No description available.

The MODIS MCD43A4 Version 6 Nadir Bidirectional reflectance distribution function Adjusted Reflectance (NBAR) data set is a daily 16-day product. The Julian date in the granule ID of each specific file represents the 9th day of the 16 day retrieval period, and consequently the observations are weighted to estimate the Albedo for that day. The MCD43A4 algorithm, as is with all combined products, has the luxury of choosing the best representative pixel from a pool that includes all the acquisitions from both the Terra and Aqua sensors from the retrieval period.

The MODIS MCD43A2 Version 6 Bidirectional reflectance distribution function and Albedo (BRDF/Albedo) Quality data set is a 500 meter daily 16-day product that contains all the quality information for the corresponding 16-day MCD43A3 Albedo and the MCD43A4 Nadir-BRDF (NBAR) products. The Julian date in the granule ID of each specific file represents the 9th day of the 16 day retrieval period.

The MODerate-resolution Imaging Spectroradiometer (MODIS) BRDF/Albedo Model Parameters product (MCD43A1) contains three-dimensional (3D) data sets providing users with weighting parameters for models used to derive the Albedo and BRDF products (MCD43A3 and MCD43A4). The models support the spatial relationship and parameter characterization describing the differences in radiation due to the scattering (anisotropy) of each pixel, relying on multi-date, atmospherically corrected, cloud-cleared input data measured over 16-day periods.

The Moderate Resolution Imaging Spectroradiometer (MODIS) MCD43A4 Version 6.1 Nadir Bidirectional Reflectance Distribution Function (BRDF)-Adjusted Reflectance (NBAR) dataset is produced daily using 16 days of Terra and Aqua MODIS data at 500 meter (m) resolution. The view angle effects are removed from the directional reflectances, resulting in a stable and consistent NBAR product. Data are temporally weighted to the ninth day which is reflected in the Julian date in the file name.Users are urged to use the band specific quality flags to isolate the highest quality full inversion results for their own science applications as described in the [User Guide](https://www.umb.edu/spectralmass/modis-user-guide-v006-and-v0061/mcd43a4-nbar-product/).The MCD43A4 provides NBAR and simplified mandatory quality layers for MODIS bands 1 through 7. Essential quality information provided in the corresponding [MCD43A2](https://doi.org/10.5067/MODIS/MCD43A2.061) data file should be consulted when using this product.Known Issues* For complete information about known issues please refer to the [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=MODIS&sat=TerraAqua&as=61).Improvements/Changes from Previous Versions* The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017.* A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).

The MODerate-resolution Imaging Spectroradiometer (MODIS) BRDF/Albedo Quality product (MCD43A2) describes the overall condition of the other BRDF and Albedo products. The MCD43A2 product contains 16 days of data at 500-meter spatial resolution provided in a level-3 gridded data set in Sinusoidal projection, and includes albedo quality, snow conditions, ancillary, and inversion information.

The Moderate Resolution Imaging Spectroradiometer (MODIS) MCD43C4 Version 6.1 Bidirectional Reflectance Distribution Function and Albedo (BRDF/Albedo) Nadir BRDF-Adjusted Reflectance (NBAR) dataset is produced daily using 16 days of Terra and Aqua MODIS data in a 0.05 degree (5,600 meters at the equator) Climate Modeling Grid (CMG). Data are temporally weighted to the ninth day of the retrieval period which is reflected in the Julian date in the file name. This CMG product covers the entire globe for use in climate simulation models. MCD43C4 removes view angle effects from directional reflectances to model the values as if they were collected from a nadir view at local solar noon. These NBAR values are calculated from MCD43C1 (https://doi.org/10.5067/MODIS/MCD43C1.061). The product includes separate NBAR layers for MODIS spectral bands 1 through 7 as well as ancillary layers for quality, local solar noon, percent finer resolution inputs, snow cover, and uncertainty. Improvements/Changes from Previous Versions * The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017. * A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).

The MODIS Near Real Time (NRT) Combined Aqua and Terra Nadir BRDF-Adjusted Reflectance, MCD43A4N, Nadir Bidirectional Reflectance Distribution Function (BRDF)-Adjusted Reflectance (NBAR) dataset is produced daily using 16 days of Terra and Aqua MODIS data at 500 meter (m) resolution. This product in sinusoidal map projection that provides view angle corrected Nadir BRDF-Adjusted Reflectances (NBAR) at local solar noon for the 7 land bands, along with corresponding mandatory QA dataset.There is a significant change in the science algorithm of the Collection 61 (C61) NRT BRDF/Albedo products and, therefore significant differences/discontinuities between the C6 and C61 products. C61 algorithm changes are intended to minimize the differences between the NRT and Standard BRDF. The C61 NRT BRDF code has been modified to allow for an extra round of magnitude inversion, following a full inversion using the full set of inputs. This extra magnitude inversion will only use the set of 9 days that are overlapping between standard and NRT, with the highest weight being assigned to the last day.Additional information from MODIS Land Science Team at:https://modis-land.gsfc.nasa.gov/brdf.html

The Moderate Resolution Imaging Spectroradiometer (MODIS) MCD43A4 Version 6.1 Nadir Bidirectional Reflectance Distribution Function (BRDF)-Adjusted Reflectance (NBAR) dataset is produced daily using 16 days of Terra and Aqua MODIS data at 500 meter (m) resolution. The view angle effects are removed from the directional reflectances, resulting in a stable and consistent NBAR product. Data are temporally weighted to the ninth day which is reflected in the Julian date in the file name. The MCD43A4 provides NBAR and quality layers for MODIS bands 1 through 7. Improvements/Changes from Previous Versions * The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017. * A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).

The MODerate-resolution Imaging Spectroradiometer (MODIS) Albedo product (MCD43A3) provides 500-meter data describing both directional hemispherical reflectance (black-sky albedo) and bihemispherical reflectance (white-sky albedo). The MCD43A3 product contains 16 days of data provided in a level-3 gridded data set in Sinusoidal projection.