U.S. Deep-Sea Tsunameter Network Fully Operational

completed the deployment of the last of the 39-station network of deep-sea tsunameters. This effort was an integral part of the National Tsunami Hazard Mitigation Program. The Tsunami Program is part of a cooperative effort to save lives and protect property through hazard assessment, warning guidance, mitigation, research capabilities, and international coordination. NOAA’s National Weather Service (NWS) is responsible for the overall execution of the Tsunami Program. This includes operation of the U.S. Tsunami Warning Centers (TWC) as well as leadership of the National Tsunami Hazard Mitigation Program. It also includes the acquisition, operations and maintenance of observation systems required in support of tsunami warning, such as NOAA’s Deep-ocean Assessment and Reporting of Tsunamis (DART®), local seismic networks, coastal, and coastal flooding detectors. NWS also supports observations and data management through the National Data Buoy Center (NDBC). As part of NOAA’s effort to strengthen tsunami warning capabilities, NDBC expanded the network from the original six stations to 39 stations and upgraded all stations from first-generation DART ® I technology to second-generation DART ® II technology. Consisting of bottom pressure recorder and a surface buoy, the tsunameters deliver sea-level data from the sea bottom to tsunami warning centers in less than three minutes. A significant capability of DART II is the two-way communications between the bottom pressure recorder and the Tsunami Warning Centers/NDBC using the Iridium Satellite LLC’s commercial satellite communications system. The two-way communications allow the Tsunami Warning Centers to set stations in event mode in anticipation of possible tsunamis or retrieve the high-resolution (15-s intervals) data in one-hour blocks for detailed analysis. DART II systems transmit standard mode data, containing 24 estimated sea-level height observations at 15