VOLCANO WATCH: Archive is a Treasure Trove of Volcano Information

Since 1991, USGS Hawaiian Volcano Observatory scientists have written the weekly Volcano Watch column. While the theme of these articles is generally volcano-related, individual topics range widely. They include updates on current volcanic activity, historic accounts of past eruptions, explanations of monitoring techniques and technology, the comings and goings of HVO staff, and more.

With over 1,000 articles on almost every volcano topic imaginable, the Volcano Watch archive is a treasure trove of information on Hawaiian volcanoes. The recent redesign of HVO’s website (itself the subject of Volcano Watch on May 18, 2017) provides an opportunity to highlight this archive, which is online and freely available to all.

You may find past Volcano Watch articles useful for researching a report or school project, while others simply enjoy perusing the collection. Longtime Hawaii residents may appreciate a walk down memory lane, and newcomers might welcome a crash course in the history of volcanic activity in Hawaii.

Since its inception, Volcano Watch has addressed ongoing events at Kīlauea and Mauna Loa. An example is the March 20, 2008, article, “Something had to change after 25 years,” which provides an account of the events leading up to the opening of Kīlauea Volcano’s current summit vent and the return of a lava lake to Halemaʻumaʻu.

The article provides a timeline of when volcanic tremor began and the first explosions were detected at the summit vent. It ends with a question on the origin of the explosions. Subsequent observations have since provided the insight that rock falls into the lava lake are a key trigger for such explosions, making the article a time-capsule for the scientific process.

As illustrated by this example, new data and techniques sometimes cause scientists to change their hypotheses for how or why volcanoes behave in a certain way. Volcano Watch articles communicate these changes, providing updated interpretations as they arise.

For instance, the two-part article, “Revolution in thinking about Kīlauea explosions comes to HVO” (January 19 and 26, 2006), describes the years-long process by which HVO scientists changed their thinking about explosive eruptions at Kīlauea.

Careful mapping of tephra deposits around Kīlauea Volcano’s summit showed that some were the result of ash and other volcanic fragments being thrown up to 5 km (16,000 ft) into the air—high enough to be caught in the jet stream. This suggested that Kīlauea is capable of much more powerful explosions than previously thought, which contributed to it being ranked in a 2005 U.S. Geological Survey report as the highest threat volcano in the United States.

New monitoring instruments and techniques are often the focus of Volcano Watch.  Examples: “Rainbows on the ground” (November 19, 2015), which tells how satellite data is used to measure a volcano’s changing shape, and “Farewell to legacy seismic systems—welcome to ARRA upgrades in Kīlauea Caldera” (July 21, 2011). These articles track the evolution of technology employed by HVO and provide a sense of the myriad methods that scientists use to gain knowledge about volcanoes.

Some of the most timeless Volcano Watch articles detail the history of eruptions in Hawaii. History buffs might enjoy “A look back at Mauna Loa” (December 1, 2011), which recaps observations of the volcano’s 1933 eruption. Another article, “High Chief Keli`ikuku’s pride devastated by unusually long Kīlauea eruption” (June 7, 2007), recounts the story of a large Kīlauea lava flow that devastated most of Puna north of Pāhoa before ending around 1470 CE.

For more recent volcanic activity, check out “Looking back at the Kamoamoa fissure eruption” (March 7, 2013), a four-day event in 2011. If you’ve wondered about the lava flows along Chain of Craters Road in Hawaiʻi Volcanoes National Park, read “The Mauna Ulu eruption: 1969-1974” (May 27, 1994) to learn their origin.

There’s even an article about Volcano Watch!  “The story behind the ‘Volcano Watch’ columns” (September 30, 2010) is in the archive (to reach it, go to “Quick Links” in the top right corner of HVO’s homepage. Click on “Volcano Watch” to open the current article, and then use “Search” to find archived articles by title or date.

Whatever your question is or wherever curiosity takes you regarding volcanoes, the answer or intriguing facts can likely be found in HVO’s Volcano Watch archive.


Volcano Activity Updates

This past week, Kīlauea Volcano’s summit lava lake fluctuated in concert with summit inflation and deflation, with levels ranging 21–41 m (69–135 ft) below the vent rim. On the East Rift Zone, the 61g flow remained active, with lava entering the ocean near Kamokuna and surface flows downslope of Pu‘u ‘Ō‘ō. The 61g flows do not pose an immediate threat to nearby communities.

Mauna Loa is not erupting. During the past week, small-magnitude earthquakes occurred beneath the volcano, primarily in the south caldera and upper Southwest Rift Zone, at depths less than 5 km (3 mi). GPS measurements continue to show deformation related to inflation of a magma reservoir beneath the summit and upper Southwest Rift Zone. No significant changes in volcanic gas emissions were measured.

No earthquakes were reported felt in Hawaii during the past week.

Volcano Watch is a weekly article and activity update written by U.S. Geological Survey Hawaiian Volcano Observatory scientists.