Hawaii natural sea arch collapses into Pacific after standing for roughly 550 years
A well-known natural sea arch along Hawaii’s coastline collapsed into the Pacific Ocean this week without warning, ending a roughly 550-year run as both a geological landmark and a tourist draw. The arch had been carved from volcanic rock by centuries of wave and salt weathering, and its loss has renewed discussion among researchers and the public about how fast coastal landforms evolve, whether sea-level rise is accelerating erosion, and how complete the human record of such long geological processes can ever be.