## NASA Level-2 Product Reader

### Ocean Level-2 Data Products

The L2 data product reader supports data from a number of missions, processed via the NASA l2gen processing code.

- CZCS
- GOCI
- HawkEye
- HICO
- MERIS
- MODIS
- MOS
- OCM
- OCTS
- OSMI
- PACE
- SeaWiFS
- VIIRS

Each Level-2 product is generated from a corresponding Level-1A product.The main data contents of the product are the geophysical values for each pixel,derived from the Level-1A raw radiance counts by applying the sensor calibration, atmospheric corrections, and bio-optical algorithms. Each Level-2 product corresponds exactly in geographical coverage (scan-line and pixel extent) to that of its parent Level-1A product and is stored in one physical HDFfile. The standard Ocean Color product contains 12 geophysical values derived for each pixel: six water-leaving radiances for bands 1 to 6, the chlorophyll a concentration, the diffuse attenuation coefficient at band 3, the epsilon value for the aerosol correction of bands 7 and 8, the angstrom coefficient for bands 4 and 8, and the aerosol optical thickness at band 8. The standard SST product contains 11-micron and 4-micron (nighttime only) SST for each pixel. In addition, 32 flags are associated with each pixel indicating if any algorithm failures or warning conditions occurred for that pixel.

This reader adds masks for each of the level2 flags. Additionally this reader orients the data such that north is at the top of the screen display and west is at the left of the screen display.

Format Specifications

- Ocean Level-2 Data Product Document
  https://oceancolor.gsfc.nasa.gov/DOCS/Ocean_Level-2_Data_Products.pdf