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Description

The NASA Making Earth System Data Records for Use in Research Environments (MEaSUREs) Global Web-Enabled Landsat Data Annual (GWELDYR) Version 3.1 data product provides Landsat data at 30 meter (m) resolution for terrestrial non-Antarctica locations over annual 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 GWELDYR 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

  • GWELDYR known issues can be found in Section 4 of the Algorithm Theoretical Basis Document (ATBD).

Version Description

GWELD Version 3.1 data products utilize Landsat Collection 1 products as inputs which have improved per pixel cloud mask, new quality data, improved calibration information, and improved product metadata that enable view and solar geometry calculations.

Product Summary

Platforms
LANDSAT-7 ,
LANDSAT-5 ,
LANDSAT-4
Instruments
ETM+ ,
TM
Spatial Extent

N: 90 S: -90 E: 180 W: -180

Spatial Resolution
30 Meters x 30 Meters
Location
GLOBAL LAND
Coordinate System
CARTESIAN
Granule Spatial Representation
GEODETIC
Temporal Extent
1984-01-01 to 2001-12-31
Temporal Resolution
1 Year
Data Partner
Land Processes Distributed Active Archive Center (LP DAAC) ,
Geographic Information Science Center of Excellence, South Dakota State University (SD-STATE/GISCCE)
Concept ID
C2763268459-LPCLOUD
Data State
COMPLETE
Number of Files/Granules
60207
Processing Level
2
Published
Updated
Science Keywords
Land Use/Land Cover ,
Normalized Difference Vegetation Index (NDVI) ,
Reflectance

Citation

Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.

Copy Citation

Roy, D., & Zhang, H. (2019). NASA Global Web-Enabled Landsat Data Annual Global 30 m V031 [Data set]. NASA Land Processes Distributed Active Archive Center. https://doi.org/10.5067/MEASURES/GWELD/GWELDYR.031 Date Accessed: 2026-02-14

File Naming Convention

L57.Globe.annual.2001.hh11vv05.h5v1.doy004to364.NBAR.v3.1.hdf

The filename begins with the Landsat Sensor (L57), followed by the Geographic Region (Globe), the Temporal Resolution and acquisition period monthMM.YYYY (annual.2001), MODIS Grid Coordinates (hh10vv05), WELD Grid Coordinates (h5v1), Julian Date Range present in tile (004to364), Data Product Version (3.1), and the Data Format (hdf).

Documents

Publications Citing This Dataset

Variables

The table below lists the variables contained within a single granule for this dataset. Variables often contain observed or derived geophysical measurements collected from a variety of sources, including remote sensing instruments on satellite and airborne platforms, field campaigns, in situ measurements, and model outputs. The terms variable, parameter, scientific data set, layer, and band have been used across NASA’s Earth science disciplines; however, variable is the designated nomenclature in NASA’s Common Metadata Repository (CMR). Variable metadata attributes such as Name, Description, Units, Data Type, Fill Value, Valid Range, and Scale Factor allow users to efficiently process and analyze the data. The full range of attributes may not be applicable to all variables. Additional information on variable attributes is typically available in the data, user guide, and/or other product documentation.

For questions on a specific variable, please use the Earthdata Forum.

Name Description Units Data Type Fill Value Valid Range Scale Factor
ACCA_State Automatic Cloud Cover Assessment Algorithm (ACCA) Classification Class uint8 255 0 to 1 N/A
Band1_SRF_REF Band 1 Surface Reflectance N/A int16 -32768 -2000 to 16000 0.0001
Band2_SRF_REF Band 2 Surface Reflectance N/A int16 -32768 -2000 to 16000 0.0001
Band3_SRF_REF Band 3 Surface Reflectance N/A int16 -32768 -2000 to 16000 0.0001
Band4_SRF_REF Band 4 Surface Reflectance N/A int16 -32768 -2000 to 16000 0.0001
Band5_SRF_REF Band 5 Surface Reflectance N/A int16 -32768 -2000 to 16000 0.0001
Band7_SRF_REF Band 7 Surface Reflectance N/A int16 -32768 -2000 to 16000 0.0001
Band61_TOA_BT Band 6 Top of Atmosphere and Brightness Temperature resampled to 30 m; low gain °C int16 -32768 -32767 to 32767 0.01
Band62_TOA_BT Band 6 Top of Atmosphere and Brightness Temperature resampled to 30 m; high gain °C int16 -32768 -32767 to 32767 0.01
Composite_Path Internal compositing algorithm pathway code N/A uint8 N/A 0 to 15 N/A
Day_Of_Year Day of year the selected Landsat pixel was acquired Day int16 0 1 to 366 N/A
DT_Cloud_State Decision Tree Cloud Classification Class uint8 255 0 to 200 N/A
L1T_Column Pixel column number in the input Level 1T image N/A uint16 65535 0 to 10000 N/A
L1T_Index Index to the L1T image that the pixel was selected from N/A uint16 65535 0 to 65534 N/A
L1T_Row Pixel row number in the input Level 1T image N/A uint16 65535 0 to 10000 N/A
NBAR_Solar_Zenith Solar zenith used for NBAR generation of pixel surface reflectance value Degree int16 -32768 0 to 9000 0.01
NDVI_SRF Normalized Difference Vegetation Index (NDVI) value N/A int16 -32768 -10000 to 10000 0.0001
Num_Of_Obs Number of observations considered over the composition period Number uint16 N/A 0 to 65534 N/A
Saturation_Flag The least significant bit to the most significant bit corresponds to bands 1, 2, 3, 4, 5, 61, 62, 7; with a bit set to 1 signifying saturation in that band and 0 not saturated Bit Field uint8 N/A 0 to 255 N/A
Sensor Landsat satellite that the pixel was selected from (4=Landsat 4 TM, 5=Landsat 5 TM, 7 = Landsat 7 ETM+) N/A uint8 255 0 to 254 N/A
Sensor_Azimuth Sensor azimuth Degree int16 -32768 -18000 to 18000 0.01
Sensor_Zenith Sensor zenith (nadir = 0 degrees) Degree int16 -32768 0 to 9000 0.01
Solar_Azimuth Solar azimuth Degree int16 -32768 -18000 to 18000 0.01
Solar_Zenith Solar zenith of pixel observation (directly overhead = 0 degrees) Degree int16 -32768 0 to 9000 0.01
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