The sigma coordinate system is a common coordinate system used in computational models for oceanography, meteorology and other fields where fluid dynamics are relevant.[1] This coordinate system receives its name from the independent variable used to represent a scaled pressure level.
Models that use a sigma coordinate system include the Princeton Ocean Model (POM),[2] the COupled Hydrodynamical Ecological model for REgioNal Shelf seas (COHERENS)[1], the ECMWF Integrated Forecast System, and various other numerical weather prediction models.