Volcano Watch — HVO and NOAA are Pacific Tsunami Monitoring Partner

Release Date:

Recent reports in the local news media mention significant supplemental funding for the National Oceanic and Atmospheric Administration (NOAA) to upgrade its tsunami warning capabilities at NOAA centers in Palmer, Alaska, and Ewa Beach, Hawai`i.

Satellite photograph of an area of Aceh Province, Indonesia

Satellite photograph of an area of Aceh Province, Indonesia, before the December 26, 2004 Indian Ocean tsunami. (Public domain.)

Funds are allocated to upgrade existing systems or purchase new equipment, as well as for adding staff so that NOAA's tsunami warning centers can establish round-the-clock operations. Their goal is to respond and issue a warning even more quickly when there is the possible threat of a tsunami generated by a large local earthquake.

A performance goal for the upgraded tsunami warning system is to reduce the time for NOAA to issue its initial tsunami bulletin, from the present capability of 2 to 5 minutes, to 90 seconds. These extra minutes to react and respond will be very helpful, if not critical.

Accordingly, one cornerstone of an improved tsunami warning system is an improved earthquake monitoring network, including field instruments and data acquisition, analysis, and notification systems. The seismographic network operated by the U.S. Geological Survey's Hawaiʻian Volcano Observatory (HVO) will continue to be a critical element in upgraded and more coordinated earthquake monitoring and reporting for the State of Hawai`i.

While the tragedy of the December 26, 2004, Indian Ocean tsunami provided the impetus for this badly needed boost in support for tsunami monitoring, the importance of improved tsunami monitoring was formally recognized nearly a decade ago in 1997, when NOAA and the U.S. Geological Survey at Menlo Park, California, Golden, Colorado, and HVO, along with university partners in the Pacific Northwest and Alaska, formed the Consolidated Reporting of Earthquakes and Tsunami - or CREsT - partnership.

Like the upgrades just reported this week, CREsT was designed to improve the tsunami warning centers' capabilities by providing them with high-quality seismic waveform data in near real-time from upgraded or newly installed stations. With appropriate analysis programs, they are able to reliably determine earthquake size. Another goal was to reduce the likelihood of issuing false tsunami warnings by rapidly providing to the warning centers earthquake information that could indicate their tsunamigenic potential. These are principally earthquake locations and magnitudes, as determined by HVO or other seismic network operations centers.

Over the communications links established under the CREsT project, HVO continuously sends to the Pacific Tsunami Warning Center (PTWC) in Ewa Beach the raw data from the 3 CREsT seismic stations and two-thirds of our microearthquake monitoring stations. HVO also streams its computer-generated arrival time picks, as well as its automatically calculated earthquake locations, to PTWC. With these different data feeds and analogous, if not redundant, computer data processing utilities at our respective operations hubs, we also hope to avoid discrepant and possibly confusing earthquake notifications to our emergency management customers.

HVO's current volcano microearthquake monitoring network will continue to provide the means to quickly and most precisely locate Big Island earthquakes and pass that information along to PTWC. Improvements to HVO's seismic network, if implemented, will reduce the uncertainties of magnitude estimates. Also afforded will be the ability to generate enhanced earthquake reports that more completely describe earthquakes and their associated effects. The USGS will also be working to bring online upgraded data streams and implement what are becoming standard earthquake data analysis and display modules for reliable and rapid earthquake reporting.

The tsunami stations that will be installed in the coming year will be spread throughout the state. Their greatest advantages will apply to determining magnitudes of larger earthquakes originating beneath and near the island of Hawai'i and to locating the less frequent events beneath the central island chain. Reliably meeting the 90-second reporting requirement, however, will require algorithm development and testing, if not rethinking, as the earthquake source physics might also impose limitations on the speed of magnitude estimation.

Technology promises to only expand our capabilities. Research, development, and thorough testing will all be required to determine when we are collectively able to meet our performance goals and improve upon our tsunami response capabilities.

Volcano Activity Update

Satellite photograph of an area of Aceh Province, Indonesia

Satellite photograph of an area of Aceh Province, Indonesia, after the December 26, 2004 Indian Ocean tsunami. (Public domain.)

Eruptive activity at Pu`u `O`o continues. On clear nights, glow is visible from several vents within the crater and on the southwest side of the cone. Lava continues to flow through the PKK lava tube from its source near Pu`u `O`o to the ocean, with very few surface flows breaking out of the tube. Small flows are visible intermittently on the steep slope of Pulama pali and on the coastal plain. As of September 8, lava is entering the ocean at East Lae`apuki.

The embayment left by the 11-acre bench collapse at East Lae`apuki on August 27 was partly refilled by September 2, when more than four acres of bench had regrown. On September 6, however, at least half of this was claimed by another collapse. Large cracks cross both the old and new parts of the bench.

Access to the ocean entry and the surrounding area remains closed due to significant hazards. If you visit the eruption site, check with the rangers for current updates, and remember to carry lots of water when venturing out onto the flow field.

There was one earthquake felt on Hawai`i Island within the past week. A magnitude-3.2 earthquakes occurred at 8:41 p.m. on Thursday, September 1, 15 km (9 miles) west of Kailua at a depth of 39 km (24 miles); it was felt in Honoka`a, Kailua, Kalaoa, and Kaloko.

Mauna Loa is not erupting. During the week ending September 7, four earthquakes were recorded beneath the summit area. One of them was deep and long-period in nature. Inflation continues.