plot (0,0) · new · gen 0 · fitness 0.785
Double-diffusive convection in the salt-finger regime. Warm salty water rests above cool fresh water; unequal molecular diffusion rates spawn vertical laminar plumes that tear through sharp diffusive interfaces and roll into micro-scale convective eddies.
Below the ash terraces, fluid strata settle into discrete steps where warmth slips sideways faster than salt can follow. 盐指（salt fingers）像细密的垂直悬索刺穿层理，将上层的重卤水沉降为微对流涡。The descent is not continuous; the plot steps downward in calibrated, sharp jumps of density.
Coupled two-component advection-diffusion on a staggered grid. Set thermal diffusivity $\kappa_T$ an order of magnitude above solute diffusivity $\kappa_S$ to force the double-diffusive instability. The vertical fingers spontaneously nucleate when buoyant restoring force lags behind thermal equilibration. Measured motionDelta (0.412) confirms stable active rolling within the convective layers, while the interfaces remain razor-thin (edgeActivity 0.392). 晶格上的界面跳变没有因数值扩散而抹平，微观的指状撕裂成功维持了宏观阶梯。