Earth Observatory Blog

Submitted on 24 Nov 2020 by:

Earthquakes, typhoons, volcanic eruptions and floods are some of the hazards we live with. But we can lessen the impacts of these hazards on our lives and livelihoods by following Disaster Risk Reduction (DRR) strategies. These strategies help societies prepare and respond to hazards, and therefore reduce the associated risks. DRR can happen at all levels, from individual actions to international agreements.

Disaster risk was the focal point of the APRU-IRIDeS Multi-Hazards Virtual Summer School 2020. Held over three days on 15, 22, and 22 July 2020, the summer school was organised by the Association of Pacific Rim Universities (APRU) and the International Research Institute of Disaster Science (IRIDeS).

Usually held at Tohoku University and involving lectures and...

Submitted on 19 Nov 2020 by:

Typhoon Goni (Rolly in the Philippines) caused more than 20 fatalities in the Philippines earlier this month. Just a few days later, Typhoon Vamco (Ulysses) struck the Philippines again, then Vietnam on the other side of the South China Sea. “It is fairly common for more than one storm to occur in an ocean basin at the same time”, said Associate Professor Adam Switzer, a Principal Investigator at the Earth Observatory of Singapore. “Since typhoon season in Asia runs into the new year, there is unfortunately a real chance of further storms in the region before the end of 2020”, Assoc Prof Switzer added.

Typhoons form under specific sets of conditions between the ocean and the atmosphere. For example, warm sea...

Submitted on 23 Sep 2020 by:

In conversation with Fangyi Tan, PhD student, Sea Level Research team at the Earth Observatory of Singapore


1. Will melting ice sheets in such quantities pose a threat to Southeast Asia in the future? 

recent study found that the Earth has lost a staggering 28 trillion tonnes of ice between 1994 and 2017. The scientists commented in a related news article that the melting of glaciers and ice sheets could cause sea levels to rise by as much as a metre by the end of this century.

One metre may not sound like a lot...

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 Jul 2020 by:

Sea-level rise is a hot topic today in Singapore. Prime Minister Lee Hsien Loong, in his 2019 National Day Rally Speech, spoke at length about how vulnerable our island state is to 21st-century projections. However, sea-level rise is not a recent phenomenon and neither are the extreme impacts it has had on Singapore’s landscape.

Here’s another interesting fact – Singapore was not always an island. During past ‘ice ages’ where most of the world’s water was locked at the Poles, the sea was found hundreds of kilometres further away from where it is today. The clues pointing to what happened to Singapore thousands of years ago as a result of sea-level changes can be found right under our feet.

A team from NTU’s Earth Observatory of Singapore (EOS), the British...

Submitted on 14 Jul 2020 by:

In conversation with Professor Benjamin Horton, Director of the Earth Observatory of Singapore 


1. How might a breach of the 1.5°C Paris Agreement in the next five years impact Southeast (SE) Asia?

This week a new report released by the World Meteorological Organization (WMO) shows there is a 1 in 5 chance annual global temperatures will be at least 1.5°C warmer than in pre-industrial times in the next 5 years. This is very worrying to the planet. From the Paris Agreement, we needed to keep our temperatures below a 2°C temperature rise before the end of this century. The importance of the Paris Agreement cannot be understated.

If we go beyond the Paris Agreement we will cause a destabilisation of the Greenland and Antarctica ice sheets, it will include...

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 15 Jun 2020 by:

The first results from Singapore’s first island-wide seismic survey unravel some important features of Singapore’s underground.

In March of last year, a team at the Earth Observatory of Singapore (EOS) recorded the ground movements of Singapore using 88 seismometers placed in locations such as schools, parks and weather stations.

We collected a vast quantity of fascinating data using distant earthquakes to image Singapore’s subsurface, and our first set of results were recently published in the journal Geophysical Research Letters.

Seismologists use a technique called receiver functions to look at boundaries between different rocks...