Import MODIS

Import MODIS Product

BEAM Implementation of the MODIS Product Reader

BEAM 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.

Supported MODIS Data Products

The following MODIS data product types are supported by BEAM:

Product TypeContentDescription
MOD021KM
MYD021KM
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.
MOD02HKM
MYD02HKM
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.
MOD02QKM
MYD02QKM
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.
MODOCL2
MYDOCL2
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.
MODOCL2A
MYDOCL2A
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.
MODOCL2B
MYDOCL2B
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.
MOD28L2
MYD28L2
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.

Geolocation of MODIS Products

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.

MODIS Level 2 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.

MODIS Quality Flags

The current version of BEAM does not support flag coding of MODIS products and therefore bitmask overlays are currently not possible.