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Full catalog/GWELDMO
GWELDMO·v032·dataset

Stitched monthly Landsat land imagery (30 m, v32)

NASA Global Web-Enabled Landsat Data Monthly Global 30 m V032
land NASA LPCLOUD Level 2 HDF-EOS2
In plain English

What it measures. Monthly, gapless 30-meter pictures of land worldwide for the 2005 period, including surface color across several light bands, a thermal brightness measure, and a vegetation greenness index.

How it's made. Stitched together from all available Landsat 5 and Landsat 7 imagery, corrected for atmosphere and viewing angle, and arranged on a MODIS-compatible map grid.

How & where you'd use it. Provides a consistent source for mapping land cover and studying land-surface change at fine detail across regions.

What's measured

LAND SURFACE › LAND USE/LAND COVERBIOSPHERE › VEGETATION › VEGETATION INDEX › NORMALIZED DIFFERENCE VEGETATION INDEX (NDVI)LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2003-12-01 → 2006-11-30
  • Measured byLANDSAT-7 (ETM+) · LANDSAT-5 (TM)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusACTIVE

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 3.2 data product provides Landsat data at 30 meter (m) resolution for terrestrial non-Antarctica locations over monthly reporting periods for the 2005 epoch. GWELD products are generated from all available Landsat 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 provides a consistent data source 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 1-5 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 * GWELDYR Version 3.2 known issues can be found in Section 4 of the Algorithm Theoretical Basis Document (ATBD). * Within the CFMask_State layer, the valid range is listed in the granule metadata as 0 to 65534 which includes the fill value. To avoid inclusion of the fill value, the valid range should be considered 1 to 65534 as reflected in the Data Layers Characteristics table above. * Within the CFMask_State layer, the bit flag descriptions include a description for bit 0 that contradicts the listed fill value. In the description, bit 0 is stated as 1 when fill value is present, which prevents the use of 0 as the fill value. To avoid errors when using the CFMask_State layer, bit 0 should be ignored as an indicator of fill value.

Get the data

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

results = earthaccess.search_data(
    short_name="GWELDMO",
    version="032",
    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.