MAUMERE, NTT – The serene, tri-colored lakes of Mount Kelimutu, a crown jewel of Indonesian tourism located in the Ende Regency of East Nusa Tenggara (NTT), are currently masking a volatile geological transformation. On May 24, 2024, the Geological Agency of the Indonesian Ministry of Energy and Mineral Resources (ESDM) officially elevated the status of the Kelimutu volcano from Level I (Normal) to Level II (Waspada/Alert). This decision follows a series of concerning visual and instrumental observations that suggest the stratovolcano is experiencing an internal shift, heightening the risk of sudden eruptions. Authorities have issued a firm directive to the public, local residents, and international tourists alike: maintain a safe distance of at least 250 meters from the crater rims to avoid the potential impact of volcanic ejecta. The Core Threat: Understanding the Volcanic Danger The escalation to Level II (Alert) is not merely a bureaucratic measure; it is a response to the inherent volatility of Kelimutu’s current state. According to Irwan Ka Uman, Head of the Kelimutu Volcano Observation Post, the primary threats currently facing the area are the risks of phreatic and magmatic eruptions. The Mechanism of Risk An eruption at Kelimutu, should it occur, would likely manifest in two distinct forms: Phreatic Eruptions: These occur when magma beneath the surface heats groundwater or surface water. The temperature differential is so extreme that the water turns into steam almost instantaneously. This rapid expansion creates a high-pressure explosion that can eject steam, hot water, ash, rock fragments, and volcanic "bombs" without the typical precursor of rising lava. Magmatic Eruptions: More severe in nature, these occur when molten magma from deep within the earth’s crust pushes upward to the surface. Unlike phreatic events, these involve the direct expulsion of fresh volcanic material, signaling a deeper and more sustained period of geological unrest. The danger extends beyond the immediate crater rim. Meteorologists and volcanologists warn that in the event of an eruption, ashfall could travel significant distances, with the intensity and reach of the fallout dictated by wind speed and direction at the time of the event. Chronology of Escalation: From Serenity to Alert The transition to a "Waspada" status did not happen overnight. It is the culmination of weeks of heightened monitoring by the Volcanology and Geological Hazard Mitigation Center (PVMBG). The Indicators of Change In the weeks leading up to the May 24 announcement, observers stationed at the Kelimutu observation post noted significant anomalies in the volcano’s three iconic crater lakes: Tiwu Ata Polo (Kawah I), Tiwu Koofai Nuwamuri (Kawah II), and Tiwu Ata Bupu (Kawah III). Mid-May 2024: Observers noted a shift in the chemistry and appearance of the lakes. Kawah I, traditionally known for its color-shifting properties, began displaying a dark, brownish-black hue, accompanied by visible bubbles on the northeastern surface—a sign of increased gas discharge. Late-May 2024: Kawah II, the light-blue crater, exhibited a marked increase in sulfur deposits. Yellowish sulfur crusts were seen spreading from the center of the lake toward the southeast and southern shores, indicating an intensification of thermal activity beneath the lakebed. Systemic Monitoring: By analyzing seismic data alongside visual observations, the Geological Agency concluded that the volcano was no longer in a state of stable equilibrium. The decision to raise the alert level was finalized on May 24, 2024, to ensure public safety in the face of these erratic, but significant, geochemical changes. Supporting Data: The Anatomy of Kelimutu’s Lakes To understand the gravity of the current situation, one must understand the unique nature of Mount Kelimutu. It is a stratovolcano, characterized by its conical shape and layers of hardened lava, tephra, and volcanic ash. Its three lakes are not just tourist attractions; they are dynamic geochemical laboratories. Current Visual Assessment The Geological Agency’s latest report provides a detailed breakdown of the current state of the three lakes: Tiwu Ata Polo (Kawah I): Currently displays a dark brownish-black color. The detection of sulfur gas odors, though weak, coupled with the persistent bubbling on the surface, suggests a steady release of gases from the magma chamber below. Tiwu Koofai Nuwamuri (Kawah II): This lake, which often displays a striking turquoise color, is now heavily laden with sulfur. The widespread appearance of light yellow sulfur deposits on the water’s surface is a clear indicator that the lake is undergoing significant chemical alteration due to hydrothermal heating. Tiwu Ata Bupu (Kawah III): While the most stable of the three, it currently exhibits a deep green color, which experts continue to monitor for any signs of temperature spikes. The interplay between these lakes and the underlying volcanic conduit is the primary focus of the monitoring teams. Any rapid change in the water’s acidity or temperature could act as a final precursor to a phreatic explosion. Official Responses and Public Safety Mandates The Geological Agency has acted decisively to mitigate risks to the local population and the thousands of tourists who visit Kelimutu annually. Directives for Visitors and Residents The 250-Meter Exclusion Zone: This is the most critical recommendation. Visitors are strictly prohibited from entering the area within a 250-meter radius of the crater rims. This distance is calculated based on the potential range of ballistic projectiles (volcanic rocks and debris) that could be thrown during a phreatic event. Preparedness for Ashfall: Residents living in the surrounding villages of Ende Regency are urged to remain calm but vigilant. The Agency has recommended that the local government and community leaders prepare masks and eye protection, as wind patterns could carry volcanic ash toward residential areas depending on meteorological shifts. Enhanced Monitoring: The Kelimutu Observation Post has moved to a 24-hour monitoring schedule. Data from seismic sensors, tiltmeters (which measure ground deformation), and chemical water sampling are being transmitted in real-time to the Geological Agency in Bandung for expert analysis. "We urge the public to follow the instructions of the local authorities," stated Irwan Ka Uman. "Do not be tempted by the beauty of the landscape to ignore safety protocols. The volcano is a natural entity that does not always provide long-term warnings before an eruption." Implications: Tourism and Regional Stability The elevation of Kelimutu to "Waspada" status brings immediate implications for the regional tourism sector of East Nusa Tenggara. The Economic Impact Tourism is the lifeblood of the Ende Regency. The Kelimutu National Park is a major destination for both domestic and international travelers. Travel agencies and tour operators have been advised to adjust their itineraries. While the park is not entirely closed, the restriction of movement around the craters may limit the typical "summit experience" that many tourists seek. Local government officials are working closely with the Ministry of Tourism to provide accurate, transparent information to travel stakeholders. The goal is to prevent panic while ensuring that safety is not compromised for the sake of revenue. Environmental and Geopolitical Context Mount Kelimutu’s current activity serves as a reminder of Indonesia’s position on the "Pacific Ring of Fire," a horseshoe-shaped belt of high volcanic and seismic activity. The country is home to over 120 active volcanoes, and the management of these sites requires a delicate balance between geological research, public safety, and economic dependency. The current situation at Kelimutu is expected to remain in flux for the foreseeable future. The Geological Agency has committed to providing regular, updated bulletins as new data emerges. For now, the message remains clear: the mountain is restless, and respect for its volatile nature is the only way to ensure the safety of those who live in its shadow. Conclusion As of late May 2024, the situation at Mount Kelimutu is defined by caution. The combination of increased sulfur emissions, erratic color changes, and the potential for explosive phreatic activity necessitates a disciplined approach from all stakeholders. Whether this period of "Waspada" will lead to a full eruption or return to a state of dormant stability remains to be seen. In the meantime, the scientific community and the people of Ende remain on high alert, watching the tri-colored lakes for the next sign of what lies beneath the earth’s surface. Source: Antara / Geological Agency of the Ministry of Energy and Mineral Resources (ESDM) Post navigation Rocket Lab Launches NASA’s PREFIRE Satellite: A New Era in Climate Observation Fortifying Resilience: Indonesia Deploys Advanced Early Warning Systems Following Devastating West Sumatra ‘Galodo’
