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Emergency Alert Systems
This section of our technical library presents articles written about Emergency Alert Systems and Disaster Recovery definitions, terms and related information.
The 911Broadcast emergency notification and alert service can deliver a large number of phone calls using a network of phone systems employing digital phone lines simultaneously. Should a disaster such as a snow storm, wild fire or flood hit your area, 911Broadcast systems can alert your community quickly providing specific instructions if an evacuation is required.
This service is available using our emergency broadcasting systems. If a dangerous chemical spill occurs in your community, you can target specific areas to call. If a severe snow storm hits your area, your community can be notified of school closings or event cancellations.
Geologists: Computer simulation could predict, prevent forest fires
By Blaine P. Friedlander Jr.
As small earthquakes can be omens of larger ones and landslides can be precursors to avalanches, Cornell geologists have shown in a computer simulation that forest fires display the same natural behavior. Their findings, they believe, could be used to predict where large forest fires can occur -- and how to prevent them.
The researchers' findings appear in the Sept. 18 issue of the journal Science.
"What is surprising to me is that an event like a forest fire is so similar to other natural events," said Donald L. Turcotte, the M.M. Upson Professor of Engineering in the Department of Geology. "And humanity really plays a small role in these events."
Turcotte and his fellow researchers, Bruce D. Malamud, a Fulbright Scholar and visiting lecturer in geology, and Gleb Morein, a Cornell graduate student, built their computer model of forest fires and analyzed data sets from a number of forests and wildfires from around the world, including Yellowstone National Park.
Until 1972 Yellowstone had a policy of suppressing forest fires. This resulted in a large accumulation of dead trees, undergrowth and very old trees that became perfect tinder for fires. The researchers contend that the large Yellowstone fire of 1988, which burned 800,000 acres, could have been prevented if the policy of letting smaller fires burn to completion had been in place before 1972. The smaller fires would have eliminated the underbrush and dead wood earlier, thus reducing the likelihood of a large fire, they said.
In analyzing how forest fires start and propagate, the researchers found that the frequency distribution of small and medium fires can be used to assess the risk of larger fires, as small tremors are routinely used to assess the risk of larger earthquakes.
Turcotte explained that for natural occurrences there is a return period for events of different magnitudes. For example, meteorologists classify storms as five-year, 10-year, 50-year or 100-year. This is an example of behavior on the part of weather. "It's an interesting class of phenomena," he said. "Small landslides build up to large landslides, and I suppose this model can be applied to something like the stock market, which also shows a degree of self-organized critical behavior."
To model forest fires, the scientists developed a computer grid of a forest, then simulated dropping a match. If the match landed on a tree, the tree and its neighbors would burn. If the match landed on an area without trees, no fire ensued. Where the grid was packed with trees, a large fire ensued. The scientists said that the only previous application of this type of model was to study measles epidemics in isolated populations.
The scientists ran the model under different scenarios of forest density. Interestingly, for each scenario, the researchers found a range of small to large fires and many more small fires than larger ones, which correlates with the law of a fractal distribution. (Fractal distribution is the magnification of certain things, like the size of a fire, in proportion to their original size.)
Large forest fires are dominant when the forest is densely populated. This was demonstrated by the researchers when the computer grid was filled with trees: The fires spanned the grid. This is what happened in Yellowstone National Park in 1988. The scientists said that forest-fire professionals now recognize that the best way to prevent the largest fires is to allow the small and medium fires to burn.
The scientists found that actual forest fires have fractal distributions over many orders of magnitude. However, the environmental- and human-related variables that affect the size of wildfires are many, including the proximity and type of combustible materials, weather conditions and fire-fighting efforts to extinguish certain fires, the researchers said.
"Despite these complexities, the prediction capability of the forest fire model appears to be robust," said Turcotte.
The Science article is titled "Forest Fires: An Example of Self-Organized Critical Behavior." Funding for the research was provided by a grant from the National Aeronautics and Space Administration (NASA).
Our Service Is Activated Online Or By Phone
The 911 emergency broadcast service is easy to install and use. We help you collect community call lists and organize them in a fashion that best fits your emergency broadcast requirements. When an emergency arises, you simply record your emergency message offline or use our toll free phone service to record your message.
Next identify your call recipients using a simple list manager or a graphical map display and send us your phone numbers via the internet. You can also identify pre-defined lists to call using simple touchphone responses on our toll free service. We do the rest.
Unlike some systems that are limited by the number of lines available to perform this emergency dialing, our service is provided to you using a network of thousands of phone lines that can deliver your emergency messages much faster.
Our emergency notification system delivers messages to individuals or answering machines and can even allow the call recipient to make touchphone selections. This may be critical if your response center requires a positive acknowledgement from the call recipient.
Purchase Or Outsource?
This is a question that communities should carefully consider. A purchased system gives you more control, but requires sufficient phone lines, equipment and on site technical knowledge to keep your system operational. The larger your community, the greater capital expense is required to broadcast your emergency messages in a timely fashion. If your message broadcasting system is used for more than just emergencies, it is easier to justify a purchase over contracted service. After all, emergency phone broadcasting is something you hope you never need to use.
Contracting your emergency broadcasting service requires less up front capital and can provide a faster emergency broadcast response if your provider has the resources available. Other than a monthly subscription fee, you only pay for the emergency broadcast as it occurs. System redundancy is available as well as centralized and experienced technical assistance.
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