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| EDG Data Set Name | Granule Shortname |
|---|---|
| MODIS/Terra BRDF/Albedo Model-1 16-Day L3 Global 1km SIN Grid | MOD43B1 |
| Version | Acquisition Range | Science Quality Status |
|---|---|---|
| V003 | August 29, 2002 (2002241) - October 7, 2002 (2002280) | Provisional as of Nov 1, 2000 |
| V004 | February 18, 2000 (2000049) | Validated Stage 1 as of February 18, 2000 |
Data Set Characteristics
Area = ~10° X 10° latitude/longitude
Image Dimensions = 4 (1200 x 1200 X 10 X 3 row/column/band/parameter)
Average File Size = 107 MB
Resolution = 1 kilometer
Projection = Sinusoidal
Data Format = HDF-EOS
Science Data Sets (SDSs) = 4
Product Description
The MODerate-resolution Imaging Spectroradiometer (MODIS) Bidirectional Reflectance Distribution Function (BRDF)/Albedo products describe how land surfaces appear under perfect scattering conditions without the influence of view angle. Every 16 days, the BRDF/Albedo algorithm relies on multidate, atmospherically corrected, cloud-cleared data and a semiempirical kernel-driven bidirectional reflectance model to determine a global set of parameters describing the BRDF of the land surface. These one kilometer gridded parameters are then used to determine directional hemispherical reflectance ("black-sky albedo"), bihemispherical reflectance ("white-sky albedo"), and nadir BRDF-adjusted reflectance (NBAR) for seven spectral bands and (in the case of albedo) three broad bands. By providing model parameters and extensive quality information, the MODIS BRDF/Albedo products offer the global remote sensing and modeling community the additional flexibility to derive reflectance and albedo measures particularly suited to their specific applications. BRDF/Albedo products are provided globally as discrete 1200 by 1200 element tiles in a Sinusoidal Grid projection (MOD43Bs) and on 0.05 degree Climate Model Grids (MOD43Cs), both in HDF-EOS format.
The MODIS/Terra BRDF/Albedo Model Parameters 16-Day L3 Global 1km SIN Grid product, MOD43B1, contains four-dimensional data sets of the parameters used in the BRDF/Albedo models: x, y, and parameter values are stored for each wavelength band of data. This 4D combination provides users with spatial orientation as well as the weighting parameters associated with the models best describing the differences in radiation due to scattering (anisotropy) in each pixel. These parameters can be used in a forward version of the model to fully reconstruct the surface BRDF and thus correct directional reflectances to a common view geometry or to compute the integrated black-sky (at any desired solar zenith angle) and white-sky albedos (as is done for MOD43B3). Alternately, the parameters can be used directly with a simple polynomial to easily estimate the black-sky albedo with good accuracy for any desired solar zenith angle. The data are stored band interleaved by pixel (BIP) and extensive quality information is provided in a bit-packed format.
The MOD43B1 image shown is a representation of part of the BRDF_Albedo_Parameters layer in the product, displaying only the isotropic weighting parameter for red Band 1 over the Great Lakes between Canada and the United States (Tile h11v04) in July 2005. The values in this image correspond to the coefficient used per pixel for the isotropic variable in the BRDF/Albedo model equation. Black indicates pixels that were not qualified as input to the model, due primarily to water or cloud content. The colored pixels in this particular tile range in value from 0-100 (red - violet), and indicate varying levels of correction for view angle.
NOTE: These products are validated, meaning that product uncertainties are well defined over a range of representative conditions. Although there may be later improved versions, these data are ready for use in scientific publications.
| SDS | Units | Data Type-bit | Fill Value | Valid Range | Multiply by Scale Factor |
Additional Offset | Dimensions |
|---|---|---|---|---|---|---|---|
| BRDF Albedo Parameters | Reflectance | 16-bit signed integer | 32767 | 0 - 32766 | 0.001 | na | 1D X-Dim 2D Y-Dim 3D#Land Bands+3 4D #Parameters |
| BRDF Shape Indicators | Ratio or coefficient | 8-bit unsigned integer | 255 | 0 - 254 | 0.040 | 25.0 | 1D X-Dim 2D Y-Dim 3D # Shape Fields |
| *BRDF Quality | Concatenated flags | 32-bit unsigned integer | 4294967295 | 0 - 4294967295 | na | na | 1D X-Dim 2D Y-Dim 3D # QC Words |
| BRDF Type | Model or Type number | 8-bit unsigned integer | 255 | 0 - 254 | na | na | 1D X-Dim 2D Y-Dim 3D # Type Fields |
*MODIS BRDF/Albedo QA Science Data Sets
View a Version Formatted for Printing
Retrieve the MOD43B1v4 MODIS product through the LP DAAC Data Pool
Via Search Tool: http://e4eil01u.ecs.nasa.gov:22000/WebAccess/drill?attrib=esdt&esdt=MOD43B1.4&group=MOLT
Via FTP Directory: ftp://e4ftl01u.ecs.nasa.gov/MOLT/MOD43B1.004/
Order These Data through the EOS Data Gateway
MODIS/TERRA BRDF/ALBEDO MODEL-1 16-DAY L3 GLOBAL 1KM SIN GRID V004
EOS Data Gateway Search Tips
| Data Center: | LPDAAC |
|---|---|
| Sensor: | MODIS |
| Dataset: | MODIS/Terra BRDF/Albedo Model-1 16-Day L3 Global 1km SIN Grid |
| Spatial: | HORIZONTALTILENUMBER Max/Min VERTICALTILENUMBER Max/Min |
| Geographic Extent: | Type Lat/Long Range or Draw on Map |
| Temporal Extent: | 2000-02-18 to present |
Product Information
Contact Information
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LP DAAC User Services U.S. Geological Survey (USGS) Earth Resources Observation and Science Center (EROS) 47914 252nd Street Sioux Falls, SD 57198-0001 |
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|---|---|
| Phone: | 605-594-6116 |
| Toll Free: | 866-573-3222 |
| 866-LPE-DAAC | |
| Fax: | 605-594-6963 |
| Email: | LPDAAC@eos.nasa.gov |
| Web: | http://LPDAAC.usgs.gov |
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