N: 90 S: -90 E: 180 W: -180
Description
The Cloud Mask identifies whether pixels are cloud-covered or not. This is important because algorithms to determine cloud properties should only run on cloudy pixels, and other algorithms that require clear-sky pixels need to screen clouds out. In practice, users apply cloud_flag for strict cloud removal and cloud_flag_dilated when they want a conservative mask that reduces cloud-edge artifacts in downstream products (e.g., Rrs, chlorophyll). The CLDMASK is used operationally as the “cloud and cloud-adjacent” screen.
Core geophysical variables in this suite include:
• cloud_flag — Cloud mask (bitmask; identifies cloud-contaminated pixels)
• cloud_flag_dilated — Cloud or cloud-adjacent pixel mask (bitmask; includes surrounding pixels)
• l2_flags — Level-2 Processing Flags (bitmask)
Product Summary
Documents
ALGORITHM THEORETICAL BASIS DOCUMENT (ATBD)
GENERAL DOCUMENTATION
Variables
The table below lists the variables contained within a single granule for this dataset. Variables often contain observed or derived geophysical measurements collected from a variety of sources, including remote sensing instruments on satellite and airborne platforms, field campaigns, in situ measurements, and model outputs. The terms variable, parameter, scientific data set, layer, and band have been used across NASA’s Earth science disciplines; however, variable is the designated nomenclature in NASA’s Common Metadata Repository (CMR). Variable metadata attributes such as Name, Description, Units, Data Type, Fill Value, Valid Range, and Scale Factor allow users to efficiently process and analyze the data. The full range of attributes may not be applicable to all variables. Additional information on variable attributes is typically available in the data, user guide, and/or other product documentation.
For questions on a specific variable, please use the Earthdata Forum.
| Name Sort descending | Description | Units | Data Type | Fill Value | Valid Range | Scale Factor | Offset |
|---|---|---|---|---|---|---|---|
| geophysical_data/cloud_flag | Cloud mask | Dimensionless | int8 | -128 | 0 to 127 | N/A | N/A |
| geophysical_data/cloud_flag_dilated | Cloud or cloud-adjacent pixel mask | Dimensionless | int8 | -128 | 0 to 127 | N/A | N/A |
| geophysical_data/l2_flags | geophysical_data/l2_flags | dimensionless | int32 | -32767 | N/A | N/A | N/A |
| navigation_data/latitude | Latitude | degrees_north | float32 | -32767 | -90 to 90 | N/A | N/A |
| navigation_data/longitude | Longitude | degrees_east | float32 | -32767 | -180 to 180 | N/A | N/A |
| scan_line_attributes/clat | Cnetral Latitude | degrees_north | float32 | -32767 | -90 to 90 | N/A | N/A |
| scan_line_attributes/clon | Central Longitude | degrees_east | float32 | -32767 | -180 to 180 | N/A | N/A |
| scan_line_attributes/day | Scan day | days | int32 | -32767 | 0 to 366 | N/A | N/A |
| scan_line_attributes/elat | Ending Latitude | degrees_north | float32 | -32767 | -90 to 90 | N/A | N/A |
| scan_line_attributes/elon | Ending Longitude | degrees_east | float32 | -32767 | -180 to 180 | N/A | N/A |
| scan_line_attributes/msec | Scan time, milliseconds of day | milliseconds | int32 | -32767 | 0 to 86400000 | N/A | N/A |
| scan_line_attributes/scantime | Scan Unix time | N/A | float64 | -32767 | 0 to 10000000000 | N/A | N/A |
| scan_line_attributes/slat | Starting Latitude | degrees_north | float32 | -32767 | -90 to 90 | N/A | N/A |
| scan_line_attributes/slon | Starting Longitude | degrees_east | float32 | -32767 | -180 to 180 | N/A | N/A |
| scan_line_attributes/year | Scan year | years | int32 | -32767 | 1900 to 2100 | N/A | N/A |
| sensor_band_parameters/FoBar | Mean Solar Flux | N/A | float32 | -32767 | 0 to 250 | N/A | N/A |
| sensor_band_parameters/Tau_r | Rayleigh Optical Thickness | dimensionless | float32 | -32767 | 0 to 0.5 | N/A | N/A |
| sensor_band_parameters/wavelength | wavelengths | nm | float32 | -32767 | 0 to 20000 | N/A | N/A |