BRDF and Albedo model parameters, quality and Nadir BRDF Adjusted Reflectance (NBAR) - MODIS, LPDAAC MCD43 mosaic, Australia coverage

BRDF and Albedo model parameters, quality and Nadir BRDF Adjusted Reflectance (NBAR) - MODIS, LPDAAC MCD43 mosaic, Australia coverage

Link to the data

Data licence and Access rights

Alternate title

BRDF-Albedo Model Parameters, BRDF-Albedo Quality, Albedo and Nadir BRDF-Adjusted Reflectance 16-Day L3 Global 500m and 1km

Abstract or Summary

The MODIS BRDF/Albedo Model Parameters product (MCD43A1,B1) contains three-dimensional (3D) data sets providing users with weighting parameters for the models used to derive the Albedo and BRDF products (MCD43A3,B3 and MCD43A4,B4). The models support the spatial relationship and parameter characterization best 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 MODIS BRDF/Albedo Quality product (MCD43A2,B2) describes the overall condition of the other BRDF and Albedo products.

The MODIS Albedo product (MCD43A3,B3) provides data describing both directional hemispherical reflectance (black-sky albedo) and bihemispherical reflectance (white-sky albedo).

The MODIS Reflectance product (MCD43A4,B4) provides reflectance data adjusted using a bidirectional reflectance distribution function (BRDF) to model the values as if they were taken from nadir view. 

(Text from https://lpdaac.usgs.gov/dataset_discovery/modis/modis_products_table/mcd43a1, .../mcd43a2, .../mcd43a3 and .../mcd43a4).

Data are derived from the MODIS Land Products that are distributed by the LPDAAC as tiles from a global sinusoidal projection. Tiles for selected products for Australia have been downloaded and then mosaiced and remapped using the Modis Reprojection Tool (MRT). The products have been split into individual bands to reduce file size and have been reformatted to ensure consistency in SDS and attribute nomenclature.

Spatial and Temporal extents

Point of contact

Credit

CSIRO Marine and Atmospheric Research is the custodian of this dataset.

This dataset has been developed by the Time Series Remote Sensing Team, CSIRO Marine and Atmospheric Research.  The original data were supplied by the Land Processes Distributed Active Archive Center (LPDAAC), located at the U.S. Geological Survey (USGS) Earth Resources Observation and Science Center (EROS) http://lpdaac.usgs.gov.

Keywords

There are three main thesauri that AusCover recommends:

1. Global Change Master Directory (http://gcmd.nasa.gov)
2. Climate and Forecast (CF) convention standard names (http://cfconventions.org/standard-names.html).
3. Fields of Research codes (http://www.abs.gov.au/ausstats/abs@.nsf/0/6BB427AB9696C225CA2574180004463E?opendocument).

Data quality

LPDAAC are responsible for the actual data quality and provide quality channels as part of most products.  These channels are processed the same as the data channels.  The mosaicing, remapping and reformatting processes do not alter either the data or the quality fields.

Quality assessment of the LPDAAC MODIS products is undertaken by the MODIS Land Data Discipline Team, http://landweb.nascom.nasa.gov.

Data set specific link(s) for MCD43 products are:

• http://landweb.nascom.nasa.gov/cgi-bin/QA_WWW/getSummary.cgi?esdt=43

Users should be aware that not all tiles for a particular mosaic necessarily become available from the LPDAAC on the same day.  It is therefore possible that the most recent mosaic for any given product will be updated over several days, each time containing progressively more actual data within the same (standard) geographic extent.

We have had some minor issues with file corruption that have been detected by users unable to un-gzip the mosaic files.  If you discover any such files, please report them to us (see contacts section).

Validation status

Quality assessment of the LPDAAC MODIS products is undertaken by the MODIS Land Data Discipline Team, http://landweb.nascom.nasa.gov.

Data set specific link(s) for MCD43 products are:

• http://landval.gsfc.nasa.gov/ProductStatus.php?ProductID=MCD43

Related products

References

Algorithm summary

The LPDAAC product pages, https://lpdaac.usgs.gov/dataset_discovery/modis/modis_products_table/mcd43a1, .../mcd43a2, .../mcd43a3, .../mcd43a4, provide links to the ATBDs and other supporting documentation.

Note that file format and structure mentioned on the LPDAAC site and supporting documents relates to the original HDF-EOS format for the sinusoidal projection tiles and global extent. Whereas the mosaic files available from this record are HDF4 format for a geographic latitude/longitude projection for Australian extent. The mask values and data types are consistent between both the tile and mosaic versions.

We refer the user to Paget and King (2008) for mosaic and reformatting details, and to the Readme text file for filename and directory structure information.

Product version history

The mosaic data set is automatically updated daily.  In practice this means that the archive is updated within a few days of new data being released on the LPDAAC data pool.  The documentation (papers and reports, and possibly this README file) will mostly reflect the state of the data set at the time of its initial release and may not be updated in synchrony with the data themselves.  As such, the files present on the server should be regarded as the definitive inventory of the data set.

Metadata history