| Import MODIS | |
The version 2.3 of the BEAM software supports a subset of the products available of the NASA sensor MODIS, both on the Aqua and Terra platform. These products can be imported into VISAT, used as input products in the scientific data processors (where applicable) and accessed by Java developers using the Java product I/O framework.
Due to the size of the MODIS products, especially in 250 m resolution, it is strongly recommended to work with these products using a spatial subset.
The following MODIS data product types are supported by BEAM:
| Product Type | Content | Description |
|---|---|---|
MOD021KMMYD021KM |
MODIS/Terra/Aqua Calibrated Radiances 5-Min L1B Swath 1 km | This Level 1B product contains calibrated and geolocated radiances at-aperture for all 36 MODIS spectral bands at 1km resolution. |
MOD02HKMMYD02HKM |
MODIS/Terra/Aqua Calibrated Radiances 5-Min L1B Swath 500 m | This Level 1B product contains calibrated and geolocated radiances at-aperture for MODIS spectral bands 1 through 7 at 500m resolution. |
MOD02QKMMYD02QKM |
MODIS/Terra/Aqua Calibrated Radiances 5-Min L1B Swath 250 m | This Level 1B product contains calibrated and geolocated radiances at-aperture for MODIS spectral bands 1 and 2 at 250m resolution. |
MODOCL2MYDOCL2 |
MODIS/Terra/Aqua Ocean Color Radiance Products 5-Min L2 Swath 1 km Day | The MODIS Level 2 ocean color water leaving radiance product, MxDOCL2, contains normalized water-leaving radiance for 7 of the 36 wavelengths/spectral bands (Band 8 through 14, 412 through 618nm) of MODIS which are used to derive nearly all the ocean products, ocean aerosol properties and clear water epsilons (parameters numbers 1-12). This Level 2 data collection has daily coverage with a 1-km resolution at nadir. |
MODOCL2AMYDOCL2A |
MODIS/Terra/Aqua Ocean Color Derived Products Group 1 5-Min L2 Swath 1 km Day | This MODIS Level 2 Ocean Color Derived Products Group 1, MxDOCL2A, product contains the following ocean products: chlorophyll derived from several different algorithms, phycobilin pigment concentrations, chlorophyll fluorescence, suspended solids concentration, coccolith, calcite, coccolith corrected pigment concentration and ocean water attenuation (ocean parameter number 13-25). This Level 2 product has daily coverage with a l-km resolution at nadir. |
MODOCL2BMYDOCL2B |
MODIS/Terra/Aqua Ocean Color Derived Products Group 2 5-Min L2 Swath 1 km Day | This MODIS Level 2 Ocean Color Derived Products Group 2, MxDOCL2B, product contains the following ocean products: chlorophyll_a pigment concentration for Case 2 waters using 2 and 3 band algorithms, photosynthetic available radiation (PAR) and absorbed radiation by phytoplankton (ARP), organic matter concentration, total absorption at 5 wavebands, chlorophyll and gelbstoff absorption coefficients. (ocean parameter number 26-36). This Level 2 product has daily coverage with a 1-km resolution at nadir. |
MOD28L2MYD28L2 |
MODIS/Terra/Aqua Sea Surface Temperature Products 5-Min L2 Swath 1 km | This MODIS Level 2 Sea Surface Temperature Product,MxD28L2, product provides a long wavelength (11-12um, SST) sea surface temperature and a short wavelength sea surface temperature (3-4um, SST4) at 1-km resolution over the global oceans. Day and night retrievals are provided as separate products for both SST and SST4. |
Due to the operational mode of the MODIS sensor, all MODIS products available from NASA experience "overlapping" scan lines. This is the so called "bow-tie" effect. These artifacts will be automatically removed by map-projecting the MODIS products.
Since BEAM 3.5 this issue is solved by a special geo-coding. So these artifacts do not occure any more even in not map-projected MODIS products.
The supported MODIS Level 2 products do not contain geo-location information. Instead, this
information is stored in an accompagnying quality control file (MxDOCQC). The BEAM software tries
to locate this file in the same directory as the Level 2 product resides. If the geo-location file is not
present, the Level 2 product will be opened as raw datasets without geo-coding.
The current version of BEAM does not support flag coding of MODIS products and therefore bitmask overlays are currently not possible.