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Full catalog/SRTMIMGM
SRTMIMGM·v003·dataset

Radar-mapped images of Earth's terrain (Shuttle SRTM)

NASA Shuttle Radar Topography Mission Combined Image Data Set V003
land NASA LPCLOUD Level 3 Binary
In plain English

What it measures. This is a seamless global mosaic of radar images of Earth's terrain at about 30 m detail, showing uncalibrated radar brightness rather than precise scattering values. Many overlapping radar looks were averaged together to make a smooth picture.

How it's made. It comes from the Shuttle Radar Topography Mission flown aboard the Space Shuttle in 2000, with one-degree tiles merged and averaged into a single image product by NASA's LP DAAC.

How & where you'd use it. Useful as a global terrain backdrop for mapping and visualization. A companion swath product preserves the detailed scattering values for quantitative radar analysis.

What's measured

SPECTRAL/ENGINEERING › RADAR › RADAR IMAGERYLAND SURFACE › TOPOGRAPHY › TERRAIN ELEVATIONLAND SURFACE › TOPOGRAPHY › TERRAIN ELEVATION › TOPOGRAPHICAL RELIEF MAPS

Coverage & cadence

  • Time span2000-02-11 → 2000-02-21
  • Measured bySTS-99 (SRTM)
  • Processing levelLevel 3
  • Spatial extent-180, -56, 180, 60
  • FormatsBinary
  • StatusCOMPLETE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The Land Processes Distributed Active Archive Center (LP DAAC) is responsible for the archive and distribution of NASA Making Earth System Data Records for Use in Research Environments ([MEaSUREs](https://earthdata.nasa.gov/about/competitive-programs/measures )) SRTM, which includes the global 1 arc second (~30 meter) combined (merged) image data product. (See User Guide Section 2.2.2) The combined image data set contains mosaicked one degree by one degree images/tiles of uncalibrated radar brightness values at 1 arc second. To create a smooth mosaic image, each pixel in an output is an average of all the image pixels for a location. Pixels with a value of zero (voids) were not counted. Because SRTM imaged a given location with two like-polarization channels (VV = vertical transmit and vertical receive, and HH = horizontal transmit and horizontal receive) and at a variety of look and azimuth angles, the quantitative scattering information was lost in the pursuit of a smoother image product unlike the SRTM swath image product [SRTMIMGR](https://doi.org/10.5067/MEaSUREs/SRTM/SRTMIMGR.003), which preserved the quantitative scattering information. The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence Agency (NGA - previously known as the National Imagery and Mapping Agency, or NIMA), as well as the participation of the German and Italian space agencies. This collaboration aims to generate a near-global digital elevation model (DEM) of Earth using radar interferometry. SRTM was the primary (and virtually only) payload on the STS-99 mission of the Space Shuttle Endeavour, which launched February 11, 2000 and flew for 11 days. The SRTM swaths extended from ~30 degrees off-nadir to ~58 degrees off-nadir from an altitude of 233 kilometers (km), creating swaths ~225 km wide, and consisted of all land between 60° N and 56° S latitude to account for 80% of Earth's total landmass. Known Issues * Known issues in the NASA SRTM are described in the following publication: * Rodriguez, E., C. S. Morris, and J. E. Belz (2006), A global assessment of the SRTM performance, Photogramm. Eng. Remote Sens., 72, 249–260. https://doi.org/10.14358/PERS.72.3.249

Get the data

srtmimgm_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SRTMIMGM",
    version="003",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LPCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.