Indonesia Volcano Tracker β Live Eruptions & Alerts
By Paul Harrison | Founder & Publisher, Orbis Weather
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Indonesia Volcanoes and Live Eruptions This Week: Saturday, November 7, 2026
Β· @Paul
By Paul Harrison, Orbis Weather
Six Indonesian volcanoes erupted in the week from Saturday, October 31 to Saturday morning, November 7, 2026: Semeru, Merapi, Karangetang, Dukono, Ibu and Bromo. Semeru and Merapi, both on Java, remain at Level III (Siaga), the second-highest of four alert levels. This report is current to 06:00 WIB on Saturday, November 7 (18:00 EST on Friday, November 6).
The most notable eruption came on Friday afternoon, November 6, when Semeru sent a pyroclastic flow down the Besuk Kobokan valley in Lumajang, East Java, and fired its tallest ash column of the week. Semeru erupted again at 01:23 WIB on Saturday. No deaths, injuries, evacuations or flight disruptions were reported for any of this week’s eruptions.
Key facts
Measure | This week |
|---|---|
Volcanoes erupting | 6 |
Highest alert level | Level III (Siaga): Semeru and Merapi |
Most notable eruption | Semeru, Friday afternoon, November 6, with a pyroclastic flow into Besuk Kobokan |
Deaths, injuries or evacuations | None reported |
Flight disruption | None reported |
Alert levels at a glance
Volcano | Region | Alert level | Keep-out zone | This week’s activity |
|---|---|---|---|---|
Semeru | East Java | III (Siaga) | 5 km radius; 13 km to the southeast along Besuk Kobokan | Repeated eruptions November 5 to 7, with pyroclastic flows |
Merapi | Central Java / Yogyakarta | III (Siaga) | 3 to 7 km, depending on river valley | Continuing lava-dome growth and lava avalanches |
Karangetang | Siau Island, North Sulawesi | II (Waspada) | 1.5 km from both craters; 2.5 km to the south-southwest | Eruptions on November 1 and 5, lava avalanches |
Dukono | Halmahera, North Maluku | II (Waspada) | 4 km from the Malupang Warirang crater | Eruptions on November 2 and 3 |
Ibu | Halmahera, North Maluku | II (Waspada) | 2 km from the crater; 3.5 km to the north | Eruption at 16:59 WIT on November 2, ash 500 m above the summit (1,825 m above sea level), drifting west |
Bromo | East Java | II (Waspada) | 1 km from the crater | Eruption at about 17:11 WIB on November 5, ash 500 m above the summit, drifting west |
Other volcanoes remain above normal. Ili Lewotolok (Lembata, East Nusa Tenggara) was last confirmed at Level II in late October, with ash plumes on October 24, and Marapi (West Sumatra) was at Level II with an eruptive event on October 26. Anak Krakatau was lowered to Level II on September 21 and Lewotobi Laki-laki on September 16; Sinabung (North Sumatra) was last confirmed at Level III in a September 14 report, having been raised on August 31.
Volcanoes erupting this week
Semeru, East Java
Semeru was the most active volcano of the week, producing two pyroclastic flows on Friday afternoon alone. A pyroclastic flow (awan panas guguran) is a fast, ground-hugging avalanche of hot ash, gas and rock.
- November 5, 09:24 WIB: ash rose about 700 m above the summit (4,376 m above sea level), and a pyroclastic flow ran about 4.5 km to the southeast. The seismograph recorded a maximum amplitude of 31 mm over 7 minutes 27 seconds.
- November 6, 00:35 to 08:37 WIB: six eruptions, with ash 400 to 700 m above the summit drifting southwest.
- November 6, 15:48 WIB: the week’s tallest column, about 1,000 m above the summit (4,676 m above sea level). A pyroclastic flow travelled about 5 km southeast into Besuk Kobokan. Amplitude 23 mm, duration 744 seconds.
- November 6, 16:57 WIB: ash about 500 m above the summit (4,176 m above sea level) and a second pyroclastic flow of about 4 km to the southeast.
- November 7, 01:23 WIB: ash about 200 m above the summit (3,876 m above sea level), drifting southwest. Amplitude 22 mm, duration 147 seconds.
Beyond the keep-out zones in the table above, people must stay 500 m back from the Besuk Kobokan riverbanks as far as 17 km from the summit, because pyroclastic flows and lahars can spread along the valley.
Merapi, Central Java and Yogyakarta
Merapi continued a slow, effusive eruption, in which lava oozes out to build a dome that sheds glowing lava avalanches rather than exploding. BPPTKG head Agus Budi Santoso said on October 31 that Merapi’s “volcanic activity is still quite high, in the form of effusive eruption,” and that ongoing magma supply could trigger pyroclastic flows within the danger zone.
- November 2 report: five lava avalanches ran up to 1,600 m southwest toward Kali Sat, Kali Putih and Kali Krasak, and one reached 1,700 m into Kali Krasak.
- November 3 (24 hours): six lava avalanches up to 1,500 m southwest, with 66 avalanche earthquakes, 58 hybrid earthquakes and 17 shallow volcanic earthquakes.
- November 6 (24 hours): one lava avalanche ran 1,200 m toward Kali Sat/Kali Putih. BPPTKG recorded 47 avalanche and 52 hybrid earthquakes, and white emissions reached 325 m above the summit.
Danger zones run to 5 km along the Boyong, 7 km along the Bedog, Krasak and Bebeng, 3 km along the Woro and 5 km along the Gendol. An explosive eruption could throw material 3 km from the summit.
Karangetang, Siau Island, North Sulawesi
Karangetang produced explosive eruptions and lava avalanches from its north crater. On November 1 it erupted at 19:23, 19:38 and 21:18 WITA; the last had a maximum amplitude of 50 mm and threw incandescent material 200 to 300 m around the summit, with a smoke column about 1,000 m high leaning west and northwest. Lava avalanches flowed 200 to 700 m south, 700 to 1,000 m west and southwest, and 500 to 700 m northwest. On November 5, an eruption at 13:14 WITA sent ash about 800 m above the crater, drifting south and southwest. Observers warned that lahars could reach the coast along river valleys.
Dukono, Halmahera, North Maluku
Dukono erupted five times in the week to November 3. On November 2, an eruption at 09:11 WIT sent ash about 950 m above the summit (2,037 m above sea level), drifting west, followed by a second at 09:53 WIT whose column was hidden by cloud. Another eruption followed at 12:15 WIT on November 3, when 12 eruption earthquakes were recorded over the day.
Ash and aviation
Semeru’s Friday afternoon column, at roughly 15,300 ft above sea level, was the highest ash top reported this week; the other eruptions reached between about 1,800 m and 4,400 m above sea level. Ash from Semeru drifted mainly south, southeast and southwest, and from Dukono, Ibu and Bromo to the west. No airport closures, cancelled flights or diverted aircraft were reported in coverage of this week’s eruptions. Aircraft over Indonesia receive ash warnings from the Darwin Volcanic Ash Advisory Centre (VAAC) and from PVMBG’s VONA notices.
What to watch in the coming week
- Semeru pyroclastic flows and lahars: further flows down Besuk Kobokan, and rain-driven lahars (volcanic mudflows) along the Besuk Kobokan, Besuk Bang, Besuk Kembar and Besuk Sat valleys.
- Merapi lava avalanches: BPPTKG has warned residents to watch for lahars and pyroclastic flows, especially during rain. Its next weekly summary covers Friday to Thursday.
- Karangetang lahars: unstable lava piles on the upper slopes could collapse, and lahars could reach the coast along river valleys.
- Halmahera ash: Dukono and Ibu have erupted repeatedly at Level II; nearby residents have been advised to carry masks.
- Bromo visitors: PVMBG has warned that sudden steam-driven eruptions can occur without clear warning signs; the 1 km crater limit applies to tourists.
How Indonesia’s volcano alert system works
Level | Name | What it means |
|---|---|---|
I | Normal | Background activity; no eruption expected |
II | Waspada (Advisory) | Activity above normal; small eruptions possible near the crater |
III | Siaga (Watch) | Clear rise in activity; a larger eruption is possible, so wider zones are closed |
IV | Awas (Warning) | A major eruption is under way or imminent; evacuation of danger zones |
Levels are set by PVMBG, the Centre for Volcanology and Geological Hazard Mitigation, part of the Geological Agency (Badan Geologi) in the Ministry of Energy and Mineral Resources; BPPTKG monitors Merapi on its behalf.
About this article
This is a summary of published reports from PVMBG, BPPTKG, the Smithsonian Global Volcanism Program and Indonesian news outlets, not an official warning; people near a volcano should follow PVMBG and local authorities. Event times are local: WIB (UTC+7) for Java, WITA (UTC+8) for North Sulawesi and WIT (UTC+9) for North Maluku. Eruption counts differ between sources because some count every seismic eruption signal while others count only eruptions seen by observers, and reporting periods vary. Ash heights are estimates by ground observers and are often missed in cloud or darkness.
Glossary
- Pyroclastic flow (awan panas guguran): a fast-moving avalanche of hot ash, gas and rock.
- Lava avalanche (guguran lava): glowing blocks breaking off a lava dome and rolling downslope.
- Lahar: a volcanic mudflow, usually triggered by rain on loose ash.
- Hybrid earthquake: a volcanic quake linked to rising magma, often watched at Merapi.
- Seismic amplitude: the size of the trace an eruption leaves on a seismograph, given in millimetres.
Frequently asked questions
Which Indonesian volcano is the most active right now? Semeru in East Java was the most active this week, with repeated ash eruptions and two pyroclastic flows on November 6. It has been at Level III since January 2026.
Is any Indonesian volcano at the highest alert level? No volcano was reported at Level IV (Awas) this week. Semeru and Merapi are at Level III, and the other erupting volcanoes are at Level II.
Is it safe to fly to Bali or Java? No airport closures or flight cancellations were reported this week. Travellers should still check with their airline, because ash drift can change quickly with the wind.
Can tourists visit Bromo? Bromo’s tourism area remained open after the November 5 eruption, but visitors must stay outside the marked crater limit. Park managers say they follow PVMBG recommendations, which can change at short notice.
Why do reports give two different ash heights? PVMBG gives the height above the summit, and often a second figure above sea level, which adds the volcano’s elevation. Aviation advisories use the above-sea-level figure, usually in feet.
Sources
- Antara: Semeru pyroclastic flow of 5 km (November 6)
- Antara: Semeru erupts with 200 m column, Saturday early morning (November 7)
- CNN Indonesia: Semeru pyroclastic flow of 4.5 km (November 5)
- CNBC Indonesia: Semeru ash column 1,000 m (November 6)
- Jawa Pos: Six Semeru eruptions on Friday morning (November 6)
- JPNN Jogja: Merapi weekly report, nine lava avalanches (October 31)
- Radar Jogja: Merapi lava avalanche 1,700 m to Kali Krasak (November 2)
- Radar Jogja: Merapi activity, November 3 (November 4)
- Radar Jogja: Merapi activity, November 6 (November 7)
- Tribun Jogja: Merapi activity report, November 6
- Viva: Karangetang lava avalanches to 1 km (November 1)
- Harian Jogja: Karangetang erupts three times (November 2)
- Antara: Karangetang ash column 800 m (November 5)
- Suara: Dukono erupts twice in 42 minutes (November 2)
- Databoks: Dukono erupts again (November 3)
- Bloomberg Technoz: Ibu ash 500 m, Level II (November 2)
- Seantero News: Bromo erupts, ash 500 m (November 6)
- The Watchers: Smithsonian/USGS Weekly Volcanic Activity Report, October 22 to 28
- detikFinance: Anak Krakatau lowered to Level II (September 22)
- RCTI+: Lewotobi Laki-laki lowered to Level II (September 16)
- detik: Volcanoes at Siaga, including Sinabung and Semeru (September 7)
- Harian Jogja: 11 volcanoes erupted in 2026, alert levels (September 14)
π¦ Indonesia's Official Volcano Alert Levels
π Volcanoes to Watch
β οΈ Main Volcanic Hazards
π Official Live Volcano Status
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Β
Indonesia Volcano Tracker: Current Activity, Eruptions & Volcanic Hazards
Indonesia is one of the most volcanically active countries on Earth. From the densely populated islands of Java and Sumatra to the volcanic chains of Bali, Flores, Sulawesi and the Maluku Islands, eruptions are a regular part of life across the Indonesian archipelago.
The Indonesia Volcano Tracker from Orbis Weather is designed to help readers follow volcanic activity across the country in one place. Use the live tracker above to identify volcano locations and monitor areas where volcanic unrest or eruptions may be occurring.
Volcanic conditions can change quickly. An apparently quiet volcano can experience increased earthquakes, gas emissions or other signs of unrest, while an active eruption can produce ash clouds capable of traveling hundreds of miles from the volcano.
For official warnings, evacuation orders and exclusion zones, always follow Indonesian authorities and local emergency officials.
π Why Does Indonesia Have So Many Volcanoes?
Indonesia sits within one of the world’s great zones of tectonic and volcanic activity.
The country lies along several interacting tectonic plate boundaries where, in many areas, one plate is forced beneath another through a process called subduction. This can generate magma that eventually rises toward the surface and feeds volcanoes.
Indonesia is therefore commonly associated with the Pacific Ring of Fire, the broad collection of highly active volcanic and earthquake regions around much of the Pacific. The Smithsonian Institution’s Global Volcanism Program lists 101 Holocene volcanoes in Indonesia, meaning volcanoes with evidence of activity during roughly the past 12,000 years. (CF11)
This geology also helps explain why Indonesia experiences frequent earthquakes as well as volcanic eruptions.
π₯ Some of Indonesia’s Most Closely Watched Volcanoes
Indonesia has numerous volcanoes with histories of significant or persistent activity. Among the names frequently encountered in Indonesian volcano reports are Mount Merapi, Semeru, Ibu, Dukono, Lewotobi Laki-laki, Anak Krakatau and Agung.
Each volcano behaves differently.
Some can experience frequent smaller explosions and ash emissions, while others may remain relatively quiet for long periods before entering a period of renewed unrest. Past behavior does not guarantee what a volcano will do next, which is why monitoring earthquakes, deformation, gas emissions and other volcanic signals is so important.
The tracker above should therefore be viewed as a way to understand where volcanic activity is occurring, rather than as a prediction of exactly when the next major eruption will happen.
β οΈ Understanding Indonesia Volcano Alerts
Indonesia’s volcano monitoring authorities use alert levels to communicate changes in volcanic activity and the potential danger surrounding a volcano.
A higher alert level can result in expanded exclusion zones and recommendations for residents, tourists and climbers to stay farther from the crater or other hazardous areas.
An alert level does not mean that every location surrounding a volcano faces the same risk. Topography, wind direction, eruption type, rainfall and distance from the volcano can dramatically affect which communities are threatened.
Always check the latest instructions from Indonesian authorities before approaching an active volcano.
βοΈ Volcanic Ash and Air Quality
Volcanic ash is very different from the soft ash produced by a wood fire. It consists largely of tiny fragments of rock, minerals and volcanic glass.
Heavy ashfall can reduce visibility, contaminate water supplies, damage machinery and create dangerous driving conditions. Fine particles can also aggravate respiratory problems, particularly among vulnerable people. (U.S. Geological Survey)
Wind direction is extremely important during an eruption. Communities far from the crater can sometimes experience ashfall while locations much closer to the volcano remain relatively unaffected.
This is why an eruption’s impacts can extend well beyond the immediate exclusion zone.
βοΈ Why Indonesian Volcanoes Matter to Aviation
Indonesia’s location makes volcanic ash particularly important for aviation.
Aircraft flying through volcanic ash can suffer abrasion to windscreens and other surfaces, contamination of instruments and potentially serious engine problems. The U.S. Geological Survey notes that ash particles entering jet engines can melt and accumulate inside the engine, degrading performance and potentially causing a loss of thrust. (USGS)
Consequently, significant eruptions in Indonesia can result in flight diversions, delays or airport closures even when the airport itself is some distance from the erupting volcano.
Travelers should check official airline and airport information whenever a major Indonesian eruption is producing an ash plume.
π Pyroclastic Flows, Lahars and Volcanic Tsunamis
Ash isn’t the only danger associated with Indonesian volcanoes.
Pyroclastic flows are extremely hot, rapidly moving mixtures of volcanic material and gas that can travel down the sides of a volcano. They are among the most dangerous hazards associated with explosive eruptions.
Lahars are another major concern. These destructive flows can occur when water mixes with loose volcanic ash and debris. Heavy tropical rainfall means lahar hazards can sometimes persist after the main eruption has ended.
Indonesia’s island geography also creates another unusual threat: volcanic tsunamis. Under certain circumstances, the collapse of part of a volcanic island, landslides or volcanic activity entering the sea can displace water and generate dangerous waves.
The 2018 collapse of part of Anak Krakatau demonstrated the devastating potential of this type of event.
π§ What Should You Do During an Indonesian Volcanic Eruption?
If you’re near an erupting volcano, official evacuation instructions should take priority over information from websites, social media or unofficial maps.
Never enter an established exclusion zone simply because the volcano appears quiet.
During ashfall, stay indoors when authorities recommend doing so, protect drinking water and avoid unnecessary driving where visibility is poor or ash is accumulating. Travelers should monitor airline notices because volcanic ash can alter flight operations with little warning.
People living near river valleys draining an active volcano should also remain aware of lahar warnings, especially during periods of heavy rain.
π‘ How Scientists Monitor Indonesia’s Volcanoes
Scientists don’t rely on a single measurement to determine whether a volcano is becoming more active.
Monitoring can include earthquake activity beneath the volcano, ground deformation, volcanic gas emissions, thermal observations, satellite imagery and visual observations of the crater.
Changes in several of these signals can provide evidence that magma or volcanic gases are moving underground. However, volcano forecasting is complex. Increased unrest does not always lead to a major eruption, and the timing and size of an eruption cannot always be predicted precisely.
That’s why continuous monitoring is so important in a country with as many potentially active volcanic systems as Indonesia.
β Indonesia Volcano Tracker FAQ
How many volcanoes does Indonesia have?
The Smithsonian Global Volcanism Program currently lists 101 Holocene volcanoes associated with Indonesia. Different organizations may publish different totals because the definition of an “active volcano” can vary. (CF11)
Why are there so many volcanoes in Indonesia?
Indonesia lies across highly active tectonic regions where interacting plates and subduction create conditions favorable for magma formation and volcanic activity.
Can Indonesian volcanoes disrupt flights?
Yes. Volcanic ash can travel far downwind and represents a serious aviation hazard, potentially causing airlines to reroute or cancel flights. (USGS)
Can an Indonesian volcano cause a tsunami?
Yes, under certain circumstances. Volcanic flank collapses, landslides and other displacement of seawater can generate tsunamis.
Does volcanic unrest mean an eruption is definitely coming?
No. Increased earthquakes, gas emissions or deformation can indicate changing conditions beneath a volcano, but they do not guarantee that a major eruption will occur.
π Follow Southeast Asia’s Natural Hazards
Indonesia’s volcanoes are part of a much larger network of natural hazards affecting Southeast Asia. Earthquakes, tropical storms, monsoon flooding, volcanic eruptions, lightning and transboundary haze can all affect the region.
Continue exploring Orbis Weather’s Asia-Pacific trackers for Southeast Asia earthquakes, Singapore weather and natural hazards, haze and air quality, thunderstorms, monsoon flooding and other developing hazards across the region.
Data & Safety Note: Orbis Weather provides weather and natural-hazard information for educational and situational-awareness purposes. It should not replace official emergency warnings. During volcanic emergencies, follow instructions issued by Indonesian authorities, local disaster-management agencies and aviation authorities.
Β
Indonesia Volcano Tracker: Current Activity, Eruptions & Volcanic Hazards
Indonesia is one of the most volcanically active countries on Earth. From the densely populated islands of Java and Sumatra to the volcanic chains of Bali, Flores, Sulawesi and the Maluku Islands, eruptions are a regular part of life across the Indonesian archipelago.
The Indonesia Volcano Tracker from Orbis Weather is designed to help readers follow volcanic activity across the country in one place. Use the live tracker above to identify volcano locations and monitor areas where volcanic unrest or eruptions may be occurring.
Volcanic conditions can change quickly. An apparently quiet volcano can experience increased earthquakes, gas emissions or other signs of unrest, while an active eruption can produce ash clouds capable of traveling hundreds of miles from the volcano.
For official warnings, evacuation orders and exclusion zones, always follow Indonesian authorities and local emergency officials.
π Why Does Indonesia Have So Many Volcanoes?
Indonesia sits within one of the world’s great zones of tectonic and volcanic activity.
The country lies along several interacting tectonic plate boundaries where, in many areas, one plate is forced beneath another through a process called subduction. This can generate magma that eventually rises toward the surface and feeds volcanoes.
Indonesia is therefore commonly associated with the Pacific Ring of Fire, the broad collection of highly active volcanic and earthquake regions around much of the Pacific. The Smithsonian Institution’s Global Volcanism Program lists 101 Holocene volcanoes in Indonesia, meaning volcanoes with evidence of activity during roughly the past 12,000 years. (CF11)
This geology also helps explain why Indonesia experiences frequent earthquakes as well as volcanic eruptions.
π₯ Some of Indonesia’s Most Closely Watched Volcanoes
Indonesia has numerous volcanoes with histories of significant or persistent activity. Among the names frequently encountered in Indonesian volcano reports are Mount Merapi, Semeru, Ibu, Dukono, Lewotobi Laki-laki, Anak Krakatau and Agung.
Each volcano behaves differently.
Some can experience frequent smaller explosions and ash emissions, while others may remain relatively quiet for long periods before entering a period of renewed unrest. Past behavior does not guarantee what a volcano will do next, which is why monitoring earthquakes, deformation, gas emissions and other volcanic signals is so important.
The tracker above should therefore be viewed as a way to understand where volcanic activity is occurring, rather than as a prediction of exactly when the next major eruption will happen.
β οΈ Understanding Indonesia Volcano Alerts
Indonesia’s volcano monitoring authorities use alert levels to communicate changes in volcanic activity and the potential danger surrounding a volcano.
A higher alert level can result in expanded exclusion zones and recommendations for residents, tourists and climbers to stay farther from the crater or other hazardous areas.
An alert level does not mean that every location surrounding a volcano faces the same risk. Topography, wind direction, eruption type, rainfall and distance from the volcano can dramatically affect which communities are threatened.
Always check the latest instructions from Indonesian authorities before approaching an active volcano.
βοΈ Volcanic Ash and Air Quality
Volcanic ash is very different from the soft ash produced by a wood fire. It consists largely of tiny fragments of rock, minerals and volcanic glass.
Heavy ashfall can reduce visibility, contaminate water supplies, damage machinery and create dangerous driving conditions. Fine particles can also aggravate respiratory problems, particularly among vulnerable people. (U.S. Geological Survey)
Wind direction is extremely important during an eruption. Communities far from the crater can sometimes experience ashfall while locations much closer to the volcano remain relatively unaffected.
This is why an eruption’s impacts can extend well beyond the immediate exclusion zone.
βοΈ Why Indonesian Volcanoes Matter to Aviation
Indonesia’s location makes volcanic ash particularly important for aviation.
Aircraft flying through volcanic ash can suffer abrasion to windscreens and other surfaces, contamination of instruments and potentially serious engine problems. The U.S. Geological Survey notes that ash particles entering jet engines can melt and accumulate inside the engine, degrading performance and potentially causing a loss of thrust. (USGS)
Consequently, significant eruptions in Indonesia can result in flight diversions, delays or airport closures even when the airport itself is some distance from the erupting volcano.
Travelers should check official airline and airport information whenever a major Indonesian eruption is producing an ash plume.
π Pyroclastic Flows, Lahars and Volcanic Tsunamis
Ash isn’t the only danger associated with Indonesian volcanoes.
Pyroclastic flows are extremely hot, rapidly moving mixtures of volcanic material and gas that can travel down the sides of a volcano. They are among the most dangerous hazards associated with explosive eruptions.
Lahars are another major concern. These destructive flows can occur when water mixes with loose volcanic ash and debris. Heavy tropical rainfall means lahar hazards can sometimes persist after the main eruption has ended.
Indonesia’s island geography also creates another unusual threat: volcanic tsunamis. Under certain circumstances, the collapse of part of a volcanic island, landslides or volcanic activity entering the sea can displace water and generate dangerous waves.
The 2018 collapse of part of Anak Krakatau demonstrated the devastating potential of this type of event.
π§ What Should You Do During an Indonesian Volcanic Eruption?
If you’re near an erupting volcano, official evacuation instructions should take priority over information from websites, social media or unofficial maps.
Never enter an established exclusion zone simply because the volcano appears quiet.
During ashfall, stay indoors when authorities recommend doing so, protect drinking water and avoid unnecessary driving where visibility is poor or ash is accumulating. Travelers should monitor airline notices because volcanic ash can alter flight operations with little warning.
People living near river valleys draining an active volcano should also remain aware of lahar warnings, especially during periods of heavy rain.
π‘ How Scientists Monitor Indonesia’s Volcanoes
Scientists don’t rely on a single measurement to determine whether a volcano is becoming more active.
Monitoring can include earthquake activity beneath the volcano, ground deformation, volcanic gas emissions, thermal observations, satellite imagery and visual observations of the crater.
Changes in several of these signals can provide evidence that magma or volcanic gases are moving underground. However, volcano forecasting is complex. Increased unrest does not always lead to a major eruption, and the timing and size of an eruption cannot always be predicted precisely.
That’s why continuous monitoring is so important in a country with as many potentially active volcanic systems as Indonesia.
β Indonesia Volcano Tracker FAQ
How many volcanoes does Indonesia have?
The Smithsonian Global Volcanism Program currently lists 101 Holocene volcanoes associated with Indonesia. Different organizations may publish different totals because the definition of an “active volcano” can vary. (CF11)
Why are there so many volcanoes in Indonesia?
Indonesia lies across highly active tectonic regions where interacting plates and subduction create conditions favorable for magma formation and volcanic activity.
Can Indonesian volcanoes disrupt flights?
Yes. Volcanic ash can travel far downwind and represents a serious aviation hazard, potentially causing airlines to reroute or cancel flights. (USGS)
Can an Indonesian volcano cause a tsunami?
Yes, under certain circumstances. Volcanic flank collapses, landslides and other displacement of seawater can generate tsunamis.
Does volcanic unrest mean an eruption is definitely coming?
No. Increased earthquakes, gas emissions or deformation can indicate changing conditions beneath a volcano, but they do not guarantee that a major eruption will occur.
π Follow Southeast Asia’s Natural Hazards
Indonesia’s volcanoes are part of a much larger network of natural hazards affecting Southeast Asia. Earthquakes, tropical storms, monsoon flooding, volcanic eruptions, lightning and transboundary haze can all affect the region.
Continue exploring Orbis Weather’s Asia-Pacific trackers for Southeast Asia earthquakes, Singapore weather and natural hazards, haze and air quality, thunderstorms, monsoon flooding and other developing hazards across the region.
Data & Safety Note: Orbis Weather provides weather and natural-hazard information for educational and situational-awareness purposes. It should not replace official emergency warnings. During volcanic emergencies, follow instructions issued by Indonesian authorities, local disaster-management agencies and aviation authorities.