Aqua MODIS Level-4 Global Binned Garver-Siegel-Maritorena Model (GSM) Data provides ocean-color fields derived by inverting water-leaving reflectance with a semi-analytical model. The dataset retrieves multiple optical properties simultaneously, offering a physics-based alternative to simple band-ratio chlorophyll algorithms. It is produced by OB_CLOUD and represents version 2022.0.
Use Cases
- Modeling phytoplankton biomass by analyzing the chl_gsm (chlorophyll-a concentration) column.
- Studiating dissolved organic matter by examining the adg_443_gsm (absorption by gelbstoff and detrital material) feature.
- Analyzing particulate scattering in seawater using the bbp_443_gsm (particulate backscattering) variable.
- Comparing physics-based GSM retrievals against traditional band-ratio algorithms for chlorophyll estimation.
- Mapping global distributions of ocean optical properties derived from the suite of GSM geophysical variables.
Strengths
- Derived from Aqua MODIS satellite sensor, a major source of ocean color data.
- Provides three core geophysical variables (adg_443_gsm, bbp_443_gsm, chl_gsm) per observation.
- Uses the GSM semi-analytical model to retrieve multiple properties simultaneously from reflectance spectra.
- Offers a global, binned (Level-4) product for consistent spatial analysis.
Limitations
- Specific row count, sample size, and temporal coverage are unknown.
- Data is from version 2022.0; recency relative to current date is unclear.
- Relies on satellite remote sensing, which can be affected by cloud cover and atmospheric correction errors.
Provenance
- Source
- NASA Earthdata (platform), produced by OB_CLOUD.
- Collection Method
- Derived by inverting water-leaving reflectance from the Aqua MODIS satellite using the Garver-Siegel-Maritorena (GSM) semi-analytical model.
- Time Range
- null
- Freshness
- null
- Geography
- Global ocean coverage.