Ancient crystal growths in caves reveal seas rose 16 meters in a warmer world

Findings on the Spanish coast of Mallorca hint at how oceans could respond to climate change

stalactites

Giant rock formations inside Spain’s Artà Caves reveal how high seas once rose. Bulbous formations grew onto stalactites where brackish water lapped at the rock 4.39 million years ago.

Antoni Merino

The future of sea level rise may be written into the walls of coastal Spanish caves.