Reef Ribbons across the Coral Sea

Reef Ribbons across the Coral Sea is an original illustration set in Great Barrier Reef, Queensland, Australia. It lies in the tropics, where the climate is tropical savanna — a pronounced dry season.

From high above, long turquoise reef ribbons and rounded coral patches repeat across dark blue sea. White surf traces the exposed ocean-facing edges, shallow sand cays glow cream inside protected water, and one tiny boat and wake reveal the immense scale.

Why do pale reef ribbons repeat along the edge of deep blue ocean?

Coral communities grow best in warm, sunlit shallow water, so reef crests follow submerged platforms near the continental shelf rather than spreading across the deep ocean. Waves break first on the outer edge, while calmer lagoons behind collect pale carbonate sand and host patch reefs. Repeated bands of deep blue, surf white, turquoise shallows and sand therefore map changing depth and wave exposure without a drawn diagram.

Terpano is a free daily geography puzzle. You study one original illustration, place a pin on a borderless terrain map, and see how close you were. There is no account and no sign-up; progress stays in your own browser. It plays in 11 languages.