Tsunami warnings improving but still not ideal, expert says

Apr 12, 2012

(Phys.org) -- An Australian earthquake expert says it will be years before tsunami warnings can be made accurate enough to avoid unnecessary evacuations or alerts.

Dr Huilin Xing, who studies warnings systems at the University of Queensland says yesterday's 8.6 magnitude in Indonesia was a reminder of the system's limitations.

“While the tsunami system works well, it has its limitations and there can be many false alarms with large earthquakes. It's better than nothing but there's still a lot of work to do," said Dr Xing.

“Australia is years away from perfecting the system and how quickly that is done depends on the level of investment in research and development.”

After yesterday's earthquake and aftershock hit, alarms sounded to warn that a tsunami may have been generated. Thousands of people in Thailand and Indonesia fled coastal and low-lying areas for higher ground.

“The problem is, there are a lot of false alarms because not all large earthquakes will generate a tsunami,” said Dr Xing.

"Research shows us that an earthquake larger than magnitude 6.5 may generate a tsunami, but this is not directly or linearly related to size.

"Currently no single model can model the whole process of an earthquake and its triggered tsunami generation. This means we really need to look deeper to work out what kind of earthquake can generate tsunamis and how big the tsunami might be.”

Researchers needed to study the details of the earthquake, its “triggered sea floor motion” and interaction with water, he said.

Dr Xing there were fundamental differences in the types of earthquakes that suggested yesterday's Indonesian earthquake was not likely to cause a tsunami in the way the 2004 Boxing Day earthquake did.

Before yesterday's warning was cancelled, he noted that the earthquake (magnitude 8.6) and the following major aftershock (8.2) may have be located at a splitting boundary, indicating that the Indo-Australian Plate was splitting into two plates - the Indian plate and Australian plate.

“If so, the mechanism would be different from the previous major Sumatra earthquakes, such as the 9.1 magnitude in 2004, and the tsunami generated would not be so severe.”

Dr Xing said while the existing alerts were an improvement on the past, where no alert was available, it could be years before tsunami warnings could be made accurate enough to avoid unnecessary .

How long this will take depends on investment and 2004 Boxing Day was the unfortunate wake-up call the government needed to address the issue, Dr Xing said.

Explore further: Scientists obtain new data on the weather 10,000 years ago from sediments of a lake in Sierra Nevada

add to favorites email to friend print save as pdf

Related Stories

Tsunami not yet detected: expert

Apr 02, 2007

Although the Bureau of Metereology had issued a tsunami warning, at this stage a tsunami had not yet been detected, a University of Queensland geophysicist said this morning.

Nine dead in Indonesian earthquake

Sep 12, 2007

Officials reported at least nine people were killed and more than 100 injured after a strong earthquake and an aftershock struck the Indian Ocean Wednesday.

Cause of tsunami wave heights is studied

Aug 20, 2007

Irish-led scientists have found tsunami wave height is independent of earthquake magnitude and is instead linked to a rupture's vertical displacement.

Geological evidence for past earthquakes in Tokyo region

Jan 31, 2012

In 1923, a magnitude 7.9 earthquake devastated the Tokyo area, resulting in more than 100,000 deaths. About 200 years earlier, in 1703, a magnitude 8.2 earthquake struck the same region, causing more than 10,000 deaths.

Recommended for you

Giant garbage patches help redefine ocean boundaries

1 hour ago

The Great Pacific Garbage Patch is an area of environmental concern between Hawaii and California where the ocean surface is marred by scattered pieces of plastic, which outweigh plankton in that part of ...

New satellite maps out Napa Valley earthquake

3 hours ago

Scientists have used a new Earth-observation satellite called Sentinel-1A to map the ground movements caused by the earthquake that shook up California's wine-producing Napa Valley on 24 August 2014.

Rainfall monitoring with mobile phones

3 hours ago

Agriculture, water resource management, drought and flood warnings, etc.: rainfall monitoring is vital in many areas. But the observation networks remain insufficient. This is not the case for antennas for ...

Seismic hazards reassessed in the Andes

3 hours ago

Although being able to predict the date on which the next big earthquake will occur is still some way off becoming a reality, it is now possible to identify the areas where they will occur. IRD researchers ...

User comments : 0