Aqua MODIS ocean reflectance band 10 data from the MYDOCGA product over the Iberian Peninsula, Portugal on August 19, 2018.
View full-size imageThe MYDOCGA Version 6 Level 2 Gridded Lite (L2G-lite) Ocean Reflectance product provides an estimate of the surface spectral reflectance data from Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) bands 8 through 16. Data have been corrected for atmospheric conditions such as gasses, aerosols, and Rayleigh scattering. MYDOCGA is a daily land product with a pixel size of 1 kilometer (km). The product is referred to as ocean reflectance because bands 8 through 16 are used primarily to produce ocean products. The MYDOCGA, as with other L2G data sets, stores the “best available pixel” from all the qualifying observations in the first layer and any subsequent observations are stored in either a full or compact format layer within the Hierarchical Data Format (HDF) file.
The MYDOCGA data product is categorized with the Surface Reflectance products and has therefore attained stage 3 validation. Further details regarding MODIS land product validation for the Surface Reflectance data product are available from the MODIS Land Team Validation site.
| Characteristic | Description |
|---|---|
| Collection | Aqua MODIS |
| DOI | 10.5067/MODIS/MYDOCGA.006 |
| File Size | 25.88 MB |
| Temporal Resolution | Daily |
| Temporal Extent | 2002-07-04 to 2023-02-26 |
| Spatial Extent | Global |
| Coordinate System | Sinusoidal |
| Datum | N/A |
| File Format | HDF-EOS |
| Geographic Dimensions | ~1200 km x 1200 km |
| Characteristic | Description |
|---|---|
| Number of Science Dataset (SDS) Layers | 14 |
| Columns/Rows | 1200 x 1200 |
| Pixel Size | ~1000 m |
| SDS Name | Description | Units | Data Type | Fill Value | No Data Value | Valid Range | Scale Factor |
|---|---|---|---|---|---|---|---|
| num_observations | Number of observations per pixel | N/A | 8-bit signed integer | -1 | N/A | 0 to 127 | N/A |
| sur_refl_b08_1 | Surface Reflectance Band 8 (405-420 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| sur_refl_b09_1 | Surface Reflectance Band 9 (438-448 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| sur_refl_b10_1 | Surface Reflectance Band 10 (483-493 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| sur_refl_b11_1 | Surface Reflectance Band 11 (526-536 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| sur_refl_b12_1 | Surface Reflectance Band 12 (546-556 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| sur_refl_b13_1 | Surface Reflectance Band 13 (662-672 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| sur_refl_b14_1 | Surface Reflectance Band 14 (673-683 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| sur_refl_b15_1 | Surface Reflectance Band 15 (743-753 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| sr_refl_b16_1 | Surface Reflectance Band 16 (862-877 nm) | N/A | 16-bit signed integer | -28672 | N/A | -100 to 16000 | 0.0001 |
| QC_b8_15_1km_1 | Band Quality Bands 8-15 | Bit Field | 32-bit unsigned integer | 787410671 | N/A | 0 to 4294966019 | N/A |
| QC_b16_1km_1 | Band Quality Band 16 | Bit Field | 8-bit unsigned integer | 3 | N/A | 0 to 255 | N/A |
| orbit_pnt_1 | Orbit Pointer | N/A | 8-bit signed integer | -1 | N/A | 0 to 15 | N/A |
| granule_pnt_1 | Granule Pointer | N/A | 8-bit unsigned integer | 255 | N/A | 0 to 254 | N/A |
*If the "L2GStorageFormat" metadata value is "full" additional data layers will be present with the suffix “_f”. If the "L2GStorageFormat" metadata value is "compact" the suffix will be “_c”.
The QA layer is 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 the QC layer.
Quality assurance information should be considered when determining the usability of data for a particular science application. The ArcGIS MODIS-VIIRS Python Toolbox contains tools capable of decoding quality data layers while producing thematic quality raster files for each quality attribute.
In addition to data access and transformation processes, AppEEARS also has the capability to unpack and interpret the quality layers.
The QA bit flags for the QC_b8_15_1km_1 and QC_b16_1km_1 layers are provided in the MYDOCGA File Specification.
For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.