🌊 Wind-Driven Ocean Gyres in 3D: Sverdrup Balance, Western Boundary Current and Heat Transport (Stommel Basin)

A 3D ocean basin where wind stress curl drives subtropical and subpolar gyres. A beta-plane Stommel model is solved live, shows the Gulf-Stream-like western boundary current, advects warm and cold water, measures poleward heat transport and adds a two-box overturning model with freshwater hysteresis; checked against the exact Stommel solution.