90 likes | 168 Views
New Tsunami Message Definitions SWEPC March 5, 2008. Johanna Fenton Earthquake and Tsunami Program Governor’s Office of Emergency Services. Tsunami Advisory definition revised February 2008 Previously indicated Warning or Watch issued for a section of the Pacific, not CA
E N D
New Tsunami Message DefinitionsSWEPCMarch 5, 2008 Johanna Fenton Earthquake and Tsunami Program Governor’s Office of Emergency Services
Tsunami Advisory definition revised February 2008 • Previously indicated Warning or Watch issued for a section of the Pacific, not CA • Advisories now a low-level Warning indicating moderate tsunami impact possible: • No significant inundation expected for areas under the Advisory • Strong, dangerous currents are possible
Change from message that conveys information to one recommending action • Prompted by the November 2006 Crescent City tsunami - no method to issue tsunami warnings to a specific location without placing the entire state in a Warning • Allows a low level “warning” to be issued between defined break points, rather than for the entire state
Summary • Each product has a distinct meaning relating to local emergency response. Warning -> Inundating wave possible -> Full evacuation suggested Watch -> Danger level not yet known -> Stay alert for more info Advisory -> Strong currents likely -> Stay away from the shore Information -> Minor waves at most -> No action suggested http://wcatwc.arh.noaa.gov/Products/msgdefs.htm
Tsunami Warning • A potential tsunami with significant widespread inundation is imminent or expected • Widespread, dangerous coastal flooding accompanied by powerful currents is possible • Alerts emergency management officials to take action for the entire tsunami hazard zone • Warnings may be updated, adjusted geographically, downgraded, or canceled
Tsunami Watch • Alert for an event which may later impact the watch area. • May be upgraded to a warning or advisory - or canceled. • Emergency management officials and the public should prepare to take action.
Tsunami Advisory • Threat of a potential tsunami with strong currents or waves dangerous to those in or near the water • Coastal regions historically prone to damage due to strong currents induced by tsunamis are at the greatest risk • Significant widespread inundation is not expected • May be updated to continue the advisory, expand/contract affected areas, upgrade to a warning, or cancel the advisory.
Tsunami Information Statement • Inform that an earthquake has occurred, or that a tsunami warning, watch or advisory has been issued for another section of the ocean • In most cases, issued to indicate there is no threat of a destructive tsunami and to prevent unnecessary evacuations • May, in appropriate situations, caution about the possibility of destructive local tsunamis
Questions? johanna.fenton@oes.ca.gov (510) 286-0818