Residents on the coast of Sarmi and Biak Numfor regencies were briefly struck by anxiety following the appearance of millions of floating pumice stones covering the sea surface. The volcanic material floated with high density, creating a sight resembling a new landmass and sparking speculation among the public about active undersea volcanic activity in Papua waters.
Responding to these concerns, the Head of the BMKG Maritime Meteorology Station in Jayapura, Heri Purnomo, provided a firm clarification. Based on satellite imagery monitoring and maritime coordination analysis, the pumice was confirmed not to originate from geological activity within Indonesian territory, but was instead material carried from an underwater volcanic eruption in the Bismarck Sea region, Papua New Guinea, which occurred starting June 8, 2026.
Heri explained that pumice has a very low density characteristic because it forms from the solidification of gas-rich magma. This material was carried by ocean surface currents consistently moving westward, passing through the Swanggara Strait until finally washing up heavily along the northern coast of Papua. He reiterated that there is no record of underwater volcanic activity in Indonesian waters, urging the public not to fall for inaccurate information.
Although not directly threatening like a volcanic eruption itself, this phenomenon brings ecological and technical impacts that require vigilance. The accumulated material risks causing coastal shoaling, disrupting coral reef ecosystems, and polluting fish spawning habitats as well as mangrove forests in bay areas.
In addition to environmental threats, BMKG also highlighted risks to maritime navigation. Pumice debris sucked into engine cooling intakes or striking ship propellers could cause technical damage to fishing boats and other maritime transport. Therefore, maritime authorities and fishermen along the coast from Sarmi to Biak are advised to remain vigilant while at sea until water conditions return to normal.
