	Introduction: U.S. Tsunami Warning Centers

The United States has two centers that monitor, detect, and issue warnings for tsunamis. The National Oceanic and Atmospheric Administration's (NOAA's) National Weather Service (NWS) manages both centers. The NWS operates the Pacific Tsunami Warning Center (PTWC) at Ford Island, Hawaii, and the National Tsunami Warning Center (NTWC) at Palmer, Alaska. Detecting Tsunamis and Issuing Warnings

The tsunami warning centers monitor and evaluate data from seismic networks and determine if a tsunami is likely based on the location, magnitude, and depth of an earthquake. The centers monitor coastal water-level data, typically with tide-level gauges, and data from NOAA's network of Deep-Ocean Assessment and Reporting of Tsunamis (DART) detection buoys to confirm that a tsunami has been generated or, if one has not been generated, to cancel any warnings. P.L. As of November 18, 2015, 4 of the 39 U.S. buoys (10%) were not operational. This represents an improvement over the course of the year; in March 2015, 9 of the buoys were not operational (23%). The inoperable stations likely would not prevent the issuance of tsunami warnings, which are primarily a function of seismic data from an earthquake or landslide, combined with location information about the event. The National Tsunami Hazard Mitigation Program

According to NOAA, the National Tsunami Hazard Mitigation Program (NTHMP) was formed in response to the recognition of a tsunami threat to Oregon, Washington State, and Northern California from a large earthquake on the Cascadia subduction zone, which lies off the northwest coast of the United States and is capable of generating earthquakes as large as magnitude 9 or greater. Among other activities, the NTHMP assists states in emergency planning and in developing maps of potential coastal inundation for a tsunami of a given intensity. The NTHMP also operates tsunami disaster outreach and education programs in support of NOAA's TsunamiReady program. Issues for Congress

Maintenance and availability of the DART buoy network have been key issues for Congress. 109-424 , Congress stated that "maintaining operational tsunami detection equipment is the highest priority within the program carried out under this Act." 34 , the Tsunami Warning, Education, and Research Act of 2015, on January 7, 2015, by unanimous consent. The Senate passed its version of the legislation, as an amendment in the nature of a substitute for H.R. 34 , on October 6, 2015, by unanimous consent. Reauthorization of the National Tsunami Hazard Mitigation Program: Legislation in the 114th Congress

Both versions of the legislation would amend the Tsunami Warning and Education Act and authorize appropriations for the NTHMP through FY2017 ( H.R. 34 ) or through FY2021 ( S. 533 ). Authorization for the program's appropriations in P.L. 109-424 expired in FY2012. Both bills apparently would not make fundamental changes to the NTHMP but would broaden the program to include an additional focus on tsunami research and outreach, among other alterations. In subsection (b), the Senate-passed version would require that 80% of the DART buoys be maintained at operational capacity. During FY2015, NOAA reorganized portions of its budget and aligned costs for the tsunami activities into two accounts: DART buoys are funded out of Observations Programs, Projects, and Activities (PPA), and all other tsunami activities are funded out of Analyze, Forecast, and Support PPA. For tsunami activities in FY2015, NOAA allocated $12.2 million under Observations PPA and $19.2 million under Analyze, Forecast, and Support PPA, for a total of $31.4 million. The FY2016 budget request was $6 million less than the FY2015 enacted amount (representing a $6 million reduction in the NTHMP grant funds, similar to the Administration's FY2015 request).
The National Oceanic and Atmospheric Administration's (NOAA's) National Weather Service (NWS) manages two tsunami warning centers that monitor, detect, and issue warnings for tsunamis. The NWS operates the Pacific Tsunami Warning Center (PTWC) at Ford Island, Hawaii, and the National Tsunami Warning Center (NTWC) at Palmer, Alaska.
The tsunami warning centers monitor and evaluate data from seismic networks and determine if a tsunami is likely based on the location, magnitude, and depth of an earthquake. The centers monitor relevant water-level data, typically with tide-level gauges, and data from NOAA's network of Deep-Ocean Assessment and Reporting of Tsunamis (DART) detection buoys to confirm that a tsunami has been generated or to cancel any warnings if no tsunami is detected. As of November 18, 2015, 4 of the United States' 39 DART buoys (10%) were not operational. This figure represents an improvement over the course of the year; in March 2015, 9 of the buoys were not operational (23%). The inoperable stations likely would not prevent the issuance of tsunami warnings, which are primarily a function of seismic data from an earthquake or landslide, combined with location information about the event.
On January 7, 2015, the House passed by unanimous consent H.R. 34, the Tsunami Warning, Education, and Research Act of 2015. The bill would amend the Tsunami Warning and Education Act (P.L. 109-424) and authorize appropriations for the National Tsunami Hazard Mitigation Program (NTHMP) through FY2017. Authorization for NTHMP appropriations expired in FY2012. On February 23, 2015, the Senate introduced its version of the bill, S. 533, which would authorize appropriations for six years through FY2021. On October 6, 2015, the Senate passed its legislation as an amendment in the nature of a substitute for H.R. 34 by unanimous consent. Neither bill would make fundamental changes to the NTHMP, but both would broaden the program to include an increased focus on tsunami research and outreach, among other alterations.
The NTHMP assists states in emergency planning and in developing maps of potential coastal inundation for a tsunami of a given intensity. A goal of the program is to ensure adequate advance warning of tsunamis along all U.S. coastal areas and appropriate community response to a tsunami event. The NTHMP formed in 1995 in response to the recognition of a tsunami threat to Oregon, Washington, and Northern California from a large earthquake on the Cascadia subduction zone, which lies off the northwest coast of the United States and is capable of generating earthquakes as large as magnitude 9 or greater. The NTHMP also operates tsunami disaster outreach and education programs that support NOAA's TsunamiReady program.
During FY2015, NOAA reorganized portions of its budget and aligned costs for tsunami activities into two accounts. For FY2015, $12.2 million was allocated under Observations Programs, Projects, and Activities (PPA), and $19.2 million was allocated under Analyze, Forecast, and Support PPA, for a total of $31.4 million. The FY2016 budget request is $6 million less than the FY2015 enacted amount.
Key issues for Congress include maintenance and availability of the DART buoy network. P.L. 109-424 states that "maintaining operational tsunami detection equipment is the highest priority within the program carried out under this Act." The House-passed bill would require that "the Administration's operational tsunami detection equipment is properly maintained," but the Senate-passed version would be more specific and require, "to the degree practicable, [the maintenance of] not less than 80 percent of the [DART] buoy array at operational capacity."