MOD09CMG v006

MODIS/Terra Surface Reflectance Daily L3 Global 0.05 Deg CMG


PI: Eric Vermote

Description

The MOD09CMG Version 6 product provides an estimate of the surface spectral reflectance of Terra Moderate Resolution Imaging Spectroradiometer (MODIS) Bands 1 through 7, resampled to 5600 meter (m) pixel resolution and corrected for atmospheric conditions such as gasses, aerosols, and Rayleigh scattering. The MOD09CMG data product provides 25 layers including MODIS bands 1 through 7; Brightness Temperature data from thermal bands 20, 21, 31, and 32; along with Quality Assurance (QA) and observation bands. This product is based on a Climate Modeling Grid (CMG) for use in climate simulation models.

Characteristics

Improvements/Changes from Previous Versions

  • Improvements to the aerosol retrieval and correction algorithm along with new aerosol retrieval look-up tables.
  • Refinements to the internal snow, cloud, and cloud shadow detection algorithms. Uses Bidirectional Reflectance Distribution Function (BRDF) database to better constrain the different threshold used.
  • Processes ocean bands to create a new Surface Reflectance Ocean product and provides QA datasets for these bands.
  • Improved discrimination of salt pans from cloud and snow, along with the inclusion of a salt pan flag in the QA band.

Product Maturity

Validation at stage 3 has been achieved for all MODIS surface reflectance products. Further details regarding MODIS land product validation for the MOD0CMG data product is available from the MODIS land team validation site.

Collection and Granule

Collection

Characteristic Description
CollectionTerra MODIS
DOI10.5067/MODIS/MOD09CMG.006
File Size515 MB
Temporal ResolutionDaily
Temporal Extent2000-02-24 to Present
Spatial ExtentGlobal
Coordinate SystemGeographic Latitude and Longitude
DatumN/A
File FormatHDF
Geographic DimensionsGlobal

Granule

Characteristic Description
Number of Science Dataset (SDS) Layers25
Columns/Rows7200 x 3600
Pixel Size5600 m

Layers

SDS Name Description Units Data Type Fill Value No Data Value Valid Range Scale Factor Additional Offset
Coarse Resolution Surface Reflectance Band 1 Surface Reflectance Band 1 (620-670 nm) N/A 16-bit signed integer -28672 N/A -100 to 16000 0.0001 N/A
Coarse Resolution Surface Reflectance Band 2 Surface Reflectance Band 2 (841-876 nm) N/A 16-bit signed integer -28672 N/A -100 to 16000 0.0001 N/A
Coarse Resolution Surface Reflectance Band 3 Surface Reflectance Band 3 (459-479 nm) N/A 16-bit signed integer -28672 N/A -100 to 16000 0.0001 N/A
Coarse Resolution Surface Reflectance Band 4 Surface Reflectance Band 4 (545-565 nm) N/A 16-bit signed integer -28672 N/A -100 to 16000 0.0001 N/A
Coarse Resolution Surface Reflectance Band 5 Surface Reflectance Band 5 (1230-1250 nm) N/A 16-bit signed integer -28672 N/A -100 to 16000 0.0001 N/A
Coarse Resolution Surface Reflectance Band 6 Surface Reflectance Band 6 (1628-1652 nm) N/A 16-bit signed integer -28672 N/A -100 to 16000 0.0001 N/A
Coarse Resolution Surface Reflectance Band 7 Surface Reflectance Band 7 (2105-2155 nm) N/A 16-bit signed integer -28672 N/A -100 to 16000 0.0001 N/A
Coarse Resolution Solar Zenith Angle Solar Zenith Angle Degree 16-bit signed integer 0 N/A 1 to 18000 0.01 N/A
Coarse Resolution View Zenith Angle View Zenith Angle Degree 16-bit signed integer 0 N/A 1 to 18000 0.01 N/A
Coarse Resolution Relative Azimuth Angle Relative Azimuth Angle Degree 16-bit signed integer 0 N/A -18000 to 18000 0.01 N/A
Coarse Resolution Ozone Ozone Resolution cm atm 8-bit unsigned integer 0 N/A 1 to 255 0.0025 N/A
Coarse Resolution Brightness Temperature Band 20 Band 20 Brightness Temperature (3.360-3.840 μm) Kelvin 16-bit unsigned integer 0 N/A 1 to 40000 0.01 N/A
Coarse Resolution Brightness Temperature Band 21 Band 21Brightness Temperature (3.929-3.989 μm) Kelvin 16-bit unsigned integer 0 N/A 1 to 40000 0.01 N/A
Coarse Resolution Brightness Temperature Band 31 Band 31 Brightness Temperature (10.780-11.280 μm) Kelvin 16-bit unsigned integer 0 N/A 1 to 40000 0.01 N/A
Coarse Resolution Brightness Temperature Band 32 Band 32 Brightness Temperature (11.770-12.270 μm) Kelvin 16-bit unsigned integer 0 N/A 1 to 40000 0.01 N/A
Coarse Resolution Granule Time Granule time of day Hours 16-bit signed integer 0 N/A 1 to 2355 N/A N/A
Coarse Resolution Band 3 Path Radiance Band 3 Radiance N/A 16-bit signed integer -28672 N/A -100 to 16000 0.0001 N/A
Coarse Resolution QA Quality Assurance Bit Field 32-bit unsigned integer 0 N/A 1 to 1073741824 N/A N/A
Coarse Resolution Internal CM Internal Cloud Mask Bit Field 16-bit unsigned integer 0 N/A 1 to 8191 N/A N/A
Coarse Resolution State QA State Quality Assurance Bit Field 16-bit unsigned integer 0 N/A 1 to 65535 N/A N/A
Coarse Resolution Number Mapping Number Mapping Cloud/Snow Bit Field 32-bit unsigned integer 0 N/A 1 to 2097151 N/A N/A
number of 500m pixels averaged b3-7 Number of 500m pixels used in average N/A 16-bit unsigned integer 0 N/A 1 to 200 N/A N/A
number of 500m rej. detector Number of 500m pixels rejected for use N/A 8-bit unsigned integer 0 N/A 1 to 100 N/A N/A
number of 250m pixels averaged b1-2 Number of 250m pixels used in b1-2 average N/A 16-bit unsigned integer 0 N/A 1 to 640 N/A N/A
n pixels averaged Number of pixels used in average N/A 8-bit unsigned integer 0 N/A 1 to 40 N/A N/A

Product Quality

The Coarse Resolution QA, Internal CM, State QA, and Number Mapping layers are stored in an efficient bit-encoded manner. The unpack_sds_bits executable from the LDOPE Tools is available to the user community to help parse and interpret these layers.

The bit flags for the Coarse Resolution QA, Internal CM, State QA, and Number Mapping layers are provided in the User Guide in Tables 10, 13, 14, and 15.

Known Issues

Striping due to a dead detector is noticeable for bands 5, 6, and 7 in scenes acquired February 24 through October 31, 2000. Corrections were implemented to reduce the striping in data acquired after November 1, 2000. Users should always check the band quality for dead detectors even though reflectance values may be in the valid range. For complete information about the MOD09CMG known issues please refer to the MODIS Land Quality Assessment website.

Documentation

Using the Data

E-Learning

Getting Started with MODIS V6 Surface Reflectance Data Part 3: Interpreting Quality Information

Data In Action

There's a Hurricane A-comin': Observing the 2017 Atlantic Hurricane Season with Satellite Imagery

Tools

Citation

DOI: 10.5067/MODIS/MOD09CMG.006

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