Ocean Fishing Data Glossary
Eight terms, one definition-first page each, covering the satellite ocean-data vocabulary anglers run into most: what a satellite actually measures, how a pass differs from a composite, and the ocean features the charts are built to reveal.
Terms
- SST
- Sea surface temperature: the temperature of the ocean's surface, measured by satellite.
- Satellite pass
- One satellite's single overflight: real measurements, real gaps where cloud blocked the view.
- Composite
- A blended, gap-filled daily analysis built from multiple satellite passes.
- Temperature break
- A sharp boundary where two water masses of different temperature meet.
- Chlorophyll edge
- A sharp boundary between clear water and chlorophyll-rich water.
- Upwelling
- Wind-driven rise of cold, nutrient-rich water from depth to the surface.
- Eddy
- A rotating loop of water that has broken away from a larger current.
- Secchi depth
- How far down a plain white disk stays visible: the standard water-clarity measurement.
Want the full explanation behind a term, not just the definition? Start at the complete guide to satellite fishing charts or browse the rest of Learn. See it on real water on the SST map.