Geoscience Reference
In-Depth Information
discussion on this AOR issue in Chapter 5). Although these messages are not intended for pub-
lic consumption (Paul Whitmore, NOAA, personal communication), products from both TWCs
are distributed to members of the public and the media who have signed up on the TWCs'
websites to receive these alerts. Consequently, the messages are immediately disseminated
to the public via television, radio, and the Internet—as was the case during the 2009 Samoan
tsunami (Appendix I) and the 2010 Chilean tsunami (Appendix J).
The generation of two sets of warnings, although technically appropriate due to different
areas of responsibilities, can be a major source of confusion among the emergency manage-
ment community and the public, as illustrated by the June 14, 2005, event (Appendix F). During
the 2005 event, media outlets in the Paciic Northwest received messages from both TWCs
that appeared to contradict each other because the distinction between areas of responsi-
bility was not well understood. It is likely that media outlets and the public will continue to
misunderstand this jurisdictional distinction in future warnings. Therefore, it is central to the
success of the TWCs that they further improve the consistency and clarity between their mes-
sages to prevent any confusion resulting from the distinct AOR. Alternatively, the issuance of a
single message after internal consultation between the TWCs could deinitively eliminate the
potential for confusion from differences in message content.
Local oficials will receive warning messages from the TWCs typically within ive minutes
of an event. Information will come via the NAWAS to the state warning centers and via state
versions of the warning system (e.g., HAWAS) to county Public Safety Access Points (PSAPs or
911 dispatch) if a warning has been issued. If the jurisdiction is an incorporated municipality,
warning messages are sent from the PSAP and law enforcement teletype to the local dispatch.
If local oficials are directly linked to seismic network displays (e.g., the California Integrated
Seismic Network (CISN)), then they will receive conirmation of the earthquake via both
ShakeMap
4
and TWC documentation. Once local oficials decide to issue an evacuation order,
they will issue it via pre-determined channels (e.g., sirens, AHAB (All-Hazard Alert Broadcast),
reverse-911 calls, etc.).
It is important to note that current dissemination routes and plans described by the TWCs
and local emergency management resemble the old paradigm of a linear message pathway
from the warning center to the local emergency oficials, who then notify the public and order
an evacuation. Such a linear information transfer can no longer be assumed with the rise of the
Internet and other telecommunications technology. Instead, communication networks resem-
ble a web of sources with information coming from multiple systems, both oficial (e.g., local
sheriff, NOAA Weather Radio (NWR)) and unoficial (e.g., TV, Internet, friends). As mentioned
earlier, the media and many members of the general public now receive alerts directly from the
TWCs, thereby removing local emergency management from the communication path.
Another factor likely to change warning messaging is mobile social networking technol-
ogy (e.g., Twitter, Facebook, and Google Maps). These technologies have all been harnessed
4
ShakeMap is a product of the USGS Earthquake Hazards Program in conjunction with regional seismic network
operators. ShakeMap sites provide near-real-time maps of ground motion and shaking intensity following signiicant
earthquakes.
