Sunday, June 9

Earthquake forecasting – the weakest link

И сниться ему сон...
(а чё еще остается, если эта технология прогнозирования землетрясений нахуй никому не нужна?)

Earthquake forecasting is among the weakest links in geology as well as science in general. Humanity has always been literally caught napping whenever a tremor surfaces from the bowels of the planet.

This becomes even more worrisome when one notes that populations are growing, especially in the world's earthquake prone regions. Conservative estimates point out that earthquake fatalities around the world will reach at least 3.5 million in the 21st century - more than double the 1.5 million in the 20th century. The residents of Moore, Oklahoma, had a little more than 30 minutes before being struck by a twister. But, unlike the monster tornadoes that hit parts of the Midwest (and still claim lives), there is no such early warning system for earthquakes yet.

Now for some more chilling news:  It is common knowledge that quake prone regions exist in India, China and Iran, but they all run along the front regions of the Himalayan range as entire cities from Kathmandu to Delhi and even Chengdu are becoming particularly vulnerable to catastrophic quakes (or where death tolls go over 50,000).

"Rapid urbanization and emergence of mega cities in the Asia Pacific region have increased the risk posed by earthquakes and other natural disasters,'' said M. Shashidhar Reddy, Vice Chairman of the National Disaster Management Authority.

Indian geologists have warned of a "mega earthquake" that will strike the Himalayas this century, bringing a tragedy beyond imagination. Naba Kanta Borah from the National Geophysical Research Institute of India spoke about the fault that separates the Asian and Indian continental plates. Research shows that a segment of it dips downward by 15 degrees, and is steeper and further north than suggested by previous observations. This dip could rupture and cause an earthquake of magnitude 8 or more, Borah pointed out.

"There is huge geological activity going on in the Himalayas. They have been and will continue to remain a location for major earthquakes,'' Professor Sudhir K. Jain, an expert in earthquake engineering, explains.

Greater frequency
The increased frequency of the quakes in the region is also a result of the 2004 quake in Sumatra, Indonesia, which shook the entire planet, even causing it to wobble a bit from its axis. Apart from quakes in the northern regions, there is also increased seismic activity in Peninsular India as several tremors of magnitude 2 and 3 have been recorded in Andhra Pradesh in a short span of time.

Research by Singapore's Nanyang Technological University (NTU) has discovered that massive earthquakes between 8 and 8.5 magnitudes on the Richter scale have left clear ground scars in the central Himalayas. This ground-breaking discovery has huge implications for the area along the front of the Himalayan Mountains, recent NTU research showed.

"In an inter-connected world, disaster in one country could seriously impact many other countries. I would like to remind you about the impact of the flooding in Bangkok that resulted in disruption of supply of computer hardware the world over,'' Reddy added.

 China has made huge advances in earthquake predictions since the tragic magnitude 8 earthquake struck Wenchuan, Sichuan Province, in 2008, killing more than 80,000 people. China responded by establishing the Institute of Care-Life at Chengdu, where it has developed the world's largest earthquake early-warning system. This has been the prototype for similar stations across the country and has been successful in receiving early warnings for over 1,200 earthquakes.

When a magnitude 4.9 earthquake struck Yunnan on February 19 this year, residents in the area received warning messages on their cellphones, websites and microblogs before the quake reached the area. Again, when a magnitude 7 earthquake struck Lushan on April 20, an early-warning alert was flashed 28 seconds before the disaster. Studies point out that a 20-second alert can reduce casualties by 63 percent.

Different response
There were marked differences in the response to the Lushan earthquake and the Wenchuan earthquake five years earlier. Helicopters were quickly deployed in Lushan, where they used remote-sensing technology to locate victims and distribute aid.

Another major difference was the reaction time of online social networks, which played a critical role in relief efforts. Within one minute of the quake, users from the disaster area were posting messages for help on Weibo. On the same day, China's microblogging community set up earthquake relief channels.

China has also put in place an integrated monitoring system for data from ground-based instruments and foreign satellites. This will soon be followed by the country's first earthquake monitoring satellite, Zhangheng-1, to be launched in 2014. The satellite, named after the ancient Chinese scientist who invented the world's first seismograph, will focus on measuring various parameters of the ionosphere which is prone to the sensitivities of underlying earthquakes.

Now where do we go from here? The traditional approach has been shown to be increasingly inadequate.

Earthquake prediction and studies must include, apart from more updated geological data, seamless coordinated international information gathering and sharing of networks. While we may not ever be able to predict precisely when, where and with what magnitude particular earthquakes will strike, much can be gained from short-term "probabilistic" forecasting, which can give the odds that an earthquake above a certain size will occur within a given area and time. Still, these methods have their limitations, as was demonstrated when even the most up-to-date models was unable to predict Japan's deadly earthquake that killed 19,000 people on March 2011.
Global Times

No comments:

Post a Comment

You can write whatever you want, but technically, the precise mathematical-statistical forecast of earthquakes based on information about the behavior of wild and domestic animals, birds, fish, and individuals available from 1995, with the advent of social networking.

THE STRUCTURE OF INPUT BIG DATA: API applications to social networks