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ICDC
CENIntegrated Climate Data Center ICDC

Photo: getty images/L. Calvetti

Land Surface Albedo from MODIS

MODIS land surface white sky broadband albedo, Feb 2000
MODIS global land surface white sky broadband albedo, Feb 2000. Copyright: UHH/CEN/AJB

Topics

Access

UNRESTRICTED:

RESTRICTED: This link to the data set is only available for a restricted user group.  The data set is only accessible in CEN/MPI net or accessible from external nets with a customer account.  Please contact ICDC if you would like to access this data from outside the network.

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Description

This data set comprises daily values of the gridded global land surface albedo derived from MODIS reflectance values observed at bands 1-7 for periods of 16 days. Depending on the availability data from EOS-TERRA and (after July 2002) EOS-AQUA are used.

We are offering the data set with a spatial resolution of 0.05° (about 5600 m). This is the first albedo data set of MODIS Collection 6.1.

Note that the data set has been modified by us at ICDC. The landmask of the original data set was incomplete. It showed land surface albedo values over sea area like, e.g., the North Sea. The modified data set, which is offered here, contains information about the land-water distribution given in the MODIS land cover type data set (at ICDC) to correct this bug.

We recommend the EOS-Data hand book for further reading (see references).

Last update of data set at ICDC: July 18, 2024.

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Parameters

Parameters of the land albedo data set
NameUnit
bihemispheric broadband shortwave (0.3 … 4.0µm) surface albedo (white sky albedo) -
bihemispheric broadband shortwave surface albedo (white sky albedo) -
bihemispheric broadband near-infrared surface albedo (white sky albedo) -
bihemispheric broadband shortwave (0.3 … 4.0µm) surface albedo (black sky albedo) -
bihemispheric broadband shortwave surface albedo (black sky albedo) -
bihemispheric broadband near-infrared surface albedo (black sky albedo) -
global quality flag (0: best quality, 100% full inversions ... 5: at least 50% fill values) -
Local solar noon degree
Percent fraction of grid cell covered with valid data %
Percent snow cover fraction %
BRDF albedo retrieval uncertainty -

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Coverage, spatial and temporal resolution

Period and temporal resolution:

  • 2000-03-01 until 2024-05-31
  • Daily 16-day-composite, valid for the 1st day of the 2nd 8-day period

Coverage and spatial resolution:

  • Global
  • Spatial resolution: 0.05° x 0.05° (about 5600 m, Climate Modeling Grid)
  • Geographical longitude: 179.975°W to 179.975°E
  • Geographical latitude: 89.975°S to 89.975°N
  • Dimension: 3600 rows x 7200 columns
  • Altitude: Following topography

Format:

  • NetCDF

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Data quality

Missing days: June 24./25. 2001.

The data offered here are in netCDF format. These include, in addition to the white sky albedo (reflection of diffuse radiation) its difference to the black sky albedo (reflection of direct radiation), a quality flag giving information about the quality of the inversion, the local solar noon, the percentage snow cover fraction, the BRDF-albedo retrieval uncertainty and the percentage number of valid, high-resolution data per grid cell.

For better understanding: white sky albedo --> isotropic incident radiation from all directions assuming no direct sunlight; black sky albedo --> direct radiation from only a given solar geometry.

Original data are available in HDF-EOS Format. These data include in addition the reflectance values for each channel, the white & black sky albedo calculated separately for the visible and near infrared part of the spectrum.

This data set, based on MODIS collection 6.1 data, features a number of improvements:

  • Input reflectances are calibrated better and have improved long-term consistency
  • More input data in high geographic latitudes
  • In case of a snow cover the snow cover of the actual day is used (instead of before from the entire 16-day period)

Attention! The original data set has been modified by us (ICDC). The land mask of the original data set was incomplete, i.e. showed land surface albedo values over open water areas, e.g. the North Sea. We have corrected this bug by including the land-water distribution provided on the same grid in the MODIS land cover type data set.

For more information please refer to the references.

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Contact

LP DAAC User Services
U.S. Geological Survey (USGS)
Center for Earth Resources Observation and Science (EROS)
email: LPDAAC (at) eos.nasa.gov

Stefan Kern
University of Hamburg
email: stefan.kern (at) uni-hamburg.de

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References

Literature:

Websites:

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Data citation

Please cite the data as follows:

Schaaf, C., Wang, Z. (2024). MODIS/Terra+Aqua BRDF/Albedo Albedo Daily L3 Global 0.05Deg CMG V061 [Data set]. NASA EOSDIS Land Processes DAAC. https://doi.org/10.5067/MODIS/MCD43C3.061 , last access: July 5, 2024.

and with the following acknowledgments:

These data were provided in netCDF file format by the Integrated Climate Data Center (ICDC), University of Hamburg, Hamburg, Germany.

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