (US interagency)
NWS Flood Alerts
every 10 minFlood, flash flood and coastal flood warnings and flood watches, with alert polygons where NWS issues them
The National Weather Service's own alert API. Gauge stage, flood stage and forecast crest are parsed from the alert text when the warning quotes them; Calchis holds no gauge feed of its own. Since 2026-10-21 the gauge's NWS identifier (NWSLI) is read from the H-VTEC of the warning's text product on the same API (/products), matched on the warning's P-VTEC event.
License · Public domain (US Government work)
NOAA National Water Center — modeled inundation extent
every 10 minNational Water Model analysis inundation extent — polygons per stream reach with streamflow and analysis time, simplified server-side to ~30 m. The CREST FLASH layer is wired but not read (timed out at 60 s per query, 2026-09-23). Both layers are labeled EXPERIMENTAL by the NWC.
Modeled, not observed: where the National Water Model puts water at its last analysis, for the reaches it covers. Used only inside an NWS warning polygon, as the innermost zone; a reach the model does not cover leaves the warning polygon as the only zone. Experimental per the NWC, and every ring built from it says so.
License · Public domain (US Government work)
NOAA Storm Prediction Center
every 5 minSevere weather outlooks, tornado/hail watches; rated tornado track file (EF2+ density grid, lib/geo/tornado-ef2-density.ts)
Official US severe weather authority. Convective outlook polygons and active watch geometries for tornado, hail, and wind threats.
License · Public domain (US Government work)
NOAA Storm Surge (SLOSH Model)
every 30 minStorm surge forecasts, inundation zones
NOAA Sea, Lake and Overland Surges from Hurricanes model. Rendered as a distinct surge overlay layer on hurricane events.
License · Public domain (US Government work)
NWS Storm Alerts
every 5 minTornado and severe thunderstorm warnings and watches; warnings carry the alert polygon, watches are county-based
The National Weather Service's own alert API. Warnings carry the issuing office's polygon and expiry; Calchis stores them as events and evaluates triggers against them.
License · Public domain (US Government work)
NWS Winter Weather Alerts
every 15 minWinter storm, blizzard and ice storm warnings and watches
Same NWS alert API, filtered to winter products. Ingested as events so monitored areas and triggers see them.
License · Public domain (US Government work)
NWS Fire Weather Alerts
every 30 minRed Flag Warnings and Fire Weather Watches
NWS fire-weather products, ingested as fire_weather events (never as wildfires). Zone-based products carry no polygon and sit at a state centroid, flagged approximate. A product with a polygon within 200 km of an active wildfire is also linked to that fire's timeline.
License · Public domain (US Government work)
NWS Tropical Alerts
every 15 minHurricane, Tropical Storm and Storm Surge Watches and Warnings; Extreme Wind Warnings
NWS tropical products, ingested as tropical_alert events (never as hurricanes — the storm is the NHC row). Zone-based; each is drawn from the NWS zones it names (migration 149), or sits at a state centroid, flagged approximate, when a zone cannot be resolved.
License · Public domain (US Government work)
NWS Heat and High Wind Alerts
every 30 minExtreme Heat Warnings and Watches, Heat Advisories; High Wind Warnings and Watches
NWS heat and non-convective wind products, ingested as extreme_heat and high_wind events. Zone-based; each is drawn from the NWS zones it names, or sits at a state centroid, flagged approximate, when a zone cannot be resolved. Wind Advisories are not ingested.
License · Public domain (US Government work)
State DOT Traffic Cameras
on demandCamera locations and still images near an active event; nothing is stored
A map layer, off by default, that links to state DOT 511 snapshot images near an event. Coverage is partial: on 2026-09-01 only Florida's feed returned images. Under review.
License · Terms vary by state; FL511, the only feed that answered, has terms Calchis has not readTerms not yet reviewed — Every camera system whose terms are unread is excluded from /api/v1/cameras/nearby (SYSTEM_TERMS in lib/data-sources/dot-cameras.ts), so the layer shows nothing until a system is read and marked.
Historical Data Sources
70 years of US-scoped disaster records used for frequency analysis, return period calculation, and model calibration.
| Dataset | Time Span | Records | Scope | License |
|---|---|---|---|---|
| FEMA Disaster Declarations | 1953 -- present | 68,000+ | US counties | Public domain (US Government work) |
| NOAA Storm Events Database | 1950 -- present | 1.8M+ | US states and counties | Public domain (US Government work) |
| NOAA Storm Events — hail extract | 1996 -- present | Hail reports with size, from the Storm Events CSVs | US states and counties | Public domain (US Government work) |
| IBTrACS Best Track Archive | 1842 -- present | 100,000+ track points | North Atlantic basin | Public domain (NOAA / WMO) |
| NIFC Historical Fire Perimeters | 1984 -- present | 96,000+ | US federal and state lands | Public domain (US interagency) |
| USGS Earthquake Catalog | Full history | 3M+ | CONUS + AK + HI + territories | Public domain (US Government work) |
| NOAA/AOML HRD All U.S. Hurricanes | 1851 -- present | 309 continental US hurricane strikes | Continental United States | Public domain (US Government work) |
| Iowa Environmental Mesonet ASOS archive (Iowa State University) | Varies by station; the landfall check reads 2017 -- 2024 | Airport METAR wind and gust around 23 US hurricane landfalls | Gulf and Atlantic coast states | Public domain (IEM disclaimer: "in the public domain and may be used freely by anyone for any lawful purpose") |
| NOAA NCEI Severe Weather Data Inventory — NEXRAD hail signatures | 2005 -- 2024 (as used) | NEXRAD Level-III Hail Detection Algorithm signatures: size, probability of severe hail, radar range | US radar coverage | Public domain (US Government work) |
| USDA Forest Service — Wildfire Risk to Communities | 2026 summaries (LANDFIRE 2020 fuels, FSim burn probability) | Share of homes in Direct/Indirect wildfire exposure zones, per Census place and county | 50 states (not territories) | US Government work — freely available without additional permissions or fees; cite the publicationWildfire exposure from Scott, J.H. et al., Wildfire Risk to Communities: Community Wildfire Risk Reduction Zones for the United States, USDA Forest Service Research Data Archive, RDS-2024-0030. |
| MTBS Fire Occurrence Dataset (USGS/USFS) | 1984 -- present | 1,000+ acre (500+ in the East) burn boundaries | United States | Public domain (US Government work) |
| USGS Quaternary Faults | Current release (DOI 10.5066/F7S75FJM) | Fault traces with slip rates | United States | Public domain (US Government work) |
| FEMA NFIP Claims | 1978 -- present | Aggregate by census tract | US flood insurance program | Public domain (US Government work) |
| Microsoft Building Footprints | Current release | 130M+ structures, aggregated to 84,044 tracts | United States | Open Database License (ODbL) 1.0Building counts derived from Microsoft Building Footprints (ODbL). |
Reference & Platform Sources
Geography, the map, and the catalog sources that are neither a live feed nor a historical archive — listed here because a data source you would not think to ask about is the wrong one to leave off.
| Source | Used for | License |
|---|---|---|
| NWS public forecast zone / county correlation | Which counties each NWS forecast zone covers, so a storm NCEI filed against a zone ("San Bernardino County Mountains") reaches the counties it affected on the county hazard history pages. Replaces matching NOAA's zone NAME to a county name, which reached 92.0% of records nationally but 53% in California and 6% in Alaska. | Public domain (US Government work, NOAA/NWS) |
| US Census Bureau — TIGER/Line, tracts, ACS | Census tract geography, population and housing counts for the exposure model; TIGERweb boundaries for monitored areas; the Census Geocoder resolves every stored address | Public domain (US Government work); the Data API carries its own terms of serviceThis product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau. |
| Hurricane Milton (2024) — NHC Tropical Cyclone Report and Munich Re loss figures | The one historical-loss benchmark the validation suite executes (lib/modeling/validation/milton-2024-benchmark.ts): landfall position, pressure and wind from the TCR; the reported insured (US$25bn) and overall (US$38bn) loss from Munich Re's 9 January 2025 media release. Seven hand-typed figures with citation; nothing is fetched at runtime or redistributed | NHC report: public domain (US Government work). Munich Re figures: publicly released press figures, quoted with attributionNHC TCR AL142024 (Beven, Alaka & Fritz, 2025); Munich Re, Natural disasters in 2024, media release 9 January 2025 |
| USGS National Seismic Hazard Model, conterminous U.S. 2023 (nshm-conus) — western-US fault system | Earthquake fault sources since model 3.0 (lib/modeling/generated/nshm-2023-wus-ruptures.ts and -sections.ts, generated by scripts/fetch-nshm-fault-system.ts): the branch-averaged rupture set (magnitude, annual rate, sections spanned; ruptures rarer than 1e-8 per year dropped) and the fault-section surface traces from nshm-conus version 6.2.0, commit a69e117bcde015368be1a6752773f32ffa1b968c, active-crust/fault/wus-system/branch-avg/ruptures.csv and sections.geojson (sha256 in the generated module). Downloaded once by hand; nothing is fetched at runtime | Public domain (U.S. Geological Survey work product)Powers, P.M. and Altekruse, J.M. (2022), nshm-conus: National Seismic Hazard Model for the conterminous U.S., U.S. Geological Survey software release, doi:10.5066/P9J1OVR6; Petersen et al. (2023), The 2023 US 50-state National Seismic Hazard Model, Earthquake Spectra 40(1), doi:10.1177/87552930231215428 |
| USGS 2023 NSHM (CONUS 2023.R2, Alaska 2023.R1, Hawaii 2021.R2) — uniform-hazard ground motion values, PGA 2% in 50 years, site class BC | The earthquake hazard score since model 3.6 (lib/modeling/nshm-pga.ts over lib/modeling/generated/nshm-2023-pga-2475.ts, generated by scripts/generate-nshm-pga-grid.ts): the 2%-in-50-year PGA at Vs30 760 m/s on the 0.05-degree conterminous-US grid (ScienceBase item 691dfb9ad4be02142cbce6d8), and since model 3.7 the 0.1-degree Alaska 2023.R1 grid (681bbdefd4be0260c2c45c80) and the 0.02-degree Hawaii 2021.R2 grid (6802a4fad4be0210cdcc996b, plus its test-site values as the validation yardstick); member <archive>/vs30-760/PGA/map.csv of each, sha256 in each generated module. Downloaded once by hand; nothing is fetched at runtime | Public domain (U.S. Geological Survey data release)Altekruse, J.M., Powers, P.M., and Milner, K.R. (2026), Mean Seismic Hazard Curves and Uniform-Hazard Ground Motion Values from the Revised 2023 US 50-state National Seismic Hazard Model, U.S. Geological Survey data release, doi:10.5066/P14VGAV4 |
| USGS nshmp-lib — Boore, Stewart, Seyhan & Atkinson (2014) ground-motion model, PGA coefficients and reference implementation | Active-crust earthquake site intensity since model 3.1 (lib/modeling/gmm/bssa14.ts, generated coefficients in lib/modeling/generated/bssa14-pga-coefficients.ts from scripts/data/nshmp-lib-BSSA14.csv): the BSSA14 NGA-West2 PGA model as implemented in nshmp-lib release 1.8.5 (commit 44728a7dfc880113783f352c0d8bbf0678ec8f49), src/main/resources/gmm/coeffs/BSSA14.csv and src/main/java/gov/usgs/earthquake/nshmp/gmm/BooreEtAl_2014.java. Downloaded once by hand; nothing is fetched at runtime | Public domain (U.S. Geological Survey software release)Boore, D.M., Stewart, J.P., Seyhan, E., Atkinson, G.M. (2014), NGA-West2 equations for predicting PGA, PGV, and 5% damped PSA for shallow crustal earthquakes, Earthquake Spectra 30(3) 1057-1085; coefficients and implementation as in USGS nshmp-lib (public domain) |
| NHERI SimCenter Damage and Loss Model Library — Hazus 5.1 hurricane wind loss functions; Hazus 6.1 earthquake equivalent-PGA fragilities | Hurricane building-loss curves since model 2.3 (lib/modeling/generated/hazus-hurricane-wind-curves.ts, migration 153): Hazus 5.1 hurricane wind loss functions as tabulated by NHERI SimCenter DLML (BSD-3), commit 662999759cc59bf9cfc099d4ff5a5814a7bf01c8, src/dlml/data/hurricane/building/portfolio/Hazus v5.1 original/loss_repair.csv (sha256 6f023f82c4ab56e57d0d20becf72e0c46a13cf4a80ebd28c3ac50f6bb83de222). Downloaded once by hand; nothing is fetched at runtime. Earthquake damage curves since model 2.5 (lib/modeling/generated/hazus-earthquake-pga-fragilities.ts, migration 170): Hazus 6.1 equivalent-PGA structural fragilities and repair-cost ratios, commit 192d28020cafaa4a3bba9fb7340bedef593780f7, src/dlml/data/seismic/building/portfolio/Hazus v6.1/fragility.csv (sha256 4746c12744c9083c069ca161e5825de0d686d42ea4cdab7143d5e9ff75cbc505) and consequence_repair.csv (sha256 2ea57a6333240e6a0593eb7401ff62169d637136624c0b8e66c8a79967a9dd48); same terms | BSD-3-Clause (SimCenter's tabulation); the FEMA Hazus data inside it is US Government work product, public domain in the United States (17 U.S.C. §105), with no separate terms statedHazus 5.1 hurricane wind loss functions and Hazus 6.1 earthquake fragilities as tabulated by NHERI SimCenter DLML (BSD-3); Copyright (c) 2023, Leland Stanford Junior University and The Regents of the University of California |
| USGS 3D Elevation Program — Elevation Point Query Service | Ground elevation at a scored point, feeding storm-surge exposure and the flood elevation component (1/3 arc-second DEM, ~10 m) | Public domain (US Government work) |
| FEMA National Flood Hazard Layer (NFHL) | Flood zone at a scored point, and the base flood elevation the flood 'elevation above base flood level' component is scored on (static BFE on the zone polygon where FEMA published one; otherwise the nearest published BFE contour) | Public domain (US Government work) |
| NOAA VDatum | NGVD29 → NAVD88 vertical offset at a point, so a base flood elevation FEMA published on the older datum can be compared with NAVD88 ground elevation (one lookup per ~1 km cell; the offset and its uncertainty are recorded on the point) | Public domain (US Government work) |
| USGS National Structures Dataset (via HIFLD / Esri U.S. Federal Data) | Critical infrastructure overlay: hospitals, EMS, fire stations and schools within range of an event (four layers, 175,873 records) | CC BY 4.0, credit U.S. Geological Survey — verified per layer 2026-09-01Critical infrastructure: USGS National Structures Dataset, via Esri U.S. Federal Data (CC BY 4.0). |
| OpenStreetMap (via Overpass API) | Lifeline infrastructure the federal open layers do not cover: electric substations, water and wastewater treatment plants, and communication towers. CROWD-SOURCED, not authoritative — a facility absent from OSM is not evidence that no facility is there, and rows are labeled accordingly wherever they are shown. | Open Database License (ODbL) 1.0Lifeline infrastructure (substations, water treatment, communication towers) © OpenStreetMap contributors, available under the Open Database License (ODbL). |
| NLCD Land Cover | Land-cover composition per tract (NLCD 2021); caps structure estimates in developed vs undeveloped land | Public domain (US Government work) |
| Natural Earth | Coastline for coastal-proximity scoring | Public domain |
| US Bureau of Economic Analysis — Regional GDP | County gross domestic product for the economic-exposure endpoints (what a county produces, beside what it pays) | Public domain (US Government work); the Data API carries its own terms of serviceThis product uses the Bureau of Economic Analysis (BEA) Data API but is not endorsed or certified by BEA. |
| US Bureau of Labor Statistics — QCEW | County employment and wages by industry (Quarterly Census of Employment and Wages) for the economic-exposure endpoints | Public domain (US Government work); BLS asks to be cited as the sourceSource: U.S. Bureau of Labor Statistics, Quarterly Census of Employment and Wages. |
| FCC Area API — census block lookup | Coordinate → census block and tract when the Census geocoder is unavailable (fallback only) | Public domain (US Government work) |
| Mapbox GL, tiles and Static Images | Map rendering, satellite imagery, and address suggestions while you type. Suggestions are shown, never stored — stored coordinates come from the Census Geocoder | Mapbox Terms of Service and Product Terms (commercial)© Mapbox © OpenStreetMap |
| Mapbox Geocoding v5 (temporary) | Address suggestions while you type, shown and discarded. Nothing from it is stored: the coordinate written to a portfolio or monitored area comes from the Census Geocoder | Mapbox Terms of Service and Product Terms (commercial); results may be displayed, not stored© Mapbox © OpenStreetMap |
| Artemis Deal Directory | Leads for the cat bond catalog. Each entry passes an automated promotion check (no hand review), keeps its source link, and is served only to signed-in users. The ingest is paused pending a license, and the catalog can be switched off and removed without affecting a customer's own positions or triggers | Commercial publisher; terms under legal reviewSource: Artemis Deal Directory — every catalog entry keeps its source linkTerms not yet reviewed — No terms page was found on the site (2026-09-04); with counsel (register F2). Until answered the catalog is sign-in only, not indexed, and never exported. |
| Bitcoin block headers (public explorers) | Confirming a digest anchor: the merkle root and time of the block an OpenTimestamps proof names (lib/determination/anchor/ots.ts). Three fields of one public-ledger header per anchor, a few a day; blockstream.info first, mempool.space when it does not answer | Public-ledger data read through a free, keyless API. Blockstream publishes its hosted explorer's terms only behind the Explorer API account sign-in (the Esplora code is MIT; the hosted service's terms are not public); mempool.space's public API is stated non-commercial, so it is the fallback onlyTerms not yet reviewed — What is fetched is a block hash, a merkle root and a timestamp — facts of a public ledger that any node reports identically — and what is stored is those three fields on the anchor row. No dataset is held or redistributed. Terms looked for on 2026-11-06: Blockstream's hosted explorer terms are shown only on creating an Explorer API account and are not published; mempool.space states its public API is for non-commercial use, so it is the fallback only. The proof file itself verifies against any Bitcoin node without either explorer, which is the fallback of record. Confirm Blockstream's hosted terms by creating an account, or run the confirmation against a node, before relying on the explorer commercially. |
Scoring Model Sources
Published research and government technical manuals that calibrate our hazard scoring models. Coefficients cite their source references where established.
USGS NSHM 2023
Seismic hazard parameters, Gutenberg-Richter a/b values, fault geometry
Petersen, M.D., et al. (2024). The 2023 US 50-State National Seismic Hazard Model: Overview and implications. Earthquake Spectra 40(1).
Use · Public domain (US Government work)Petersen et al. (2024), The 2023 US 50-State National Seismic Hazard Model, Earthquake Spectra 40(1), doi:10.1177/87552930231215428
FEMA Hazus v6.1
Vulnerability functions, depth-damage curves, construction type damage ratios
FEMA (2024). Hazus Earthquake/Hurricane/Flood Model Technical Manuals v6.1 / v5.1.
Use · Public domain (US Government work)FEMA Hazus Technical Manuals (earthquake, hurricane, flood)
Kaplan & DeMaria (1995)
Hurricane wind decay after landfall
Kaplan, J. & DeMaria, M. (1995). A Simple Empirical Model for Reducing Tropical Cyclone Intensity After Landfall. Journal of Applied Meteorology.
Use · Published work; cited parameter values used as facts, no text reproducedKaplan & DeMaria (1995), J. Appl. Meteor. 34Terms not yet reviewed — Only the published parameter values and equations are used, with this citation beside them; the article itself is not copied or redistributed.
Abatzoglou & Williams (2016)
Cited in the wildfire methodology; the 1.4× frequency multiplier once attributed to it was retired 2026-09-04
Abatzoglou, J.T. & Williams, A.P. (2016). Impact of anthropogenic climate change on wildfire across western US forests. PNAS 113(42). DOI: 10.1073/pnas.1607171113
Use · Published work; cited parameter values used as facts, no text reproducedAbatzoglou & Williams (2016), PNAS 113(42)Terms not yet reviewed — Only the published parameter values and equations are used, with this citation beside them; the article itself is not copied or redistributed.
Brooks et al. (2003)
Tornado frequency climatology, EF2+ spatial distribution
Brooks, H.E., Doswell, C.A., & Kay, M.P. (2003). Climatological Estimates of Local Daily Tornado Probability for the United States. Weather and Forecasting 18.
Use · Published work; cited parameter values used as facts, no text reproducedBrooks, Doswell & Kay (2003), Wea. Forecasting 18Terms not yet reviewed — Only the published parameter values and equations are used, with this citation beside them; the article itself is not copied or redistributed.
Data Quality Commitments
Every ingested record stores: source, source_url, ingested_at, confidence_score.
Every model parameter references its source publication with source_description, validation_note, and effective_date.
Workers never crash the application. A failed source returns empty data gracefully -- no cascading failures.
3+ consecutive failures on any data source trigger automated Sentry alerts for immediate investigation.
Every hazard score exposes all sub-components in score_components. No black boxes.
Model parameter changes are logged with old_value, new_value, change_rationale, and supporting_paper_ids.
Most sources listed are US Government works in the public domain; the ones that are not carry their license and the attribution we owe above. Calchis does not modify source data — raw records are stored alongside derived outputs for full auditability. For situational awareness only — not for emergency response.