Ten Years of Terra-i: what a pioneering Deforestation Alert System teaches us about sustaining open access monitoring

This impact brief reviews a decade of Terra-i, a pan-tropical deforestation alert system launched in 2012 by CIAT (now the Alliance of Bioversity International and CIAT) with The Nature Conservancy, HEIG-VD and King's College London. The evaluation combined a review of 76 Terra-i-related publications (40 peer-reviewed articles citing it directly) with two anonymous surveys of trained technical staff (32 responses) and registered data users (81 responses). Terra-i reached 6,907 registered users and 905 training participations, and its methodology has been cited 1,290 times through the publications that reference it. Users reported faster access to land-cover change data, more use of satellite data in reports, and effects on institutional workflows. Limited spatial resolution was the main constraint, and new registrations fell sharply after data updates stopped in 2023. Sustained use depended less on the technology than on stable teams, clear ownership and continuity through staff and political turnover (Colombia and Peru versus Honduras). The brief recommends investing in open methods early, funding routine updates and not only development, planning for succession, designing for interoperability with national systems, prioritizing higher spatial resolution, and evaluating newer supply-chain tools such as Terra-i+ separately.