- How to reach a passenger on a moving train (like the hundreds who perished unwarned in Pereliya on 26th December 2004); and
- How to reach visitors at the rest stop on the beach at Yala (where dozens perished from the tsunami as well).
Myanmar’s disaster: SMS or cell broadcasting for early warning?
May 19, 2008 (LBO) - The loss of tens of thousands of lives in Burma (Myanmar) in our region’s largest human disaster since the 2004 tsunami reminds us once again of the urgency of solving the problem of the last mile of the early-warning chain.
I no longer call these events “natural” because, for the most part, the deaths are caused by human action/inaction, not by the natural hazard per se.
This column is dedicated to the needlessly dead in Burma. I normally write about hard choices that do not allow one to keep the cake and eat it. But this column is an exception.
The answer to effective early warning is short message service (SMS) also known as texting AND cell broadcasting, deployed in parallel for different purposes.
The information of a powerful cyclone heading for the Irrawaddy delta was communicated well in time to the Myanmar authorities; the problem was that the warning did not complete the last mile to the citizens; the problem was that evacuation did not occur. The final few links of the chain were weak to non-existent. The chain broke at the weakest link, as chains do. People died, needlessly.
Citizens must be made aware through public warning. But more important is that first responders (persons in authority at the ground level, such as the Police or village leaders) must be communicated with BEFORE the public warning, so that they can organize orderly evacuations and conduct localized warning. Of necessity, media must be communicated with BEFORE the issuance of the public warning because they are the primary medium of public warning.
There are several technical solutions for communicating to first responders and the media: addressable satellite radio, dedicated radio systems separate from public networks, and SMS. Because redundancy is highly valued in the field of disaster risk reduction, there is no reason to place all eggs in one basket.
In the aftermath of the 2004 tsunami, LIRNEasia tested several of these technologies with a closed-user group of 32 Sarvodaya tsunami-affected villages .
In this column, I will discuss only one of these options, SMS to a closed-user group of media/first responders, and a very good public-warning technology that has not yet been fully tested in Sri Lanka, cell broadcasting.
SMS to first responders and the media
Analysis of the false warning and evacuation of the coastal areas of Sri Lanka on 12th September 2007 showed that the evacuation order was issued by political authorities without the full involvement of scientific personnel. One reason the scientific personnel could not play their rightful role in assessing the evidence was the lack of proper protocols and procedures within the various organizations.
The Department of Meteorology is designated the authority for receiving tsunami hazard information from international and regional sources, in addition to their role as the nodal point for cyclone hazard information. The Disaster Management Center (DMC) is designated as the authority for issuing public warning.
Therefore, the media should have been talking to the DMC and the Met Department should have been focused on interpreting the incoming hazard information and advising the DMC and the political authorities to the best of their scientific knowledge.
What happened was that the phones at the Met Department were fully occupied by journalists calling to get reliable information, preferably from the mouth of the head of the department himself. There was no time for scientific assessment of the incoming facts, including data from models showing landfall after three-four hours at least . The evacuation order was issued from Temple Trees.
One lesson to be learned from this mistake is that we must develop procedures to insulate the key scientific decision-makers from ad hoc news gathering at such critical times. They must be allowed to do their primary tasks in peace. The media must be provided with fast, reliable and trustworthy information that is not subject to misinterpretation (as would hurried phone calls).
The solution is a reliable, one-touch method of quickly alerting the news media, complemented by an updated website that will provide greater detail. The one-touch method has been developed and is now available for any government agency in Sri Lanka or elsewhere to use, subject to a few tweaks and tests that will be completed in a couple of weeks.
The SMS module that has been designed is part of the Sahana disaster management software suite , developed by Sri Lankan engineers and deployed throughout the world, from New York City to the Philippines. It allows government authorities to send a text message based on a pre-planned template to a group ranging from a handful to several hundred persons with one command. The numbers to which the message is sent are located in the Sahana database and can be used in the disaster relief and recovery phases as well.
One group of recipients can be pre-registered journalists; another can be the government first responders at the district level; another can be key officials and political authorities. They can be sent the same message or tailored messages.
As long as the button is pressed before word of the oncoming natural hazard reaches the public, it will be effective in quickly reaching the recipients. The system is not without weaknesses, but it is extremely low-cost and it is ready for deployment in weeks.
The principal weakness is inherent in SMS, which is a point-to-point communication technology (requiring switching to send messages to specific addresses). If too many SMS messages are sent that the same time (as happens after a bomb, for example), the network gets congested and the messages go through, but slowly. It took four hours for my SMS messages to get through on 26th December 2004.
It is like what would happen to the roads if all the motor vehicles in an area converge on them at the same time. The traffic would slow, if not stop altogether.
Theoretically, it is possible to build networks capable of carrying this kind of unusual-peak traffic, as it is possible to build roads that could carry all the vehicles in a region at the same time. Both would be horrendously wasteful, because the excess capacity would lie unused most of the time and every user will have to bear the extremely high costs. Of necessity, networks are designed to carry normal traffic, not extremely unusual peak loads.
Therefore, we have to take as given that all point-to-point networks (as opposed to broadcast or one-to-many networks) are prone to congestion. They are, therefore, unsuitable for public warning and coordination in the immediate aftermath of a disaster.
SMS is a point-to-point technology to which this conclusion applies. It is based on packet transmission and is therefore a little more robust that normal circuit-switched voice telephony, but it is nevertheless unsuited for public warning and immediate post-disaster coordination.
SMS is also limited in the number of characters it can carry in one message: 140 characters. This problem can be alleviated by using workarounds such as preset templates embedded in the handsets of the recipients that are filled by the SMS. The Sahana solution does not include this feature at this time, but it can accommodate such improvements.
The short-term solution for journalists is to combine the SMS with another technology, using the concept of “complementary redundancy” developed during the LIRNEasia study. This means that the simplicity of the group SMS transmission is used to alert the recipient; the greater detail is provided through a website, which should be accessible from any newsroom (subject, of course, to it being designed to accommodate a large number of simultaneous hits, but this is not hard).
The addressable satellite radio solution field-tested for the first time in Sri Lanka by LIRNEasia can also serve to achieve complementary redundancy. However, the fixed costs of this solution are such that its deployment requires government involvement at this time.
In sum, the simple SMS module designed as part of the Sahana suite is a simple, robust solution that can be deployed in weeks. It reaches the ordinary mobile phone that has today achieved the status of organic extension of the sense of hearing. Like vision-impaired people (like me) always carry their glasses, many of us always carry our mobiles.
Cell broadcasting
In discussing the question of public warning at a meeting of telecom operators and senior disaster managers convened by the Ministry of Disaster Management and Human Rights in 2007, I challenged the operators to solve two problems. If they were solved, the rest would be easy. The two problems were: