Methodology

What the monitor shows

The monitor presents satellite-observed active-fire detections and thermal anomalies assigned to Ghana's governed district and agro-climatic-zone units before publication. A displayed point is the centre of a detected satellite pixel. The browser displays published assignments and does not perform spatial joins or reassign records.

Near-real-time processing

The private ingestion system processes governed MODIS and Suomi-NPP VIIRS source snapshots and publishes 24-hour and 48-hour views from one accepted snapshot. A single-sensor release may be published when the other source fails. If both sources fail, the public monitor retains the last accepted release rather than fabricating new observations.

The browser fetches the mutable live pointer without cache, validates the immutable release metadata and loads only the selected rolling-window GeoJSON. Pointer checks run no faster than the governed 30-minute ingestion cadence. This is periodic near-real-time publication, not continuous streaming.

Historical processing

Historical mode uses standard processed MODIS and Suomi-NPP VIIRS products. It loads the governed date catalogue and then at most one daily JSON shard for the selected UTC date. A valid observed date with zero retained detections remains distinct from a date with missing source observations or a date before a sensor's structural support.

Map and filtering method

The boundary-only map uses locally hosted MapLibre GL JS. Ghana and agro-climatic-zone polygons load at map initialisation; district boundaries load only when enabled. The same filtered record population drives summary cards, map points, the table, CSV and GeoJSON exports. Clustering changes presentation with zoom but does not alter record counts or scientific meaning.

Time authority

Acquisition, publication and window times use Coordinated Universal Time (UTC). Historical date strings are treated as governed UTC product dates and are not shifted by the browser timezone. Ghana local time may be used only as an explicitly labelled presentation aid; it is not the storage or filtering authority.