Rapid monitoring of global land change
Amy Pickens, Matthew C. Hansen, Zhen Song, Andrew Poulson, Anna Komarova, Antoine Baggett, Theodore Kerr, Aleksandra Mikus, Caroline Domínguez, Alexandra Tyukavina, Annamaria Lima
Abstract
Direct human action, principally land use expansion, and natural dynamics, such as fire and drought, drive global land change. Here we present a global land change monitoring system, DIST-ALERT, that rapidly tracks vegetation loss anomalies with 30 m resolution using imagery from Landsat 8/9 and Sentinel-2A/B/C satellites. The alerts capture agricultural expansion, urbanization, logging, mining, fire, drought, landslides, and other dynamics, but without attribution. Identified through a probability sample, 2023 anthropogenic land use conversions totaled 28.6 ± 7.6 Mha (±standard error), half of which replaced long-lived or secondary natural vegetation. Fires resulting in land cover conversion totaled 14.9 ± 4.3 Mha (±standard error). Combined, these dynamics equal 0.3% of the global land surface, equivalent to the area of the state of California. Annual DIST-ALERT summaries of land use expansion and climate-driven land change can serve as a future long-term global environmental data record. An operational satellite-based monitoring system using NASA/USGS and ESA imagery enables rapid tracking of global land change, with the area of conversion due to direct human action and fire equaling the size of California in 2023.