Deforestation alert
A near-real-time notification generated when satellite data indicate probable forest loss in a specific area.
Alert systems compare new imagery against a reference condition and flag cells where the change signature matches forest loss. They are designed for speed rather than precision, so an alert is an indication, not a confirmed finding.
Operationally, alerts are the front line of enforcement and monitoring. They direct field inspection, trigger verification of reported incidents and can suspend crediting where loss is found inside a project boundary. The value depends on latency: an alert that arrives six months late cannot prevent the damage.
Every alert system carries both false positives — cloud artefacts, harvest that was permitted, seasonal flooding — and false negatives, particularly for degradation, small clearings and loss beneath cloud or smoke. Pairing alerts with radar and higher-resolution review is what makes them usable.
Frequently asked questions
Does an alert prove deforestation occurred?
No. It indicates probable loss and requires confirmation from imagery review or field inspection.
How quickly are alerts produced?
Good systems deliver within days of acquisition; slower systems lose most of their operational value.