AVW quantifies the spectral center of water-leaving reflectance in nanometers, indicating water type from clear blue to productive green/brown waters. This Level-4 mapped product from the NOAA-21 VIIRS satellite is produced by OB_CLOUD for oceanographic applications. The dataset is version 2025.0, indicating a recent processing standard.
Use Cases
- Classify water types (e.g., oligotrophic vs. productive) based on the avw value in nanometers.
- Guide chlorophyll-a (chlor_a) retrieval algorithm selection by using avw as a spectral shape index.
- Detect regional changes in coastal water optical properties by analyzing spatial patterns in the avw geophysical variable.
- Provide context for other ocean color products like Kd_490 or PAR by correlating with the apparent visible wavelength.
Strengths
- Provides a single, summary geophysical variable (avw) derived from the full visible reflectance spectrum.
- Includes quality flags for cloud, glint, and aerosol conditions to guide data filtering.
Limitations
- Interpretation of the avw metric can be ambiguous in optically complex coastal and inland waters.
- Specific data volume, spatial resolution, and temporal coverage details are not provided in the input.
Provenance
- Source
- NOAA-21 VIIRS satellite sensor, processed by OB_CLOUD.
- Collection Method
- Derived from Level-2 water-leaving reflectance (Rrs) spectra to create a Level-4 globally mapped product.
- Time Range
- null
- Freshness
- null
- Geography
- Global ocean coverage.