South African design collective EarthCode clinched two Gold Cannes Lions for "Dune Archives," transforming False Bay coastline into living data repositories. Commissioned by Oceanographic Research Institute, solar-powered drones engrave real-time marine metrics onto windward dune faces: tidal amplitude manifests as undulating ridges (2cm = 1m swell), while microplastic concentrations alter quartz density gradients visible under polarized lenses. At dusk, phosphorescent algae injected along etchings emit cyan luminescence correlating to coral health alerts. 

Visitors decode ecological narratives via augmented reality driftwood viewers, where touch-activated holograms overlay bleaching forecasts onto physical inscriptions. Coastal rangers documented 53% increase in citizen science reporting during deployment, while drone-captured thermal imagery confirmed 28% cooler sand temperatures at engraved sites due to controlled airflow. 

"Each dune becomes a geological hard drive preserving oceanic memory," stated geodata artist Liam Botha. Singapore’s PUB Water Agency now adapts the technique for reservoir sedimentation tracking using bioluminescent fungi instead of algae.