SINGAPORE - Three decades after Mount Pinatubo in the Philippines billowed enough ash to blanket Singapore and cut out enough sunlight worldwide to cool the Earth for years, Nanyang Technological University (NTU) scientists are looking into how the Republic can better prepare for future eruptions.
The eruption on June 15, 1991 - the world's largest in the past 100 years - sent ash to Singapore on the evening of June 17. The ash hung in the air here for three weeks before clearing, with some people reporting allergic reactions.
A plane flying from Changi to Osaka, Japan, was reportedly damaged after being caught in an ash cloud for 30 minutes.
Given the higher operating temperatures of jet engines today, ash particles can easily melt onto engine parts, affecting their function, and flights may have to be suspended should a similar eruption happen, said scientists.
Had there not been a typhoon in the Philippines at the same time, more ash would have travelled to Singapore and the impact here may have been more severe.
A 2015 paper put the chances of another Pinatubo-like eruption in South-east Asia occurring in any decade at 15 per cent.
Singapore is nestled close to the Pacific Ring of Fire, where Indonesia - which has more volcanoes than any other country - sits.
"Given that a typhoon with an eruption is a low-probability event, we would expect more ash if such an event were to happen again," said Assistant Professor Susanna Jenkins from the volcano group at NTU's Earth Observatory of Singapore (EOS).
The scientists aim to anticipate and forecast eruptions in South-east Asia so that the impact on infrastructure, the economy and health can be mitigated.
Said EOS volcano group leader Fidel Costa: "We cannot stop the eruptions, but we can prepare for them by using a wide range of monitoring tools, experiments and data from fieldwork."
Many car owners in several areas in Singapore discovered a layer of ash or dust settled on their cars. PHOTO: THE NEW PAPER
The scientists' research will look at how the country can better forecast eruptions of such a scale so that the authorities can be advised on mitigation measures.
For one thing, Prof Jenkins is looking to simulate how a major volcanic eruption, and a big earthquake or tsunami in South-east Asia will impact Singapore.
"So if it is an explosive eruption in Sumatra, for example, we would try to figure out when and how the ash would reach Singapore, and the effects on our airspace and supply routes," said Prof Jenkins.
Compared with 30 years ago, a more modernised Singapore is now widely reliant on technological equipment in areas such as transport, water treatment and power networks.
Even the ubiquitous air-conditioners may not be spared.
Fine ash from an eruption can infiltrate more deeply into electrical equipment, upending infrastructure and the aviation scene, said Prof Jenkins.
"Damp ash less than 3mm thick can cause short-circuiting on electrical networks, and ash particles can have acidic coatings that can cause corrosion or water-quality issues."
Studying the impact of eruptions on smart cities is a developing research area which needs post-eruption studies, experiments and calculations, she added.
For instance, said Prof Jenkins, a lab experiment could entail continuously running an air-conditioning unit exposed to airborne ash to find out at what point the filters clog and need replacing.
The eruption on June 15, 1991, sent ash to Singapore on the evening of June 17. PHOTO: U.S. GEOLOGICAL SURVEY (USGS)
"From experiments like this, we can have a better understanding of the actions needed, such as stockpiling more air-con filters, if such an event happens," she said.
For humans, exposure to ash may worsen health conditions such as asthma.
"Fine ash can penetrate deeper into the lungs. Unlike haze, volcanic ash is made up of sharp, crystalline glass and rock particles, so the impacts are not the same," said Prof Jenkins.
Associate Professor Benoit Taisne is the monitoring expert in EOS' volcano group. He tracks the region's volcanoes and their behaviour remotely before and after an eruption, such as the movement of magma and the low-frequency sounds radiated from the craters of volcanoes when they erupt.
Assistant Professor Caroline Bouvet de Maisonneuve from the same group has been retracing the past to search for evidence of large historic eruptions in Sumatra.
Having more records of colossal eruptions in the past will raise the accuracy of calculating the likelihood of a similar event in the future, said Prof Costa.
At least three other colossal eruptions have impacted Singapore in the past, the team said. The 1883 Krakatoa eruption, one of the most explosive in human history, also sent ash to Singapore.
Prof Taisne added: "What happened in the past informs what can happen in the future."
Meteorologist Mah King Kheong recalled that one of the first things the Meteorological Service Singapore (MSS) did after the ash fall in Singapore was to alert aircraft in the airspace it monitored to the volcanic ash.
MSS closely monitored the developments from the eruption, but back then, it was difficult to know how much ash would travel to Singapore as remote sensing systems were less developed.
But now, it has high-resolution satellite images and instruments to better monitor the spread of ash, said MSS.
MSS also has an atmospheric dispersion model to simulate how wind, turbulence and rain will shift volcanic ash.
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The eruption on June 15, 1991 - the world's largest in the past 100 years - sent ash to Singapore on the evening of June 17. The ash hung in the air here for three weeks before clearing, with some people reporting allergic reactions.
A plane flying from Changi to Osaka, Japan, was reportedly damaged after being caught in an ash cloud for 30 minutes.
Given the higher operating temperatures of jet engines today, ash particles can easily melt onto engine parts, affecting their function, and flights may have to be suspended should a similar eruption happen, said scientists.
Had there not been a typhoon in the Philippines at the same time, more ash would have travelled to Singapore and the impact here may have been more severe.
A 2015 paper put the chances of another Pinatubo-like eruption in South-east Asia occurring in any decade at 15 per cent.
Singapore is nestled close to the Pacific Ring of Fire, where Indonesia - which has more volcanoes than any other country - sits.
"Given that a typhoon with an eruption is a low-probability event, we would expect more ash if such an event were to happen again," said Assistant Professor Susanna Jenkins from the volcano group at NTU's Earth Observatory of Singapore (EOS).
The scientists aim to anticipate and forecast eruptions in South-east Asia so that the impact on infrastructure, the economy and health can be mitigated.
Said EOS volcano group leader Fidel Costa: "We cannot stop the eruptions, but we can prepare for them by using a wide range of monitoring tools, experiments and data from fieldwork."
Many car owners in several areas in Singapore discovered a layer of ash or dust settled on their cars. PHOTO: THE NEW PAPER
The scientists' research will look at how the country can better forecast eruptions of such a scale so that the authorities can be advised on mitigation measures.
For one thing, Prof Jenkins is looking to simulate how a major volcanic eruption, and a big earthquake or tsunami in South-east Asia will impact Singapore.
"So if it is an explosive eruption in Sumatra, for example, we would try to figure out when and how the ash would reach Singapore, and the effects on our airspace and supply routes," said Prof Jenkins.
Compared with 30 years ago, a more modernised Singapore is now widely reliant on technological equipment in areas such as transport, water treatment and power networks.
Even the ubiquitous air-conditioners may not be spared.
Fine ash from an eruption can infiltrate more deeply into electrical equipment, upending infrastructure and the aviation scene, said Prof Jenkins.
"Damp ash less than 3mm thick can cause short-circuiting on electrical networks, and ash particles can have acidic coatings that can cause corrosion or water-quality issues."
Studying the impact of eruptions on smart cities is a developing research area which needs post-eruption studies, experiments and calculations, she added.
For instance, said Prof Jenkins, a lab experiment could entail continuously running an air-conditioning unit exposed to airborne ash to find out at what point the filters clog and need replacing.
The eruption on June 15, 1991, sent ash to Singapore on the evening of June 17. PHOTO: U.S. GEOLOGICAL SURVEY (USGS)
"From experiments like this, we can have a better understanding of the actions needed, such as stockpiling more air-con filters, if such an event happens," she said.
For humans, exposure to ash may worsen health conditions such as asthma.
"Fine ash can penetrate deeper into the lungs. Unlike haze, volcanic ash is made up of sharp, crystalline glass and rock particles, so the impacts are not the same," said Prof Jenkins.
Associate Professor Benoit Taisne is the monitoring expert in EOS' volcano group. He tracks the region's volcanoes and their behaviour remotely before and after an eruption, such as the movement of magma and the low-frequency sounds radiated from the craters of volcanoes when they erupt.
Assistant Professor Caroline Bouvet de Maisonneuve from the same group has been retracing the past to search for evidence of large historic eruptions in Sumatra.
Having more records of colossal eruptions in the past will raise the accuracy of calculating the likelihood of a similar event in the future, said Prof Costa.
At least three other colossal eruptions have impacted Singapore in the past, the team said. The 1883 Krakatoa eruption, one of the most explosive in human history, also sent ash to Singapore.
Prof Taisne added: "What happened in the past informs what can happen in the future."
Meteorologist Mah King Kheong recalled that one of the first things the Meteorological Service Singapore (MSS) did after the ash fall in Singapore was to alert aircraft in the airspace it monitored to the volcanic ash.
MSS closely monitored the developments from the eruption, but back then, it was difficult to know how much ash would travel to Singapore as remote sensing systems were less developed.
But now, it has high-resolution satellite images and instruments to better monitor the spread of ash, said MSS.
MSS also has an atmospheric dispersion model to simulate how wind, turbulence and rain will shift volcanic ash.
More...