SRTM C Band (1 arc-second)

Free

Provider: NASA / USGS
Mission Date: February 11–22, 2000
Instrument: C-band Interferometric Synthetic Aperture Radar (InSAR)
Release: Public global access since 2014 (SRTMGL1 product)

Specification

Coverage Area : Nearly global: 60°N to 56°S (covers ~80% of Earth's land surface)

Spatial Resolution : 1 arc-second (~30 meters at the equator)

Vertical Accuracy : ±16 m (absolute), ±6 m (relative), varies by terrain/vegetation

Horizontal Datum : WGS 84 (EPSG:4326)

Vertical Datum : EGM96 geoid

File Format : GeoTIFF

Tile Size : 1° x 1°

Elevation Units : Meters above mean sea level

Data Type : 16-bit signed integer

Acquisition Method : Interferometric SAR via dual antennas on Shuttle Endeavour

Data Voids : Present in rugged terrain or dense vegetation; mostly filled in V3 release

Data Version : SRTMGL1 v3 (void-filled global release, 2014)

Access / Licensing : Public domain; downloadable via USGS EarthExplorer, NASADEM, or AWS Open Data