Earth Observatory Blog

Submitted on 15 Sep 2020 by:

When a volcano erupts in the darkness of night, or when it is blanketed by clouds, determining even the most basic information about the plume can be very difficult. Particularly for air safety, information like the time the eruption started, the height of the plume, and the eruption duration are crucial for determining what air spaces will be impacted.

Published on 15 September 2020, in the Journal of Volcanology and Geothermal Research, is a study I led that developed a new method to estimate plume heights. This method utilises the long-travelling low-frequency sound waves produced by the eruptions.

Infrasound, or sound that falls below 20 Hz, can travel thousands of kilometers and...

Submitted on 06 Aug 2020 by:

In conversation with Assistant Professor Aron Meltzner, Principal Investigator at the Earth Observatory of Singapore


1. How does the recent powerful magnitude-7.8 earthquake in Alaska remind us of similar hazards in Southeast Asia?

Last week, we saw a powerful earthquake off the coast of Alaska with a magnitude of 7.8 which had the potential to trigger a damaging tsunami, but fortunately this did not happen.

It occurred along a subduction zone where the Pacific Plate is subducting or slipping under the North American plate. The shaking that we know as an earthquake results from the sudden movement between these two plates, but that sudden movement also has the potential to lift up the seafloor, which in turns lifts the water above it, and that can...

Submitted on 21 May 2020 by:

Did you know that in the past six weeks six volcanoes in Indonesia erupted? These volcanoes are Semeru, Anak Krakatau, Merapi, Kerinci, Dukono, and Ibu. 

These recent eruptions are part of the usual volcanic bustle in Indonesia, impacting mostly the areas close to the volcanoes. While some of these activities were picked up all the way in Singapore, all were reported to aviation authorities.

Issuing Eruption Notifications

The Centre for Volcanology and Geological Hazards Mitigation (CVGHM), the monitoring agency for Indonesian volcanoes, issued a Volcano Observatory Notification for Aviation (VONA) on each eruption. The notification includes a summary of the volcanic activity, the...

Submitted on 18 Apr 2020 by:

A higher frequency of unusual weather conditions caused by global warming has melted the Greenland ice sheet by 600 billion tonnes, raising the world’s watermark by 1.5 milimetres – which is about 40 per cent of the total rise in sea level in 2019.

How will this affect Singapore? “Low-lying coastal cities and nations, like Singapore, should be very concerned about the extreme melting in Greenland and Antarctica,” said Professor Benjamin Horton, Chair of the Asian School of the Environment and a Principal Investigator at the Earth Observatory of Singapore. “If the ice...

Submitted on 02 Apr 2020 by:

Channel NewsAsia’s documentary titled “Carbon Conundrum” investigates how carbon emissions contribute to rising global temperatures, which lead to rising sea levels and extreme weather events. In the documentary aired on television (channel 106 on Starhub) on 31 March 2020, Assistant Professor Aron Meltzner and his team provided insights on how rising sea levels in the southeast Asian region could impact Singapore.

Using microatolls (circular colonies of coral) the team is able to track changes in the sea level. A study led by Asst. Prof Meltzner found that more than 6,000 years ago when there was no human-driven climate change, there were fluctuations of about 60 centimetres in sea levels in southeast Asia. He...

Submitted on 28 Sep 2019 by:

During the early evening of 28 September 2018, a magnitude-7.5 earthquake struck along the coast of northwestern Sulawesi, Indonesia. This region hosts a famous strike-slip fault system called the Palu-Koro Fault.

Even though this is one of the fastest slipping faults in the world, it has not produced many large earthquakes during historical times. The Palu-Koro Fault was therefore thought to have a high probability of a large and destructive earthquake, and so the occurrence of the 2018 quake in Sulawesi wasn’t very surprising.

However, the landsliding that was triggered by the earthquake turned out to be unexpectedly destructive. Soon after the earthquake, witnesses described entire villages south of Palu City sinking into mud and disappearing, and it was...

Submitted on 17 Sep 2019 by:

Many may still remember the powerful eruption of Mount Pinatubo in 1991. It was one of the largest eruptions in recent history, and sent volcanic ash even as far as Singapore, over 2,400 kilometres (km) away. 

But what many do not know is that the thin layer of volcanic ash that had settled across Singapore could have been more severe. Typhoon Yunya (also known as Typhoon Diding) had struck the Philippines almost at the same time as the Mount Pinatubo eruption.

Previously, scientists had not investigated how the typhoon had affected the amount of ash that fell on Singapore. However, preliminary modelling results carried out by scientists at the Earth Observatory of Singapore (EOS) and Asian...

Submitted on 24 Apr 2019 by:

When the time came for us to choose a place to house the EOS Dynamic Earth Games, the answer was a clear and obvious one – the Science Centre Singapore (SCS).

SCS has an impressive 40-year record of making science fun and accessible to the public. They successfully reach out to and engage more than one million visitors annually.

We, at the Earth Observatory of Singapore (EOS), know just how capable the SCS team is. We have worked with them over the years on various projects and launches (e.g. “Earth: Our Untamed Planet” exhibit currently in SCS, and the film screening of EOS documentary The Ratu River). Most recently, we spent the past six months working closely with SCS and acclaimed Californian science museum, The Exploratorium, on a new earth science exhibition...

Submitted on 17 Apr 2019 by:

When the Earth Observatory of Singapore (EOS) first decided to create educational materials about the earth sciences, all we knew then was that we wanted something extra fun, immersive, and highly interactive. The EOS Dynamic Earth Games that we have now were not yet in our minds.

The search for a team who could bring this to life for us was quite a task. That was until we met BOHO Interactive, a collective of artists and game designers from Australia.

During the planning phase, the BOHO team spent a good amount of time in EOS to learn about the different types of research being done by our scientists. They then shortlisted a few to build the games on. After developing several of these games, they tested the prototypes at different events with different audiences...

Submitted on 10 Apr 2019 by:

Did my last blog post about the Dynamic Earth Games (DEG) leave you hungry for more details about the games? Well, I hope to satisfy your curiosity in this second post.

The Earth Observatory of Singapore (EOS) collaborated with BOHO Interactive and the Science Centre Singapore to develop seven different games. These fall into three broad categories:

Volcanoes and Typhoons, Assessing Risk, and Evacuation.

Volcanoes and Typhoons

The Dynamic Earth Games explain the science behind natural hazards with a strong focus on geology and meteorology. While playing the games, you will learn some of the signs of an impending volcanic eruption and the tools that...