The Earth Observatory of Singapore conducts fundamental research on earthquakes, volcanic eruptions, tsunamis and climate change in and around Southeast Asia, toward safer and more sustainable societies.

Prof. Kerry Sieh
Director

The Earth Observatory came into even sharper focus throughout 2014, its sixth full year. We are a bit like a youngster growing through our late teens, realising more and more who we are and what we are becoming.

Our efforts to create the Asian School of the Environment leapt forward this year with the matriculation of our first cohort of undergraduate Environmental Earth System Science majors. These enthusiastic and hard-working students are a manifestation of our dedication to preparing future generations to understand and tackle humanity’s environmental, ecological and geohazard challenges.

The occurrence of the destructive Nepal earthquake in April 2015, just after the end of the year, drew attention to the importance of being a research institution that investigates geohazards before they strike. Professor Judith Hubbard’s group had been focusing attention on the earthquake geology of the Himalaya since her arrival at the Observatory in 2012, and Isaac Kerlow had nearly finished an educational film about that research and the Himalayan earthquake threat. The earthquake struck just as Paramesh Banerjee and his Technical Office team were on the Kathmandu airport runway, preparing to fly an airborne LiDAR mission that would enable Professor Paul Tapponnier’s group to expand their investigation of the great fault that causes most Himalayan earthquakes and threatens a large fraction of Earth’s human population. After the event, Professors Sylvain Barbot, Emma Hill and Shengji Wei joined in to help understand the source and nature of the earthquake and how it fits into the sequence of past and future great Himalayan earthquakes.

I’ve highlighted just two aspects of the Earth Observatory’s important work through FY2014. Without further ado, I invite you to explore more of our progress and accomplishments in this year’s Annual Report.

Professor Kerry Sieh
Director

Southeast Asia—one of the most active and complex regions on Earth.

Our researchers were busy this past year! Southeast Asia is one of the most complex and active regions on Earth, and a natural disaster could affect hundreds of millions of people. Yet there are still so many questions about geohazards and how they may happen.

Our scientists are working across several countries to fill the gap in knowledge in tectonics, volcanoes, and climate. Their work takes them from mountains in Nepal to coastlines in Vietnam. Some project highlights include monitoring tectonic activity in Sumatra, studying volcanoes in Philippines, and collecting haze samples in Singapore.

We’ve included a small sampling of the research happening at the Observatory, but there’s much more to explore!

Home to 600 million people, Southeast Asia is one of the most active and complex tectonic regions on Earth. EOS geoscientists are working their way toward a clearer understanding of tectonic movement across Southeast Asia, with the aim to better prepare its residents for the earthquake and tsunami risk they face. In 2014, much of the tectonic group’s research focused on Indonesia, which sits along the Pacific Ring of Fire, a hotbed of tectonic activity, but research also spanned the region including Nepal and Taiwan. Here are a few of the projects that our researchers focused on this past year.

Sumatran Fault Monitoring

Through the Sumatran Fault Monitoring Campaign GPS Project, Emma Hill and her collaborators are installing and monitoring a dense GPS network to track movement along the Sumatran Fault. This fault spans the ~1700-km length of Sumatra and passes close to many population centres, but so far is relatively poorly understood. This study may help to understand the potential size of earthquakes that can be generated by different segments of the fault.

Monitoring activities in Sumatra.

Aceh Cave

The 2004 tsunami was so devastating in part because the region hadn’t experienced one in more than 500 years. Charles Rubin and his collaborators are investigating a treasure trove of sediments from a cave in Aceh, northern Sumatra. The cave will provide the team with an 8,000-year history of tsunamis and earthquakes. And by combining archaeology with geology, Kerry Sieh and his team are gaining insight into how trade and settlement changed after a tsunami struck northern Sumatra in the 1300s.

Mentawai Gap

Many major earthquakes, including the 2004 Indian Ocean tsunami, have occurred along the Sunda megathrust, where the Indian Ocean crust is diving under the Sunda trench. A large section of the Sunda megathrust called the Mentawai Gap hasn’t had an earthquake in 200 years. Scientists expect that the accumulated stress in this gap will soon cause a giant earthquake as destructive as the 2004 earthquake. Paul Tapponnier and Satish Singh plan to set out on a deep-sea mapping expedition to assess tsunami risks along the Mentawai Gap.

On the aft of R/V Falkor, crew, scientists, and the Sea and Land Technology team deploy seismic reflection gear, which helps with data acquisition.

Meanwhile, Wei Shengji and team built 11 seismic sites around the gap to investigate how seismic waves travel through the fault. The Sumatran GPS Array measures deformation of the Earth's crust in the region, and we can use this to measure how the fault slips, before, during and after earthquakes.

Summary of the tectonic setting and earthquakes in Sumatra, in particular, the Mentawai seismic gap.

Nepal Earthquakes

The April 2015 earthquake in Nepal killed more than 9,000 people and left hundreds of thousands of people homeless. An earthquake of 8.3 magnitude or greater could kill more than half a million people. Using a high-tech seismic wave producer called the Envirovibe Minibuggy, Judith Hubbard and her researchers study how waves travel through rocks underneath the surface. Their goal is to create more accurate 3D models of faults to better understand and forecast the sizes and recurrence intervals of Himalayan earthquakes.

The Envirovibe minibuggy sends vibrations into the rock layers beneath the ground, gathering data that allows them to better visualise subsurface faults.

Research Fellow Anna Foster marks the exact location of the path that the minibuggy will take.

The Ratu River Expedition, a documentary film produced by Isaac Kerlow, features the research of Hubbard and the tectonics group.

South China Sea Tsunami

Southern China is one of the most densely populated and economically important regions in the world. It’s also a prime location for coastal hazards. In the early 1780s, a disastrous tsunami hit the southwestern Taiwan coast, killing more than 40,000 people. Through numerical modeling, Adam Switzer and his team analysed plausible causes of the 18th century tsunami, concluding that the most likely explanation was an underwater landslide.

Numerical models of the 18th century tsunami in southwestern Taiwan showed that an underwater landslide was most likely the cause.

Earthquake and Tsunami Physics

Besides studying specific regions in Asia, research projects are investigating general tectonic processes. Sylvain Barbot’s group is researching the role of water in the movement of Earth’s tectonic plates. By studying the deformation of the mantle after the great Wharton Basin earthquake in 2012, the team is able to estimate how much water is trapped in the oceanic upper mantle, an indication of how much water can be recycled in subduction zones.

Estimating trapped water will help scientists understand the role of water in plate movement.

Besides studying earthquake physics, the Observatory is also researching tsunami dynamics. Huang Zhenhua and his PhD student built a model coastline and observed how cliff angles affect tsunami flow. The outcome of this research will aid early warning systems and help scientists predict how a tsunami will come ashore.

Southeast Asia has some of the most active volcanoes on Earth. Using a multidisciplinary approach, the volcano group advances knowledge about the processes behind volcanic eruptions. Working in close collaboration with the Philippine Institute of Volcanology and Seismology (PHIVOLCS), the Indonesian Center for Volcanology and Geologic Hazard Mitigation (CVGHM), and the Rabaul Volcano Observatory (RVO), our volcanologists’ research is producing tools that will better estimate hazards. These highlighted projects show how the group is mitigating impact of volcanoes on residents living in close proximity and the far-reaching effects of volcanic ash.

One of Fidel Costa’s projects focuses on the EOS laboratory volcanoes: Mayon, in Philippines, and Gede, Indonesia. By closely studying the magma reservoirs and the conditions below these two active volcanoes, Costa and his team are learning what drives an eruption and improving volcano forecasts.

False colour images of volcanic crystals show different phases and portions of these crystals, giving clues as to what may happen in a volcano’s magma reservoir.

A cluster of orthopyroxene crystal with normal zoning, suggesting rapid growth and limited diffusion before eruption.

Benoit Taisne uses geophysical techniques such as seismicity and infrasound to understand the laboratory volcanoes and better anticipate their eruptions. He also works closely with various Singapore government agencies to improve the country’s resilience to volcanic ash. In 2014, Kelud erupted in Indonesia, creating a huge blast that destroyed most of the monitoring equipment nearby. But with remote seismic and infrasound sensors thousands of kilometers away, Benoit Taisne and his collaborators could monitor the Kelud eruption from a safe distance. Remote instruments may be a key element in early warning systems, especially when local monitoring equipment is destroyed.

Using remote seismic and infrasound sensors, scientists can monitor volcano eruptions from thousands of kilometres away.

Caroline Bouvet de Maisonneuve studies different volcanic eruptions to determine what conditions lead to the formation of a caldera. Trapped gas bubbles in magma can be the difference between an effusive volcano and a dangerously explosive caldera. She looks at the dynamics underneath volcanoes using a combination of methods such as petrology, geochemistry, textural analysis, and numerical modeling.

A schematic representation of magmatic processes that take place in a volcano’s conduit and reservoir.

WOVOdat

The volcano community needs a comprehensive database on world volcanic unrest that aims to improve eruption forecasts. WOVOdat is a database hosted and maintained by EOS that provides free access to critical volcanic information for the public, especially volcanologists and policy-makers.

Over the next century, global temperatures are expected to rise between 1 and 5 degrees Celsius. The important questions are: how will global climate change affect Southeast Asia, and how is human activity in Southeast Asia influencing climate change? Some highlights of our climate researchers’ projects shed light on these questions.

Indonesian Haze

Haze in Southeast Asia affects radiative balance and hydrological cycle at least in regional scale. In addition, outdoor haze killed one million people living in Southeast Asia and affected millions more in 2012. One of the biggest contributors of haze in Southeast Asia is peatland fire, which dominantly occurs in Indonesia. Despite its detrimental consequences to climate and human health, haze in this area has not been well studied. Mikinori Kuwata is filling that gap in knowledge. He burns Indonesian peat in his lab to analyse its atmospheric chemistry and how it interacts with water. Next, he’ll conduct observations in the field to study haze at its source in Indonesia. With the combination of experimental and observational data, Kuwata’s work will help us to understand how haze develops from peat fires and how it contributes to climate change and air pollution.

Peat found at Riau Province, Sumatra.

Past Climate Unlocks the Future

In addition to studying current atmospheric science, our researchers are investigating past climate patterns in Southeast Asia. The monsoon season is a dominant player in Southeast Asia’s climate. Too much or too little rain can spell disaster for the billions of people who depend on the monsoon for their livelihoods. Nathalie Goodkin’s team focuses on the 450-year-old monsoon record that can be discerned from corals in Vietnam. By investigating the coral’s chemistry, Goodkin can estimate the changing sea surface temperatures and rainfall in Asia.

Scientists extracting coral cores with a drill.

Koh Tieh Yong and his team are modeling present tropical climates and carrying out studies on tropical atmospheric dynamics, striving to address some of the important issues surrounding the effect of global warming on Southeast Asia’s climate. Wang Xianfeng analyses the chemistry of cave rocks in the Indo-Pacific to learn about what has driven rainfall for the past 100,000 years. Learning about climate variations in the past can help us answer questions about future climate change and better prepare ourselves for a warming world.

Numerical modeling of cold surge episodes in the South China Sea using the WRF model.

Research on the intersection of science and society plays an important role in achieving sustainable societies in Southeast Asia and beyond. The Art + Media Group explores new ways to raise awareness of natural hazards and communicate Earth science topics to the public through documentary films, art projects and interactive games. It also develops and produces a number of original and exploratory artworks and media projects inspired by Earth science, blurring the line between science and art. The Aftermath of Aid project seeks answers to questions about the impact of reconstruction offers practical solutions to improve policy, and makes research accessible to the public.

Art + Media Group

This year, Isaac Kerlow produced The Ratu River Expedition, a documentary film about earthquakes in Nepal. The 25-minute film features the research of scientist Judith Hubbard and the tectonics group on the Ratu River in southeast Nepal. The river