*2.2. Data Used*

Data used in this study included Landsat TM, ETM+ (Enhanced Thematic Mapper Plus), OLI (Operational Land Imager) satellite imagery, land-cover reference data, and vector data. The satellite images are from Landsat 5, 7, and 8 sensors with a spatial resolution of 30 m, which have been archived in the GEE (Table 1). Image selections were made for the level-1 scenes, which are the best quality images in terms of radiometric consistency and atmospheric correction [37]. These are surface reflectance data that were accompanied by meta-data and per-pixel quality information, which was intercalibrated between different Landsat sensors, and are considered suitable for time-series processing analysis [38].


**Table 1.** Information on Landsat images that were entered into composites from 1985 to 2020.

Land cover reference data consisted of data that were collected in the field, points that were sampled on image composites, and high-resolution Google Earth images. During the field campaign that was conducted from October 2020 to February 2021, we sampled 101 land occupancy points on the ICESat (Ice, Cloud, and land Elevation Satellite) data footprints, 303 points on the ICESat-2 data footprints, and 114 points elsewhere. These ICESat and ICESat-2 footprint data are dendrometric data that are intended for further studies on estimating aboveground biomass. Given that the land occupancies of these sites were known, they were used with other data as references for training and validation of classifications that were made during this study. Vector data mainly concerned forest areas, administrative regions, ecological zones, and jurisdictional boundaries in Togo. Large-scale

international boundary data for Togo (i.e., the study area) that were also available in the GEE were used for delineation during the selection of these images and the final mapping.
