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Full catalog/GWELDMO
GWELDMO·v031·dataset

Cloud-free monthly Landsat land mosaics (30 m)

NASA Global Web-Enabled Landsat Data Monthly Global 30 m V031
land NASA LPCLOUD Level 2 HDF-EOS2
In plain English

What it measures. Monthly, nearly cloud-free mosaics of land surface across the globe at 30 m, including surface color bands, a vegetation greenness index (NDVI), and how warm the thermal bands appear at the top of the atmosphere.

How it's made. Assembled from all available Landsat 4, 5, and 7 imagery for the 1985, 1990, and 2000 time periods, processed onto a grid that matches NASA's MODIS land tiles.

How & where you'd use it. Provides consistent imagery for mapping land cover and tracking how landscapes have changed across regions over decades.

What's measured

LAND SURFACE › LAND USE/LAND COVERLAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCEBIOSPHERE › VEGETATION › VEGETATION INDEX › NORMALIZED DIFFERENCE VEGETATION INDEX (NDVI)

Coverage & cadence

  • Time span1984-03-01 → 2001-11-30
  • Measured byLANDSAT-7 (ETM+) · LANDSAT-5 (TM) · LANDSAT-4 (TM)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • 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 NASA Making Earth System Data Records for Use in Research Environments ([MEaSUREs](https://earthdata.nasa.gov/about/competitive-programs/measures)) Global Web-Enabled Landsat Data Monthly (GWELDMO) Version 3.1 data product provides Landsat data at 30 meter (m) resolution for terrestrial non-Antarctica locations over monthly reporting periods for the 1985, 1990, and 2000 epochs. GWELD data products are generated from all available Landsat 4 and 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) data in the U.S. Geological Survey (USGS) Landsat archive. The GWELD suite of products provide consistent data to derive land cover as well as geophysical and biophysical information for regional assessment of land surface dynamics. The GWELD products include Nadir Bidirectional Reflectance Distribution Function (BRDF)-Adjusted Reflectance (NBAR) for the reflective wavelength bands and top of atmosphere (TOA) brightness temperature for the thermal bands. The products are defined in the Sinusoidal coordinate system to promote continuity of NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) land tile grid. Provided in the GWELDMO product are layers for surface reflectance bands 1 through 5 and 7, TOA brightness temperature for thermal bands, Normalized Difference Vegetation Index (NDVI), day of year, ancillary angle, and data quality information. A low-resolution red, green, blue (RGB) browse image of bands 5, 4, 3 is also available for each granule. Known Issues * GWELDMO known issues can be found in Section 4 of the Algorithm Theoretical Basis Document (ATBD).

Get the data

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

results = earthaccess.search_data(
    short_name="GWELDMO",
    version="031",
    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.