Ghost projects from space

Two checks from orbit on the projects we track. At night: is anyone switching lights on at projects that should already be finished? By day: has anything visibly changed on the site in the last quarters? Both run every week on open data, for every tracked project whose location we know from public sources. Coordinates stay private; the figures below are rounded and listed by anonymous case id.

Proxies, not proof. Light at night is not occupancy: an empty building can keep its common areas lit, and a lived-in villa among trees can look dark. No visible change from space is not a stalled project: interior work does not show at 10 m. Use these as reasons to ask for a site visit, not as verdicts.

…loading

…

1. Night lights where the project should be finished

NASA Black Marble, daily night-time radiance at about 460 m, corrected for moonlight and filled across cloudy nights. For each project we compare the pixels on the pin with the ring around it, and the last 12 months with the 12 before.

Loading…

2. Visible change on site, every project with coordinates

Sentinel-2 at 10 m, a 150 m circle around each pin, one cloud-free composite per quarter. We count the share of pixels that visibly changed between consecutive clear quarters, after removing the shift the whole area shows (sun angle, haze, season). The column on the right says how long the site has looked the same.

Loading…

Sources, method and limits

Night lights

Source: NASA Black Marble VNP46A2 (VIIRS on Suomi NPP), read through the NASA GIBS map service, which needs no login. NASA data has no restrictions on use.
The raw HDF5 files on LAADS DAAC need an Earthdata login, so we do not use them. GIBS serves the same product as colour bins of 0.1 nW/(cm² sr) at the low end, saturating at 38.2: values here are bin midpoints.
Four nights a month (the 1st, 8th, 15th and 22nd) for 36 months, a 25 by 25 pixel window on the pin. Pin: the 3 by 3 pixels around it (about 1.4 km). Surroundings: pixels 1.9 to 5.5 km away.
One pixel is wider than most projects, so neighbours, roads and street lights count too.

Visible change

Source: Copernicus Sentinel-2 L2A from AWS Open Data, found with the Element84 Earth Search catalogue. Free and open, no paid imagery.
Per quarter, up to two scenes that see at least 90% of the circle without cloud, per-pixel median. A pixel changed if its brightness moved by more than 25 of 255, or it switched between built-up or bare and vegetated.
A pair of quarters with 10% or more changed pixels counts as visible change. The threshold is high on purpose: wet and dry seasons move pixels too.
Finished buildings should look unchanged. A site where only interiors are being fitted out also looks unchanged.

Data: /data/night-lights.json and /data/stalled-sites.json (weekly, full method and limits inside). Contains modified Copernicus Sentinel data. Black Marble: Román et al. 2018, Remote Sensing of Environment 210. Related: satellite watch of 27 areas with monthly timelapses, and natural hazards at any pin.