Data, definitions & methods

The two core datasets

Oil spill records come from the NOSDRA Oil Spill Monitor. The two published spill URLs return the same dataset in the captured snapshot, so records are deduplicated rather than counted twice.

Gas flare values and geographic layers come from the Nigeria Gas Flare Tracker. State, LGA, cluster, block, company and onshore/offshore aggregations are presented independently.

Time means two different things

Observation date is the incident date or flare month in a source row. Retrieval date is when this product fetched the endpoint. A successful fetch today does not make an older observation current.

Missing values

A missing spill quantity is displayed as “not supplied,” because the exact quantity cannot always be ascertained. It is never converted to zero.

For gas flaring, a covered state or LGA with no row in a successfully retrieved period is described as “no flaring detected by the tracker for this period.” This wording fits both non-producing areas and areas where the tracker did not detect flaring; it does not make a broader geological claim.

Offshore locations

Coordinates outside Nigeria's land boundary can still be valid offshore incidents or flare sites. The map is designed to show the adjacent Gulf of Guinea rather than rejecting such records.

Block name matching

The flare time series and polygon layer sometimes use different names. A historical prospecting licence may later become a mining lease, while polygons may use lettered subdivisions or field names. We show verified lineage, but do not pretend those labels define identical boundaries. Unconfirmed joins are labelled location not matched.

Company history

Company flare data is included through October 2020—the final supplied month. It remains useful historically, but is never presented as a current company ranking.

Population layer

Where shown, the label is estimated population living within 2 km of flare locations and the value is reproduced from the tracker layer. The product does not convert it into an “affected population” estimate.

What this product does not do

• No predictive model, risk score or AI-generated environmental conclusion.
• No penalties, emissions conversions or health-impact calculations without a verified source and method.
• No authentication, private workspaces or user-uploaded evidence.