emergency alert systems

emergency alert systems, national public warning systems used by local authorities to deliver important information to affected citizens and communities in an emergency, such as a natural disaster or child abduction. Alerts are activated by government officials and emergency management personnel and can be broadcast by many methods, including via radio and television programming on both satellite and cable networks and via text messages sent directly to mobile devices. Emergency alert systems have helped decrease the number of deaths from natural disasters around the world.

In the United States the Emergency Alert System (EAS) is a collaborative service overseen by the Federal Emergency Management Authority (FEMA), the Federal Communications Commission (FCC), and the National Oceanic Atmospheric Administration (NOAA). Messages will interrupt scheduled programming on television or radio. Networks and providers have a choice regarding whether to carry a local or state alert in the EAS, but they are all required to carry presidential alerts with 10 minutes of notice. FEMA carries national warnings and maintains the system. The National Weather Service, a branch of the NOAA, is responsible for most alerts sent in the United States. The FCC’s role is to set the standards for participant networks.

It was not until 1950 that the NOAA’s Weather Bureau started issuing severe weather alerts to the public. Before this time, it was thought that emergency alerts could lead to panic. As early as 1951, however, American AM radio stations were carrying special broadcasts during emergency events. This developed into the Emergency Broadcast System (EBS) in 1963, which provided a way to address the nation. The EAS replaced the EBS in 1997. Targeted Wireless Emergency Alerts (WEAs) were introduced in 2012; that same year, the first text emergency alert was sent to cell phones in response to flooding in New Mexico. WEAs are delivered to all compatible mobile devices and coupled with emergency tones. The coverage area for the EAS on broadcast and wireless combined reaches more than 90 percent of Americans.

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In Canada the National Public Alerting System is used at the federal, territorial, and provincial levels. As in the United States, it is activated in the event of an AMBER (America’s Missing: Broadcast Emergency Response) alert, a broadcast to seek the public’s help in finding a missing child or missing children. This type of alert is named after Amber Hagerman, a child who was murdered in 1996 in Texas. In addition to the United States and Canada, more than 20 countries, including Spain, Ireland, and South Korea, have similar rapid emergency child alert systems. Nonprofit organizations, such as AMBER Alert Europe, aim to coordinate international responses.

Some natural disasters that commonly warrant emergency alerts are tornadoes, floods, fires, extreme wind, or hazardous material dangers. These warnings are designed to give people time to seek safety—e.g., to head inland or to higher ground in the event of a tsunami or to seek shelter in a basement in the event of a tornado. In 2004 an earthquake in Sumatra caused massive tsunami waves to crash into the shores of Indonesia, Sri Lanka, India, Thailand, and other countries, and more than 225,000 people died. After this disaster, early warning sensors that were intended to give residents at least one hour of notice to seek higher ground during a seismic event were installed off the coast of Indonesia.

Some weather alerts, such as tornado warnings, are also broadcast as outdoor warning sirens. These sound-based emergency alerts first came into widespread use in Europe during World War II to warn of air raids; they are designed to be heard outdoors, usually within a one-to-two-mile radius. Many of the sirens in the United States were installed in the 1950s during the Cold War in case the need arose to warn of a nuclear attack. In 1965 in Minnesota, during one of the state’s worst tornado outbreaks in history, the sirens were used for the first time to warn of approaching tornadoes. These sirens, coupled with TV and radio alerts, were credited with helping to reduce the number of fatalities by prompting people to seek safety.

Because of the increase in natural disasters due to climate change and the disparity around the world in emergency alert systems, the UN’s World Meteorological Organization launched an initiative in 2022 to ensure that every country in the world would develop an adequate early warning system within the next five years.

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Problems with emergency alert systems include false alerts, cybersecurity issues, and the cost of maintaining the equipment used to operate them. In some tornado-prone areas, for example, the tornado warning false alarm rate can be as high as 85 percent, which may cause people to become desensitized to the warnings and fail to take appropriate action in genuinely dangerous situations. In 2018 in Hawaii residents erroneously received a text message warning that a ballistic missile attack was imminent. It took 40 minutes before a correction was issued, and residents panicked. This incident led the FCC to implement changes to the EAS. The new system also allows for immediate corrections, something that was not possible in 2018. Emergency alert systems can also be subject to cybersecurity issues. A notable hack that warned of a zombie apocalypse appeared on TVs in several states in 2013, and in Washington state a false radiological hazard warning was sent out by a hacker in 2020. In 2022 the FCC started requiring that the EAS and the authorities responsible for distributing WEAs notify the commission about all cybersecurity breaches and false alarms within three days. A final drawback to emergency alert systems is the sometimes considerable cost of maintaining some of the equipment.