The California Current, on eastern rim of subtropical gyre, is characterized by broad, shallow near-surface flow to the south overlying a narrow, deep Undercurrent to the north. Upwelling is prevalent. Similar circumstances are seen in the southern Beaufort Sea where surface flow is broadly westward over narrow, eastward undercurrent. Indeed such flow regimes are repeated throughout the world's oceans. Why? Classical mechanics, the basis for modern ocean dynamics, solves for fluids that are pushed and pulled, hence for what "pushes" any current. Statistical mechanics, treating the aggregate of innumerable "mechanical" interactions, reveals collective behavior beyond pushes and pulls. We consider California Current regimes (worldwide) from statistical mechanical perspective.