What are Events and Gradient Regions (E-GRs)?

We think of events mainly as mesoscale phenomena with markedly temporal signatures (such as shelf upwelling, biological blooms, hypoxia, and tidal-induced pulsing of plume and estuarine circulation). We think of gradient regions as predominantly spatial features associated with high functional gradients: examples include ‘river-to-ocean gradients’ (as defined by salinity), plume and estuarine fronts, and estuarine turbidity maxima. Of course, most E-GRs have both spatial and temporal gradients.