This image is a false-color representation of the second of four Science Data Sets in the BRDF/Albedo Quality product. Snow_BRDF_Albedo is shown for data acquired between January 17 and February 1, 2007 over the Adriatic Sea, including Italy, Croatia, Bosnia, Serbia, and Albania (h19v04).
Snow_BRDF_Albedo describes which pixels contain snow-free albedo values (green), versus those calculated in the presence of snow (yellow). Black pixels are either cloud or water bodies. Using this quality information, it is apparent that the white pixels in the Nadir BRDF-Adjusted Reflectance product are snow and not clouds.
The MODerate-resolution Imaging Spectroradiometer (MODIS) BRDF/Albedo Quality product (MCD43B2) describes the overall condition of the other BRDF and Albedo products. MCD43B2 data are 16-day composites at 1-kilometer spatial resolution provided as a level-3 gridded product in the Sinusoidal projection and include albedo quality, snow conditions, ancillary information, and inversion information.
Both Terra and Aqua data are used in the generation of this product, providing the highest probability for quality input data and designating it as an "MCD," meaning "Combined," product.
Version-5 MODIS/Terra+Aqua BRDF/Albedo products are Validated Stage 1, meaning that accuracy has been estimated using a small number of independent measurements obtained from selected locations and time periods and ground-truth/field program efforts. Although there may be later improved versions, these data are ready for use in scientific publications.
Temporal Coverage | February 24, 2000 - |
Area | ~10 x 10 lat/long |
File Size | ~0.4 MB |
Projection | Sinusoidal |
Data Format | HDF-EOS |
Dimensions | 1200 x 1200 rows/columns |
Resolution | 1 kilometer |
Science Data Sets (SDS HDF Layers) | 4 |
Science Data Sets for MODIS Terra+Aqua BRDF/Albedo Quality 16-Day L3 Global 1km SIN Grid V005 (MCD43B2):
Science Data Sets (HDF Layers) 4 |
UNITS | BIT TYPE | FILL | VALID RANGE |
BRDF_Albedo_Quality | Concatenated flags | 8-bit unsigned integer | 255 | 0–254 |
Snow_BRDF_Albedo | Concatenated flags | 8-bit unsigned integer | 255 | 0–254 |
BRDF_Albedo_Ancillary | Concatenated flags | 16-bit unsigned integer | 32767 | 0–32766 |
BRDF_Albedo_Band_Quality | Concatenated flags | 32-bit unsigned integer | 4294967295 | 0–4294967294 |
One of the more significant differences between the V004 and V005 BRDF/Albedo data products is that the quality information is no longer embedded as a Science Data Set in each product. BRDF/Albedo Quality is now generated as stand alone data in a separate product, MCD43B2, which can be applied to the other BRDF/Albedo products externally through pixel matching.
The table below lists the four Science Data Sets represented in the Quality product, with their associated QC bit legends.
The 1 kilometer BRDF/Albedo products are averages of the 500 meter values found in the MCD43A products. Thus snow free and snow covered 500-m pixels are averaged together and if any of the 500-m pixels were snow-covered the 1km is flagged as snowy.
*NOTE: The first two Quality SDSs (BRDF_Albedo_Quality and Snow_BRDF_Albedo) are not bit packed. They are complete byte words that can be read directly.
Byte Word | BRDF_Albedo_Quality* |
1 | Processed, see other QA (magnitude BRDF inversions) |
0 | Processed, good quality (full BRDF inversion) |
255 | Fill Value |
Byte Word | Snow_BRDF_Albedo* |
1 | Snow albedo retrieved |
0 | Snow-free albedo retrieved |
255 | Fill Value |
Bit Comb. | BRDF_Albedo_Ancillary |
00–03 | Platform |
0 | Terra |
1 | Terra/Aqua |
2 | Aqua |
04–07 | Land/Water |
0 | Shallow ocean |
1 | Land (Nothing else but land) |
2 | Ocean and lake shorelines |
3 | Shallow inland water |
4 | Ephemeral water |
5 | Deep inland water |
6 | Moderate or continental ocean |
7 | Deep ocean |
08–14 | Solar Zenith Angle at Local Solar Noon |
15 | QAFill |
255 | Fill Value |
Bit Comb. | BRDF_Albedo_Band_Quality |
00–03 | Band 1 Quality |
0 | best quality, 75% or more with best full inversions |
1 | good quality, 75% or more with full inversions |
2 | Mixed, 50% or less full inversions and 25% or less fill values |
3 | All magnitude inversions or 50% or less fill values |
4 | 75% or more fill values |
04–07 | Band 2 Quality (see explanation for band 1) |
08–11 | Band 3 Quality (see explanation for band 1) |
12–15 | Band 4 Quality (see explanation for band 1) |
16–19 | Band 5 Quality (see explanation for band 1) |
20–23 | Band 6 Quality (see explanation for band 1) |
24–27 | Band 7 Quality (see explanation for band 1) |
28–30 | TBD |
31 | QAFill |
255 | Fill Value |
Please find the current MODIS-related Data Redistribution and Pricing policies on the MODIS Policies Section of this Web Site
LP DAAC Acknowledgement and Citations Policy
In the event that data distributed from the Land Processes DAAC are incorporated into your research, please supply the following acknowledgment within your published work: "These data are distributed by the Land Processes Distributed Active Archive Center (LP DAAC), located at the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center (lpdaac.usgs.gov)." If possible, please e-mail or send us reprints/citations of papers or oral presentations based on data obtained from the LP DAAC (see below for mailing address and e-mail address). This will help us to stay informed of how the data are being utilized.
LP DAAC User Services
U.S. Geological Survey (USGS)
Earth Resources Observation and Science (EROS) Center
47914 252nd Street
Sioux Falls, SD 57198-0001
The complete data record for this product is available through the WIST search and order interface. A near-complete record is available on-line through the Data Pool.
Please find links to (and information about) these data access tools on the Get Data Section of this Web Site.
U.S. Geological Survey (USGS)
Center for Earth Resources Observation and Science (EROS)
47914 252nd Street
Sioux Falls, SD 57198-0001
Phone Number: | 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 |