Coastal Upwelling Nutrient Pump

Coastal upwelling doesn't just move water — it moves the nutrients that fuel the entire coastal food web. This simulation models a vertical water column beneath an upwelling zone: wind-driven upwelling advects deep, nitrate-rich water toward the surface, where sunlight lets phytoplankton turn that nutrient supply into biomass. Light fades exponentially with depth while nutrient supply comes from below, so growth is squeezed into a band where both are adequate — producing a subsurface chlorophyll maximum whose depth shifts live as you change upwelling strength, water turbidity, mixed-layer depth and grazing pressure. Live readouts track surface nitrate, the chlorophyll-maximum depth and integrated net primary production as the column evolves toward its steady state.