Spatial density grid (heatmap) of position and vessel counts per lat/lon cell within an area. Shows where traffic concentrates. AREA REQUIRED — pass bbox, near, or near_gem_id. Requires a plan with Maritime intelligence access (can_use_maritime) — the Corporate & Supply Chain plan and above.
Historical / baseline surface: reads raw AIS positions directly. Forward-accruing: positions begin at launch (June 2026) — no historical backfill. Terrestrial AIS only (no satellite). Date windows are capped at 7 days; defaults to the trailing 1 day.
GDELT Cloud API key. Send as Authorization: Bearer gdelt_sk_....
Bounding box filter: minLon,minLat,maxLon,maxLat (lon-first axis order). One of bbox / near / near_gem_id is required.
Point 'lat,lon' for a radius area; combine with radius_km (default 50 km). One of bbox / near / near_gem_id is required.
GEM energy-asset gem_id center — concentration of traffic within radius_km of that asset (default 25 km). One of bbox / near / near_gem_id is required.
Radius in km for near / near_gem_id. Default 50 (near) or 25 (near_gem_id); clamped 1–2000.
Grid cell size in degrees (0.01–1). Smaller = finer heatmap. Defaults to 0.05.
0.01 <= x <= 1Window start YYYY-MM-DD (≤7-day window).
Window end YYYY-MM-DD.
Trailing N-day window (1–7). Defaults to 1.
1 <= x <= 7Grid cells per page (1–5000), densest first.
1 <= x <= 5000Density grid, densest cells first. Envelope: { success, cell_deg, data, pagination, applied_filters }. Each data row: cell_lat, cell_lon (cell SW/lower corner, degrees), positions (AIS message count), vessels (distinct mmsi).