No-one has escaped the traumatic images of the earthquake and tsunami destruction in Japan, the latest in a string of natural disasters to hit the Asia Pacific region in recent months. Thousands have been killed and injured so far, but the loss of life has likely been limited by three vital early warning technologies: a new earthquake alert system; an ocean-based tsunami warning system and a mobile phone disaster warning service.
Japan has the world’s most advanced earthquake early-warning system, with more than 1,000 seismographs scattered over the country. Collectively, they detect tremors and allow for brief advance warnings not only to vulnerable sectors like railroads and utilities – so they can slow down high-speed trains and shut off gas lines – but also to the public.
Tsunami warnings take longer to generate. A string of detection buoys in the Pacific Ocean detected the tsunami that resulted from the earthquake, sending warnings of possible catastrophe to many different nations. The Japanese government issued a local tsunami warning three minutes after the quake struck, and the Pacific Tsunami Warning Center, issued its regional warning in nine minutes. These longer response times are a reflection of heavier computation requirements in determining whether the quake happened in an ocean basin, the likely deformation of the ocean floor, and what kind of motion was created by the quake.
Fortunately, while tsunamis are fast, they are not as fast-moving as the earthquakes themselves. Tsunamis travel as fast as jet aircraft in deep water, where they are spread over a far deeper water column and make for smaller and very gradual waves at the surface. They slow down and produce higher waves in shallower water. Residents of the hardest-hit areas in Japan likely only had fifteen minutes warning.
It’s that fifteen minutes that may have contributed to the saving of many thousands of lives. Subscribers of NTT Docomo, Japan’s dominant mobile phone operator, that opted for having alerts about earthquakes pushed directly to their phones would have had plenty of warning about the earthquake, but not a tsunami warning. The technology that makes this possible, the Area Mail Disaster Information Service, is designed to deliver detailed alerts as quickly as possible to compatible handsets, but only warns of earthquakes.
However, as MIT’s ‘Technology Review’ reports, little-known technology known as Cell Broadcast, or SMS-CB, a GSM feature for that has been around for many years, is barely utilized and could be major life-saver in future. It’s totally unlike traditional, point-to-point SMS, in that it can be broadcast directly from cell towers to every phone in range and does not use more bandwidth when sent to more users. In this way it’s just like a over-the-air television or radio, where bandwidth requirements do not increase as more users receive a signal. I can remember the ‘Cell Broadcast’ option on a very early Nokia mobile phone that could be set on or off, but never remembers ever receiving any messages. The function is reportedly used more on European networks but its most value may only now be coming to light.
Cell Broadcast allows messages (up to 15 pages of up to 93 characters) to be broadcast to all mobile handsets from those on a single cell to the entire network. Linked to the fact that most people now carry mobile phones with them at all times it becomes the most powerful means of mass-communication available. TV and radio warnings only work if people are using those mediums, but messages to mobile devices are focussed, fast and effective.
Maybe we, as an industry, should make this feature more readily available, particularly to emergency services, and educate customers how to set it up, where necessary, and how to respond should an emergency broadcast message be received. We are now seeing mass evacuations from areas at risk from radioactive fallout in Japan. How much easier and more effective would this exercise have been if unassuming Cell Broadcast was used?