Satellite Tracking & Trajectory Modeling: How Science Predicts Sargassum Strandings

Forecasting sargassum arrivals requires combining Earth observation satellites orbiting 700 km overhead with complex hydrodynamic ocean models.

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Optical Remote Sensing: Detecting Floating Forests

Because sargassum contains high chlorophyll concentrations, it displays strong spectral reflectance in the Near-Infrared (NIR) spectrum:

• Alternative Floating Algae Index (AFAI): Developed by the University of South Florida (USF) using MODIS and OLCI (Sentinel-3) imagery to map macro-aggregations across the Atlantic.
• High-Resolution Sentinel-2 (10m): Pinpoints nearshore slicks 24 to 48 hours before coastal impact.

Hydrodynamic Drift Simulation

Once a biomass raft is identified:

1. Surface Ocean Currents: HYCOM and Mercator Ocean models simulate the main conveyor currents.
2. Wind Forcing (Stokes Drift): Direct trade wind drag pushes the buoyant floating mats at roughly 1% to 3% of ambient wind speed.
3. Probabilistic Risk Alerts: Daily 3-day and 7-day landing forecasts are published to guide municipal response teams.