Radio is best for disaster warning; remotely activable satellite radio is very best

Posted on January 28, 2007  /  19 Comments

Support for the HazInfo project’s position that radio, which allows for point-to-multipoint congestion-free transmission of warnings is the optimal technology. The LIRNEasia and WorldSpace developed solution, which allows for remote activation of radios is even superior to what is described in this article.

However, the article points out that a lot of institutional factors need to be addressed for the warning to be effective, an issue we are grappling with in the Sri Lanka pilot.

Air Support – New York Times

Consider, for instance, the basic question of where you would turn for information if disaster struck your hometown. The Internet puts up-to-the-minute information at your fingertips, but not if you can’t turn on your computer or your local network is down. Mobile phones allow for voice conversations and text messaging, but not when the system is jammed from overuse. Cable television offers hundreds of channels, but not one of them works when the power is out. Radio, when accessed by battery-powered receivers, provides the optimum combination of reliability and accessibility — but not if local stations have no one in the studios to report the news.


  1. Hi Rohan,

    Does the remote activation also control the volume level? I wonder how the system would work if the radio set’s volume was set low or at zero.

    Also found this fascinating –


  2. As of now the remote activation does not control the volume. It only switched to the audio channel that carries the hazard-related information. While training to use the system it is emphasized to leave the volume at a reasonable level whether or not the radio is being used for listening to one of the normally available audio channel.

    However, the system has the optional provision of triggering an external siren at the onset of the alert and the sound level of the siren is not controlled by the volume knob of the radio. Once alerted by the siren any one with access to the radio can further increase the volume and the radio would play only the disaster audio channel as that switchover has been accomplished remotely.

  3. That was an informed response from the VP (Technical) at WorldSpace.

    For those who are interested, the equipment is available at Samana Teta, the Sarvodaya Community Disaster Management Center at Moratuwa, Sri Lanka. Arrangements can be made for a demo.

  4. I like very much the fall-back option of an alarm triggered remotely irrespective of the volume level , and submit that if cost / hardware are not limiting factors, that it is made a standard feature instead of an optional one.

    Thanks for the clarification.


  5. Well. Nice to see its going forward. The radio alert idea is very practically.

  6. Remotely activatable radio has potential. Sounds like it might be costly to deploy though, unless there is a way to work with existing radio sets.

    How much has the potential for working with local media institutions and SMS technology been investigated? A first level of key contacts in 20-40 media stations can be alerted by SMS. A second round of 1000-3000 people can also be alerted by SMS. The first SMS can be sent in 20 seconds and the second round in 3-6 minutes with current technology.

    Alerting 1000 to 3000 key people who are asked to take responsibility for their villages also ensures some order amidst possible chaos.

    The speed of delivery by SMS is also improving, and there may be potential to send much large number say 5000 to 20000 in a few minutes on the different networks as they probably can deal with more bulk within their networks.

    The above system can be implemented even tomorrow, and might be good to have it up and running parallely with other systems. Other systems such as remotely activatable radio, satellite warning systems etc can be rolled out in the mean time.

    I believe there is no problem in multiple warning messages being sent, its just a matter of how fast and how widely spread they are that matters. After 15-30 minutes the media will take over and everyone will try to listen to radio, or watch TV to find out what is happening.

  7. All the investigations have been done: please see:

    Project documents available at:

    Use the relevant terms in our search box or just use google. You will see all the work that has been done.

    There is no need to reinvent the wheel.

  8. Many thanks, no doubt all these options were explored. Sorry but I am new to this website, so haven’t been following the threads. So is local media part of the equation now? and if so at which point. Being part of the media I would like to know its going to work and how I can get involved.

    Also has the SMS idea bean implemented? If the SMS alerts to media has been implemented, I would like to know how I can get on the list as a representative of a media organization.

    Sorry but I couldn’t find the answers in the posts, would be very grateful for a response thanks.

  9. The SMS idea has been explored in great detail (use SMS as a search term on our blog). It’s fundamentally flawed because SMS is less reliable than voice, even in normal times.

    I am sorry, but I do not have the time to go over the material that has been written up and is available on the website: Samarajiva, R. (2006) Mobilizing information and communications technologies for effective disaster warning: Lessons from the 2004 tsunami, New Media and Society (7(6); 731-47. Prepublication version:

  10. Thanks, but my question was to what extent media has been incorporated into the system for disaster warnings.

    What are the current methods in place to alert media?

    How many are on that list?

    How do others get on it?


  11. Please call the Disaster Warning Center headed by Major General Hettiarchchi to get the specific information you want.

  12. Thanks, I guess what you mean is that its not within the purview of your work right now. That you are not aware of any major effort to incorporate the media into disaster warning systems. That there is no simple campaign out there, like an email list from the Pacific Tsunami Warning Centre, to mention of. And that this Disaster Warning Center doesn’t have a website with clear simple information for those who want to know.

    If I seem triggered in these posts Professor, I apologise. I am one of your biggest fans from the time you were at TRC. This is just a request in general to anyone who might read this post to put down what you know in relation to media and disaster warnings in Sri Lanka.

    I believe media is probably the most effective warning tool, next to remotely activatable radio in every home (which I don’t see happening for a while). A few messages to media institutions, maybe followed up by a short email with details, will get the message out to the furthest corners of the island in 10-15 minutes. It may not be perfect, but I will prefer to see it in place today, rather than other measures in a few months time. This coupled with alerts and other systems is fine (if cell broadcast alerts are possible then great, cell broadcasts used by Dialog are silent at the moment aren’t they?)

    Anyone who hears a rumor will switch on their radio or TV to find out what is happening to get instructions anyway. Any disaster warning systems that don’t take media comprehensively into account is going to be a bit silly, since everyone turns to the media. If not, media will be floundering with second-hand and second-best information after a disaster happens, which could be very counter productive.

    In a situation where the authorities know what is happening, but the media doesn’t, they will start their own stories which could very well confuse people. I believe, something similar happened after the tsunami with TV stations starting their own relief efforts which sometimes duplicated what the government was doing. Including the media is an absolute must, so that they know as well as anyone else, what is going on.

    Maybe its not a fail safe solution, but the more systems out there, the better it is.

    If anyone has any concerns about the media carrying the wrong message, or causing a panic, say so, and lets start a discussion, I personally don’t think there are any such risks and the benefits far outweigh them.

  13. The questions are significant and there is discussion in depth around them. There are very solid arguments against giving warning information to media unless properly verified, etc. (not that I agree with it in toto, but I am simply stating there are people of goodwill and knowledge who hold these positions for good reason). If you are serious, you will take the time to investigate these larger debates.

    I wrote about this in very simple form in my first LBO column in Feb 2005, it should still be available. Lives are at stake here. Simply having opinions may not be enough in these circumstances. There is a place for investigation, evidence and trade-offs. This website was such a place (and to some extent, still is). But I do not have the time to repeat things that have been discussed in detail on this same site.

    If you simply want information on how to get on a list for warnings (if such a list exists), this is not the right place. I pointed you to it.

  14. Thanks Professor for your comments, hope there are others who are also willing to post on this subject here and hopefully enlighten me and others who are interested in the current state of play of the role of media in disaster warnings.

    If this isn’t the correct thread to post on this subject I apologise. If I can be pointed to threads discussing media, I would greatly appreciate it.

    Being in news for several years, this is my area of expertise, so permit me to post some comments here. While understanding media from the outside might not always be easy, the net impact of media is clear.

    What the public – a population of 20 million people – is going to listen to, take instructions from and be influenced by is TV, radio, newspapers, internet news etc.
    The messages of departments, institutes or companies will not reach people unless carried by media outlets. So a comprehensive study of how to include media in pre- and post- disaster scenarios is essential, and no doubt being looked into.

    Media has evolved for the very purpose of providing information to the public. But I have been a bit worried not to see an active engagement and discussion of the role of media in disaster warnings with media institutions. Maybe its happened, but then those findings have to be presented to the 100s or 1000s of media people out there so they know the state of play, are in the loop, and ready for the next disaster. Or it could be chaos the next time.

    Why didn’t the boxing day warning reach people even though it was available? Because it didn’t reach news stations, the people who had the information didn’t know what to do with it and how to get it to the people living on the coast.

    In my opinion, the tsunami tragedy could have been avoided or mitigated if tsunami warning centres that had information contacted major media outlets such as BBC, CNN, Reuters and conveyed what they knew. For this fact alone, I am surprised there wasn’t a major investigation to understand who was responsible for not going public with the information.

    The deaths were preventable, and the media wasn’t contacted quickly enough. It’s as simple as that. It was mass murder on a massive scale and people have been hauled to court and jailed for less. No doubt the people who had the information didn’t know how to work with media, didn’t have the skill set required to communicate with media and therefore sat on it.

    Dealing with media is a specialized job and needs to be recognized as such.
    To put it simply, to know what you can and can’t tell a reporter, and know what you can tell a reporter as background information requires experience. Maybe because it happened in Asia, Western earthquake monitoring institutions weren’t responsible to anyone.

    I am encouraged now by the Pacific Tsunami Warning Centre that seems to send a quick email with details of what they know and a paragraph talking about the possible threats. Sri Lanka can follow the same model, when it comes to reaching the media, and need not look for much greater sophistication. SMS or cell broadcast technology is already available for alerts and would be ideal to alert reporters to the email or web update.

    I believe the PTWC uses mostly pre-written messages, which are thoroughly studied before hand and carefully sent with the appropriate level of information at the appropriate time.

    This needs to be done by an authority like the Disaster Warning Centre or Tsunami Warning Centre in Sri Lanka. Any responsible media institution will take those words verbatim and publish them, so there is no need to worry about a corruption of facts.
    A corruption will happen only if there isn’t enough information available to the news casters, or the news agency can’t reach the relevant authority.

    I will repeat that point, because around it hinges the whole issue of reliable dissemination of information via media and the only point I am trying to make here.

    In a breaking news environment, reporters need as much information, ideally from as many sources as possible, or 1 reliable source or authority, to get a clear picture to be broadcasted to their audiences. When this happens they are able to transmit this to the public.

    But in a scenario where people who know the facts are not reachable by telephone, when there are no spokespersons for official comments, when there are no statements coming out immediately (such as emails or web statements) reporters have to rely on other sources like people who call in, friends, personal contacts and other random sources. Sometimes this could be just 1 or 2 callers. In such situations, you can no doubt imagine, the news broadcasts can be way off the mark.

    The role of informing the media will have to be handled by some responsible authority.
    Giving media unverified news is not what I am talking about here. This authority needs to very quickly prepare short and longer statements presenting what they know and the level of threat. These statements then need to reach people via TV, radio, cellphones, satellite phones, sirens, fax etc.

    These statements will have to be prepared whether its for media or not, and nut paragraphs can be pre-written. Thats a job for experts who need to simulate scenarios and have an idea of what may happen.

    For media needs, this authority will need to handle 20-50 phone calls during a crisis or have systems in place to push out information via websites and email in trilingual format. Ideally all three.

    It is essential to expect this and to prepare for it as it will undoubtedly happen.
    Meeting this huge need for information is the best way to ensure public welfare. This system will only go wrong if news stations A and B don’t get any statement emailed to them, and they get stuck trying to find out what is happening and then broadcast second-hand information.

    To digress from my comment, there is now an information democracy. No news outlet will want to broadcast wrong information for they know they will be punished by their audience and those in authority alike. It’s in everyone’s interests to get it right.

    If those who have engaged with the media have had bad experiences, well thats what a developing economy is all about, isn’t it? I believe, development economics is not about ignoring underperforming sectors, but engaging, supporting and boosting them.

    Disasters for the most part are straight-forward reporting work, whereas a new economic policy on banking, for instance, will require specialized journalists to understand and report them.

    To wind this long comment down, on the information needs in a post-disaster scenario, the following questions might come in chronologically:

    1) What happened
    2) Number of casualties, number of dead
    3) What is being done for the injured
    4) What can the public do now – or is the best thing for them to stay at home, reduce the number of phone calls, etc
    5) Are roads and road access available?

    Reporting can also branch off on a tangent depending on the situation. eg. if there has been a major landslide, and there are no communication links. Then the questions are:

    6) What is the status of communication
    7) Who is doing what about it?
    8) Is there any reason to panic? if not, what are the authorities doing about it.

    A failure to meet these information needs in all three languages will lead to speculation, second-hand information and misreporting. Its up to this core authority to get it right.

    If proper, very fast statements are issued, there is no excuse for news outlets to get it wrong and they won’t.

  15. I shouldn’t be surprised how much repetition is required for learning. I hope others will join, but right now it appears to be dialogue.

    Relevant excerpts from my LBO column of February 2005 written after a visit to the Hilo Civil Defense Center and PTWC:

    On the need for verification:

    “He seemed to like an analogy I had used in a media interview: determining the magnitude of an earthquake is not like sticking a thermometer in someone�s mouth and taking the temperature; it is complex science that involves judgment. Even after you know the magnitude of the earthquake, you have to make another judgment about the likelihood of a tsunami. For people like Weinstein, precision is not the objective; the objective is to warn the people in Hawai`i and around the Pacific if tons of water are barreling their way. They do this on the basis of the first data that comes in, historical data, and judgment. With all the money that�s likely to be poured into this science in the aftermath of the 2004 tsunami, they are likely to get better data and fast computer analysis but there is no likelihood that judgment can be made redundant.”
    A sentence in the following excerpt was the basis for some histrionics by Doug Carlson , who appears to share your position:

    “They are engaged in a polite exchange with PTWC about the timing of the release of disaster information: if CNN carries the story before their phone tree is activated, they get a busy tone which bothers them. I tell them it�s possible to give them priority numbers so their calls will go through. But they are not too keen about shedding ordinary people from the phone system.”

    For the full column:

  16. Please note that our current pilot project is not based on a general-warning model, but on preparing first responders within Sarvodaya to respond quickly.

    General warning can only be done by government. Our report specifies the conditions that need to be satisfied before entities such as Dialog can activate their cell broadcast service.

  17. Many thanks professor for pointing me to your LBO article and Doug Carlson’s blog. The LBO article was an excellent read along with the first-hand insight on your visit PWTC.

    Doug Carlson seems to have lobbied vociferously and consistently over the last two years over the concerns I was wondering about.

    From your LBO article “their first bulletin was out by 0114 GMT (0714 SLT)….By 0204 GMT (0804 SLT) …they issued the second bulletin” Thats 50 minutes.

    How do you see it? Can the international media, and by consequence, local media, be used for disaster warnings?

    I take your point about the general warning needing to come from government. As citizens who pay the salaries of government servants, I guess we will have to push them to deliver.

  18. A relevant e-mail exchange from March 2005 that we intended to move to the web, but never did.

    From Doug Carlson on 3/15/05

    Rohan, I’ve visited your web site, and rather than posting a message there, I’m writing you with these observations and also cc’ing some of your correspondents.

    According to the web site’s account of Chris Chapman’s personal experience, he and his wife were finishing breakfast around 9:30 a.m. Sunday, local time in Ahungalla, Sri Lanka, when the first wave arrived at their beachside hotel. That was 5:30 p.m. Saturday in Hawaii. Here is NOAA’s official time log of events at the Pacific Tsunami Warning Center, shown in Hawaii time with my italicized notes:

    4:04 p.m. [8:04 a.m. Sunday in Sri Lanka] PTWC issues a second Tsunami Information Bulletin to the Pacific revising the earthquake magnitude to 8.5 based on later seismic energy. The bulletin again indicates no tsunami threat to the Pacific, but language is added to advise the possibility of a tsunami near the epicenter. [This alert by the PTWC staff to the Pacific warning system participants specifically mentions the possibility of a tsunami in the Indian Ocean region. This is 84 minutes before Chapman’s assertion of when the first wave arrived at his hotel on Sri Lanka’s west coast.]

    [4:30 p.m.] [8:30 a.m. SLT] PTWC attempts to contact the Australian Bureau of Meteorology to verify they received the bulletin. As their main line was busy, they called Emergency Management Australia instead. EMA indicated Australia was aware of the earthquake. [The PTWC staff makes the first recorded attempt to make what I call “human-to-human” contact another agency, perhaps by telephone, although the method is not stated. Staff scientists are quoted later in numerous media accounts saying they attempted to reach colleagues by making telephone calls.]

    [4:45 p.m.] [8:45 a.m. SLT] Tsunami waves begin striking the coasts of Sri Lanka, India and Thailand. [This apparently is when the first waves arrived in east Sri Lanka, still 45 minutes before they wrapped around to beaches on the west coast.]

    As Chapman noted, the more devastating waves started arriving at 6:20 p.m. Hawaii time, well after scientists had a suspicion of a tsunami and started to alert the Indian Ocean region. NOAA’s own timeline suggests scientists knew enough to have issued what I call usable tsunami warnings through the news media. Instead, they telephoned colleagues and official contacts in the region. Entries on my web log earlier this month recount my conversations and e-mails with the Associated Press, which is an obvious candidate to contact if you need to transmit an urgent message around the world in a matter of minutes. Although the AP’s official position is a bit reserved, I’m sure it would cooperate if asked by the PTWC for channels that would ensure a rapid reaction by a decision-maker. I’ve initiated contact with CNN as well and am waiting for a response on who best is in a position to talk with the PTWC. Once contact is made, much coordination must be conducted to ensure that a credible message from scientists is acted upon appropriately by the news media.

    I’ve been told by the Center’s director that I’ll be invited to visit the Center later this month for a “briefing,” but I hope it turns into more of an “exchange of views.” My ultimate goal is to ensure that the PTWC and the International Tsunami Information Center are more media-oriented than they appear to be at present. (See my March 6 post headlined “Tsunami Crisis Communications Plan Located; Too Bad It Ignores Contacting the International Media” There is a link in that post to the IOC’s web page for the recent Paris conference; scroll down to find a link from there to a PDF file of the plan.)

    Thank you again for your interest in my views. Perhaps change will result more quickly if people in the region such as yourself ask probing questions of the PTWC about its ability and readiness to generate time-sensitive warnings. High-tech solutions eventually will be installed in the Indian Ocean, but a low-tech response can ensure that lives are saved in your country today.

    Aloha, Doug

    Doug Carlson
    Honolulu, HI

    On 3/14/05 1:23 AM, “Rohan Samarajiva” wrote:


    Our custom is to have these kinds of discussions on the web, in public. See for examples.

    We think you are raising important issues that are worth airing in public. Do we have your permission?


    —–Original Message—–
    From: Malathy
    Sent: Monday, March 14, 2005 4:01 PM
    Subject: Re: FW: Tsunami Warnings

    Can we move the exchange to the web – prefaced with your argument on the release of info to the media? Methinks that this debate is useful and ought to be on the web.


    At 03:51 PM 3/14/2005, Rohan Samarajiva wrote:

    Should this exchange be moved to the web (need the guy’s permission though)? My argument is that we can’t give info to the media unless and until we’re sure. He seems to think that knowledge was there at 0804 SLT.


    —–Original Message—–
    From: Doug Carlson
    Sent: Monday, March 14, 2005 12:25 PM
    To: Rohan Samarajiva
    Subject: Re: Tsunami Warnings

    I look forward to reading your web site. My contention is that notification of the Associated Press, CNN, etc. when the warning first went out about a suspected tsunami would have been as much as 45 minutes before the waves struck Sri Lanka. With proper protocols in place, the AP and CNN could have moved the warning over their world-wide networks at the speed of light. Anyone with a radio or cable TV could have received the warning message, and lives would have been saved.

    It is a mystery to me why scientists continue to ignore or discount the role of the news media in transmitting urgent warning messages. My personal experience as a journalist and later a crisis communicator tells me that to ignore the media is to do so at great peril, as we learned on December 26.

    Best wishes and aloha,


    On 3/13/05 6:06 PM, “Rohan Samarajiva” wrote:
    Mr Carlson,

    Thank you for your kind comments. The work we have done since the tsunami on disaster warnings is at < ” xhref=”” mce_href=”” >> .

    I do not agree that PTWC knew about a tsunami as early as you suggest. Knowing that there is an earthquake does not equate to knowing there is a tsunami. If at all, they knew of a likelihood around 0804 Sri Lanka time (0204 UMT). At this time Aceh was gone. 0230 UMT Kalmunai on our East Coast was gone. The level of disorganization at the national level in both Indonesia and Sri Lanka was such that there could have been no systematic response. What we’re working on is that national response.


    —–Original Message—–
    From: Doug Carlson
    Sent: Monday, March 14, 2005 2:56 AM
    To: samarajiva
    Subject: Tsunami Warnings

    Professor, I regret that more than a month has passed since you wrote your long column of 10 February (Surviving tsunamis: What can we learn from Hawaii?) that was published at Lanka Business Online.
    ( < ” xhref=”” mce_href=”” >> Your visit to the Pacific Tsunami Museum and Emergency Operations Center in Hilo, Hawaii was perhaps the best assessment of the communications challenges I’ve read in the two-plus months since the December 26 tsunami.

    I began my web log one week after the tsunami after reading media reports of what the scientists at the Pacific Tsunami Warning Center said they did in the minutes following their realization that a powerful tsunami probably had been generated. My first blog entry was “No Tsunami Warning­Why?” As your column also notes, scientists ineffectively made telephone calls to their colleagues in the Indian Ocean region. They were unsuccessful in transmitting a usable warning and ultimately saved not one life with the knowledge they possessed.

    As a former journalist and with a background in emergency communications, it was immediately obvious to me that the Center’s staff did not make telephone calls that likely would have saved tens of thousands of lives: They did not call the news media. My first post on January 2 linked readers to my letter to the editor that was published in The Honolulu Advertiser on December 30 making that point, and I’ve followed the issue closely since then.

    Something you wrote in your column particularly attracted my attention. You wrote near the end:
    “They (the Big Island’s Civil Defense managers) are engaged in a polite exchange with PTWC about the timing of the release of disaster information: if CNN carries the story before their phone tree is activated, they get a busy tone which bothers them. I tell them it’s possible to give them priority numbers so their calls will go through. But they are not too keen about shedding ordinary people from the phone system.”

    I, too, have been involved in a “polite exchange” with the PTWC. I’ve been assured by Dr. Charles McCreery, Center director, that I’ll be invited to visit the Center this month for a briefing and an exchange of views. I will press my point that if CNN had been alerted directly or through the Associated Press that a tsunami was bearing down on Sri Lanka, hotels and restaurants on the island’s beaches would have carried that warning, and people could have saved themselves with the knowledge. I’ve written Dr. McCreery this month with the recommendation that he initiate contact with the Associated Press to obtain the most efficient way to transmit warnings to the AP on a 24/7 basis.

    You continued in your column to urge training for officials on your home island, but it’s needed elsewhere. I’m convinced the Center’s officials need training on the importance of human-to-human telephone contact with the major international media; electronic messages just get swallowed up in the constant e-mail chatter.

    The recent filing of a lawsuit against NOAA and the PTWC on behalf of tsunami victims puts a new light on the whole issue of who knew what and did what after the earthquake. I have the disquieting feeling that much of what the plaintiffs’ attorneys are saying approximates what I’ve written for the past two months.

    I invite you to read my site when you have time and would welcome your comments.

    Aloha, Doug Carlson

    Honolulu, HI

  19. Many thanks for posting that exchange! Reading Doug Carlson’s blog his last entry suggests that the PTWC is now finally getting media oriented after two years.

    “….Even as a tsunami watch was in effect and Center staffers were assessing the potential for an actual tsunami to arrive after the 8.2 Kuril Islands earthquake last night, at least two Honolulu TV stations were sending “live” reports to its viewers by reporters standing just a few feet away from the computers. Today’s Honolulu Star-Bulletin carries a photo taken last night inside the Center.

    The message was clear: The PTWC was on the job, ready to tell the world USING CONSUMER-ACCESSIBLE NEWS MEDIA whether a tsunami had been generated.

    Emphasis was added to the previous sentence to hammer home the point: PTWC officials now use garden-variety news media to inform the public, something they failed to do in December 2004 when hundreds of thousands died in the Indian Ocean region…..”

    On the concern about releasing information to the media until its verified my view is the following.

    If a person in authority says, or a statement is issued that “there has been a strong 9.2 magnitude earthquake near Sumatra. We do not have any information at present to say that there is a threat of a tsunami, nor do we have any information to say there is no threat of a tsunami. We will release further details as soon as its available,” that is a news story that can be carried by the media.

    What are the consequences of releasing this? Most responsible media institutions will be able to broadcast this verbatim and say “that their neither is nor there isn’t the threat of a tsunami, we are still monitoring developments.”

    If that is the best information available, it needs to be presented to the public.

    Those who want to take a chance will stay indoors, those who don’t want to will move inland. The moment the official can say there is no threat of a tsunami, he needs to do so. The media will carry it, and those who left their homes will head back.

    While I am no expert in the field of disaster warnings and consequent impact on public behaviour, my initial comment is that the above news message, in the case of a “strong earthquake”, is worth being broadcast, and the risk of disruption to public life is worth taking.

    People living on the coast will be grateful for it. The time it gives them to prepare and tune into the next alert is worth it.