How severity and locations are derived
Severity bands are this app's own normalisation of each source's rating. USGS: M7.0 and above Critical, M6.0 to 6.9 High, M5.0 to 5.9 Medium, below M5.0 Low. GDACS: Red Critical, Orange High, Green Low. NASA EONET storms by sustained wind: 113 kt and above Critical, 64 kt High, 34 kt Medium. Every other record is Not rated because its source publishes no comparable rating. The source's own rating is always shown in the event detail.
ReliefWeb lists disasters with an alert or ongoing status, so they appear in every time window and show the date the event began. Their markers sit at the country centroid of the primary country, not at an incident site. GDELT markers show places named in news coverage, so they measure media attention and are not a count of verified incidents. Records from different feeds that describe the same hazard within a short distance and time are merged, keeping the higher-priority source (GDACS, then USGS, then NASA EONET).
OCHA HAPI feeds are monthly or periodic country-level aggregates, not live incident feeds. Conflict counts are ACLED-coded events for the latest complete month, including demonstrations. About two dozen countries, among them Sudan, Ukraine, Myanmar, Syria, Yemen and DR Congo, publish only sub-national rows, so the app takes the most complete administrative level per country and never adds levels together. Displacement is IOM DTM: assessments overlap geographically, so the app shows the largest single assessment and does not sum them. Food insecurity is the IPC Phase 3 or worse population from the latest current analysis. All three are placed at the country centroid, and marker size scales with the reported count on a logarithmic scale.
Reports are ReliefWeb documents that carry at least one ReliefWeb theme, filtered by the time ReliefWeb posted them. A report is mapped once, at the centroid of its primary country, even if it covers several countries or a whole region. Reports whose primary country has no coordinates are listed but not mapped. All ReliefWeb formats are included (situation reports, news and press releases, analyses, assessments, maps, infographics, appeals and others); filter by format in the Reports tab. When more reports exist than the app loads, the Feeds panel says how many were loaded and how far back they reach.