The Changing Color of Kelimutu Lakes, It Is Unpredictable

The transformation stems from chemical reactions within the volcanic crater. Fumaroles—vents releasing steam and gases like sulfur dioxide—stir the lake waters from below. This upwelling brings mineral-rich, oxygen-poor water to the surface, altering how light reflects off dissolved metals like zinc and lead. When oxygen levels rise, the lakes can turn blood red or dark brown—similar to how hemoglobin changes color in human blood.

Satellite images from NASA reveal just how dynamic Kelimutu is. Between 2014 and 2017, the lakes shifted visibly in color and pattern. Reports from The Jakarta Post noted six changes in 2016 alone. Yet, according to Indonesia’s Volcanology and Geological Disaster Mitigation Center (PVMBG), these shifts don’t signal increased volcanic risk. The area remains safe—and deeply compelling—for travelers.