SRTMbased

SRTMbased refers to datasets, analyses, or products that are derived from the Shuttle Radar Topography Mission (SRTM) digital elevation model. The term is used in GIS and remote sensing to indicate that SRTM data were the primary source of elevation information, as opposed to other DEM sources such as GTOPO30 or ASTER.

SRTM, launched in 2000, produced nearly global topographic data. In practice, SRTMbased products typically come in two widely used resolutions: about 30 meters (1 arc-second) and about 90 meters (3 arc-seconds), with coverage spanning most land areas between roughly 60 degrees north and 56 degrees south. The data are released in the public domain by NASA and USGS.

Applications of SRTMbased products include terrain analysis (slope, aspect, hillshading), watershed and hydrological modeling, flood risk assessment, geomorphology, and landform mapping. They are commonly used as a baseline for other geospatial analyses and as a reference layer in standardized GIS workflows.

Limitations include data voids and gaps, especially in rugged or vegetated terrain and near water bodies; polar regions are not covered by SRTM data; radar-based elevations may reflect vegetation canopies in some environments, requiring ground- or vegetation-aware processing; and generalization or resampling is common when integrating with higher-resolution layers or different datums. Users often perform void-filling, reprojection, or datum conversion when creating SRTMbased products.

Availability: SRTM data are widely accessible from public portals (NASA, USGS) and are frequently used as baselines for terrain visualization and hydrological studies. The term “SRTMbased” thus marks a family of products where SRTM serves as the foundational elevation source.