Earth Observatory Blog

Submitted on 08 Jul 2020 by:

A commentary by Professor Benjamin Horton (Earth Observatory of Singapore) and Emeritus Professor Perter Horton (University of Sheffield), published online on 7 July 2020 in One Earth, looks at how the current COVID-19 pandemic and the climate crisis are signs of the unsustainability of human society and the decreasing resilience of our ailing planet.

Titled “COVID-19 and the Climate Emergency: Do Common Origins and Solutions Reside in the Global Agrifood System?”, the authors discuss whether both events have the same underlying causes and common solutions, and whether they might be rooted in a failing global agrifood system.

Citing declining...

Submitted on 02 Jul 2020 by:

On 22 December back in 2018, Indonesia’s Anak Krakatau volcano erupted. The collapse of its flank triggered a tsunami that killed more than 400 and injured at least 30,000 people. 

To understand how the events of that day unfolded with such catastrophic effect, an international research team led by Research Associate Anna Perttu from the Earth Observatory of Singapore (EOS) turned to the data collected from monitoring stations from all around the region, official reports, as well as satellite and visual observations.

Eruptions produce a wide range of signals. Humans can see and hear some of them only when close enough to the eruption. Monitoring instruments help fill the gap. Satellites can be used to image volcanic plumes that are too high or obstructed from an...

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 15 Jan 2020 by:

As at 5 pm on 15 January 2020, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported that Taal volcano’s eruption is still going on and retained the Alert Level for Taal at 4 (hazardous eruption imminent), where further eruptions are likely to occur in the coming hours or days.

The volcano continues to send dark grey steam-laden volcanic plumes up to 700 metres (m) in height drifting to the southwest of the volcano, and new cracks on the ground have been reported in several locations around the volcano. New observations indicate that the Main Crater Lake and parts...

Submitted on 14 Jan 2020 by:

As at 1 pm on 14 January 2020, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) retained the Alert Level for Taal volcano at 4 (hazardous eruption imminent), which means that further eruptions are likely in the coming hours or days.

The volcano continues to spew lava fountains up to 800 metres (m) in height from several craters, sending volcanic plumes to the southwest of the volcano. These lava fountains are emitted from the Main Crater and several vents on the northern flank of the volcano. In addition, new fissures or cracks were reported at several locations around the...

Submitted on 12 Jan 2020 by:

A continuous eruption from Philippines’ Taal volcano was observed on Sunday, 12 January 2020, at 5.30 pm (Singapore time). The powerful eruption sent an ash plume 10-15 kilometres (km) into the atmosphere and ashfall as far as Quezon city 65 km away, with volcanic lightning seen flickering continuously in the plume above the volcano. This prompted the Philippine Institute of Volcanology and Seismology (PHIVOLCS) to raise the alert level to Alert Level 4 (hazardous eruption imminent).

Alert Level 4 means that further eruptions are likely in the coming hours or days. The residents of Volcano Island, as well as communities within 14 km of...

Submitted on 12 Nov 2019 by:

Located high in the mountains are structures called “mountain huts” that provide refuge and safety to those who are in need of food and shelter. However, because of their location, these life-saving shelters are highly vulnerable to the projectiles from nearby erupting volcanoes.

In a study jointly conducted by scientists from the Earth Observatory of Singapore (EOS) and the University of Canterbury (UC), we looked at an eruption event in Japan to learn what we can about how to reduce the impacts of projectiles on roofs of building structures. Our findings were recently published on 7 November 2019 in the Journal of Volcanology and Geothermal Research.

We wanted to see...

Submitted on 05 Nov 2019 by:

Today is World Tsunami Awareness Day. It is a timely opportunity to create greater global awareness about tsunamis as a geological hazard. Before asking how we can stay safe (or safer) from tsunamis, we must first think about how we might improve on the resilience of our current and future infrastructure.

Let’s start by looking at what a tsunami is. A tsunami is a series of waves caused by an underwater earthquake, a volcanic eruption, a landslide, or meteorological processes (meteo-tsunamis). 

So why is SE Asia vulnerable to tsunami hazards? First of all, SE Asia lies in a complex tectonic setting that contains many fault systems and volcanoes. Coupled with a high population density and a tight network of infrastructure in coastal areas, one can imagine just how...

Submitted on 30 Sep 2019 by:

Just after 6pm on 28 September 2018 (Singapore time), a magnitude-7.5 earthquake struck central Sulawesi. The powerful quake generated a tsunami which, along with massive landslides, devastated Palu and the town of Donggala. These resulted in more than 4,000 people dead or missing.

In an economic loss assessment report issued by Indonesia's National Disaster Management Agency (BNPB), the Palu earthquake event caused more than S$1.5 million in damages.

Today, a year later, scientists from the Earth Observatory of Singapore (EOS) and their teams are ready to share some of their findings about this earthquake-tsunami event.

A Complex Rupture Sequence

Using a combination of seismic, geodetic, geologic, and written records, Assistant Professor Wei...

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...