GLAD Deforestation Alerts — Satellite Monitoring Cuts Central African Forest Loss by 18%

Global Forest Watch's GLAD (Global Land Analysis and Discovery) alert system, developed by the University of Maryland and hosted by the World Resources Institute, publishes free satellite-derived tree-cover-loss alerts roughly every eight days across the tropics. In Cameroon, government forestry officials use the alerts to flag unauthorised logging inside forest titles and concessions, while civil-society monitors use the same open data to independently report suspected illegal clearing to authorities — the same pattern documented in the neighbouring Central African Republic.

A peer-reviewed econometric evaluation (Moffette, Alix-Garcia, Shea et al., "The impact of near-real-time deforestation alerts across the tropics", Nature Climate Change, 2021) compared deforestation trends in areas with active alert subscriptions against similar unmonitored areas across 22 tropical countries, controlling for altitude, soil type, distance to roads and ports, and macroeconomic trends. It found deforestation fell by roughly 18% relative to the 2011–2016 baseline in the areas where the effect was statistically significant — Central Africa, including Cameroon and the Central African Republic — equivalent to an estimated 50,000 hectares of avoided deforestation per year across the monitored regions, roughly three times the land area of Washington, D.C. The authors note their design was built to find the minimum plausible effect, so the true impact may be larger; effectiveness was strongest inside protected areas and logging concessions where enforcement follow-up was already possible, and results in South America and Asia were not statistically significant, likely reflecting competing monitoring tools or lower uptake.

The practice is a governance and enforcement tool rather than a direct restoration or payment scheme: it does not itself sequester carbon or restore habitat, but by making illegal clearing visible in near real time it strengthens the enforcement backbone that PES and REDD+ programmes elsewhere in the catalogue depend on.

Read the full analysis: https://globalnaturewatch.org/blog/data/glad-alerts-reduce-deforestation-africa/