Sci-Tech Information:California Tests Natural Disaster Early Warning System
An early warning system for earthquakes, tsunamis and floods is being trialled in the US.
Scientists are using GPS technology and other sensors to detect the impending threat of natural disasters.
The network is installed in Southern California and has already helped scientists to alert emergency services to the risk of flash floods.
Yehuda Bock from the Scripps Institute of Oceanography said: "This can help to mitigate threats to public safety."
And added: "It means real-time information can be made available."
Ground motion
The minutes and even seconds before a natural disaster strikes are crucial.
Early warning systems can help emergency services to prepare and respond more effectively and can provide vital information for the public.
In California, researchers have been testing a prototype network for a range of hazards.
The system builds on existing networks of GPS stations, which use satellite technology to make very precise measurements of any ground movement.
On these, they have installed seismic sensors and other instruments that can track changes in weather conditions.
Dr Bock said: "By combining the data from the GPS with the data from these other sensors, we can measure displacements that occur during an earthquake or another event."
He added that the system could detect the tremors that appear seconds before a large earthquake strikes, and accurately assess its magnitude and whether it is likely to generate a tsunami.
The GPS sensors and the meteorological instruments also help the team to monitor the water vapour in the air.
Dr Angelyn Moore, from Nasa's Jet Propulsion Laboratory, said: "It might be surprising that we are using GPS to monitor weather hazards, but GPS is a weather instrument.
"Fundamentally, a GPS station is measuring the time it takes a signal to travel from the GPS satellites to the receiving stations on the ground, and that travel time is modified by the amount of moisture in the air.
"Whenever we measure the position of a GPS station, we are also measuring the amount of water vapour above it."
Through this, the team is able to track in real time how air moisture is changing and whether heavy rain is likely.
In the summer, the researchers used the system to forecast rainfall in San Diego.
Traditionally, some of this data comes from weather balloons.
"But there are only two sites at the southern border of California and these are about 150 miles apart. And the weather balloon launches are also infrequent: in San Diego it's only every 12 hours," said Dr Moore.
"In between those many hours between the weather balloon launches, we were able to use the GPS to monitor how the water vapour was changing."
With this real-time information, the team was able to issue flash flood alerts.
Dr Moore added: "This was verified - there were quite a few reports of flooding."
The sensing technology is being combined with communication advances to make sure the information is widely distributed, fast.
Dr Mark Jackson, from the National Oceanic and Atmospheric Administration's National Weather Service, said: "When a forecaster presses that button to issue that warning, it then goes to the police or fire person that's responsible for taking action to protect life and property almost instantaneously.
"We also have the public who now on their smartphones can receive warnings directly that say there is a warning in effect for your area."
The team said the technology was inexpensive, and systems like it could be rolled out around the world.
The findings were presented at the recent American Geophysical Union Fall Meeting in San Francisco.
GPS data could improve tsunami early warnings
Scientists say they have found a way to provide faster and more accurate early warning systems for tsunamis.
A German team says GPS satellite-based positioning could offer detailed information about the events within minutes of an earthquake occurring.
They believe the technology could have improved alerts issued when the devastating tsunami hit Japan in 2011.
The study is published in Natural Hazards and Earth Systems Sciences.
When an underwater earthquake happens, with the power to generate a tsunami, every second counts.
The shifting tectonic plates can generate giant walls of water that can travel towards land in minutes, giving little time to put evacuation plans into action.
Precise measurements
Existing early warning systems use seismological data, measuring the waves of energy that are generated as the earth moves and shakes.
But in the vital first stages of an earthquake, this is not always reliable.
Now a team from the GFZ German Research Centre for Geosciences says that satellite navigation technology could help.
GPS sensors placed around the coastlines of vulnerable countries could make highly precise measurements of how underwater tremors shift the ground.
Lead researcher Dr Andreas Hoechner explained: "In case of a subduction earthquake, one plate slips under another plate.
"It is measured in terms of relative displacement. This deformation is mostly above the source, but the coastal area is also deformed and this can be picked up by GPS."
He said that this information could be used to reconstruct the source of the earthquake and calculate its magnitude.
"Then you can then predict the tsunami and see how high a wave could be expected, with some accuracy."
This process would take a matter of minutes, which would allow alerts to be issued extremely quickly.
Disseminate warnings
In the case of the 2011 tsunami that killed 16,000 people in Japan, the technology could have made a significant difference.
Although the Japan Meteorological Agency issued a warning three minutes after the earthquake hit, it underestimated the scale of the event.
It suggested that the quake was 7.9 magnitude; it was actually 30 times more powerful.
By looking at data collected by GPS stations in Japan - which at the time were not used to measure earthquakes - the researchers calculated that this would have provided an accurate estimate of the magnitude within three minutes.
A number of countries are now installing GPS networks, including Chile and the US.
But Dr Hoechner said that as well as having accurate alert systems, well thought-out evacuation plans were also essential.
He said: "One point is to have the technology to realise what the earthquake is and where tsunami will be. But it is at least as important is to disseminate the warning.
"You have to have the infrastructure to transmit this information to the population, and the population has to be ready to know what to do."
Scientists are using GPS technology and other sensors to detect the impending threat of natural disasters.
The network is installed in Southern California and has already helped scientists to alert emergency services to the risk of flash floods.
Yehuda Bock from the Scripps Institute of Oceanography said: "This can help to mitigate threats to public safety."
And added: "It means real-time information can be made available."
Ground motion
The minutes and even seconds before a natural disaster strikes are crucial.
Early warning systems can help emergency services to prepare and respond more effectively and can provide vital information for the public.
In California, researchers have been testing a prototype network for a range of hazards.
The system builds on existing networks of GPS stations, which use satellite technology to make very precise measurements of any ground movement.
On these, they have installed seismic sensors and other instruments that can track changes in weather conditions.
Dr Bock said: "By combining the data from the GPS with the data from these other sensors, we can measure displacements that occur during an earthquake or another event."
He added that the system could detect the tremors that appear seconds before a large earthquake strikes, and accurately assess its magnitude and whether it is likely to generate a tsunami.
The GPS sensors and the meteorological instruments also help the team to monitor the water vapour in the air.
Dr Angelyn Moore, from Nasa's Jet Propulsion Laboratory, said: "It might be surprising that we are using GPS to monitor weather hazards, but GPS is a weather instrument.
"Fundamentally, a GPS station is measuring the time it takes a signal to travel from the GPS satellites to the receiving stations on the ground, and that travel time is modified by the amount of moisture in the air.
"Whenever we measure the position of a GPS station, we are also measuring the amount of water vapour above it."
Through this, the team is able to track in real time how air moisture is changing and whether heavy rain is likely.
In the summer, the researchers used the system to forecast rainfall in San Diego.
Traditionally, some of this data comes from weather balloons.
"But there are only two sites at the southern border of California and these are about 150 miles apart. And the weather balloon launches are also infrequent: in San Diego it's only every 12 hours," said Dr Moore.
"In between those many hours between the weather balloon launches, we were able to use the GPS to monitor how the water vapour was changing."
With this real-time information, the team was able to issue flash flood alerts.
Dr Moore added: "This was verified - there were quite a few reports of flooding."
The sensing technology is being combined with communication advances to make sure the information is widely distributed, fast.
Dr Mark Jackson, from the National Oceanic and Atmospheric Administration's National Weather Service, said: "When a forecaster presses that button to issue that warning, it then goes to the police or fire person that's responsible for taking action to protect life and property almost instantaneously.
"We also have the public who now on their smartphones can receive warnings directly that say there is a warning in effect for your area."
The team said the technology was inexpensive, and systems like it could be rolled out around the world.
The findings were presented at the recent American Geophysical Union Fall Meeting in San Francisco.
GPS data could improve tsunami early warnings
Scientists say they have found a way to provide faster and more accurate early warning systems for tsunamis.
A German team says GPS satellite-based positioning could offer detailed information about the events within minutes of an earthquake occurring.
They believe the technology could have improved alerts issued when the devastating tsunami hit Japan in 2011.
The study is published in Natural Hazards and Earth Systems Sciences.
When an underwater earthquake happens, with the power to generate a tsunami, every second counts.
The shifting tectonic plates can generate giant walls of water that can travel towards land in minutes, giving little time to put evacuation plans into action.
Precise measurements
Existing early warning systems use seismological data, measuring the waves of energy that are generated as the earth moves and shakes.
But in the vital first stages of an earthquake, this is not always reliable.
Now a team from the GFZ German Research Centre for Geosciences says that satellite navigation technology could help.
GPS sensors placed around the coastlines of vulnerable countries could make highly precise measurements of how underwater tremors shift the ground.
Lead researcher Dr Andreas Hoechner explained: "In case of a subduction earthquake, one plate slips under another plate.
"It is measured in terms of relative displacement. This deformation is mostly above the source, but the coastal area is also deformed and this can be picked up by GPS."
He said that this information could be used to reconstruct the source of the earthquake and calculate its magnitude.
"Then you can then predict the tsunami and see how high a wave could be expected, with some accuracy."
This process would take a matter of minutes, which would allow alerts to be issued extremely quickly.
Disseminate warnings
In the case of the 2011 tsunami that killed 16,000 people in Japan, the technology could have made a significant difference.
Although the Japan Meteorological Agency issued a warning three minutes after the earthquake hit, it underestimated the scale of the event.
It suggested that the quake was 7.9 magnitude; it was actually 30 times more powerful.
By looking at data collected by GPS stations in Japan - which at the time were not used to measure earthquakes - the researchers calculated that this would have provided an accurate estimate of the magnitude within three minutes.
A number of countries are now installing GPS networks, including Chile and the US.
But Dr Hoechner said that as well as having accurate alert systems, well thought-out evacuation plans were also essential.
He said: "One point is to have the technology to realise what the earthquake is and where tsunami will be. But it is at least as important is to disseminate the warning.
"You have to have the infrastructure to transmit this information to the population, and the population has to be ready to know what to do."
