In the US the Emergency Broadcast System *tests* have been around since the old duck-and-cover days and equally useful... IMO. Teats on a boar?
Useless or not... shouldn't there be an Internet version as well? Where most eye balls are these days?
Maybe an annoying crawler that can be stopped or turned off?
Someone would very quickly write up a blocker to can it.
Most of the time though news travels faster over the internet than it does over older types of media- for instance the shootings in Canada recently I heard about it first from people online before the news here even made mention of it.
Consider too, the majority of the broadcast alerts I've heard on the radio are local or regional alerts issued by the National Weather Service to warn of severe weather in the area. An EBS broadcast transmitted the same way would very quickly prompt people to google "local news", which would right away direct them to their local news stations and the emergency notice that they might not have heard the first time. Radio isn't completely obsolete after all, it still holds a lot of ground in the workplace because it allows people to keep up with news and weather as well as rocking out while they get things done.
And you factor in social networks too- someone hears a tornado warning their facebook now says OMG TORNADO WATCH OUT.
People see this and check their own weather to see if they are in danger as well.
Also, services like this already exist. http://www.emergency...g/PublicServices.asp
When a situation arises that would require the EBS or would trigger a NOAA alert, third party services already exist that send email notices containing the alert. With many people's phones able to recieve emails, this would be highly effective to notify a lot of people right away of a developing situation or a hazard they need to take shelter against.