The following is this week’s edition of the USGS Hawaiian Volcano Observatory‘s Volcano Watch:
With the recent downgrade of the Volcano Alert Level for Kīlauea’s June 27th lava flow that has been threatening the Pāhoa area, it’s interesting to take a look back at the 1880-1881 Mauna Loa lava flow and the threat that it posed to Hilo.
On the evening of November 5, 1880, people in Hilo and at the Volcano House hotel at the summit of Kīlauea noticed a glow on Mauna Loa—produced by an eruption located northeast of the volcano’s summit. A vent at about the 3,200 m (10,500 ft) elevation produced one lava flow that moved to the southeast and stalled about 2.5 km (1.5 mi) from Highway 11 near Kīlauea caldera. A second vent, immediately downslope of the first, erupted a pāhoehoe lava flow that advanced to the northeast toward Hilo.
By January 1881, the northeast flow was estimated to be about 30 km (18 mi) from Hilo. This flow was of interest to Hilo residents, but not a big concern. However, by April, the flow had split into three branches in the vicinity of what is now Kaūmana City, a subdivision at the upper Hilo city limits, and advanced to within 11 km (7 mi) of the town. By the beginning of July, a single branch was only 4 km (2.5 mi) from Hilo.
The flows were initially difficult to access. But by July, the flows had moved close enough to Hilo that residents and visitors alike were frequently trekking up to the flow to watch its progress. They observed that the pāhoehoe would advance very quickly as narrow fingers for short periods of time and then stall, only to repeat the process a few hours or days later. Astonishing stories of narrow lobes of lava advancing hundreds of feet in a few hours were common.
Observers would occasionally note that the lava sometimes occupied a ravine or gulch where water flowed during heavy rains. As the flows got closer to Hilo, people often noticed that warm water seemed to flow out from under the active lava.
As the eruption continued, Hilo residents became alarmed, and many started moving their belongings out of harm’s way. The branch closest to Hilo split into two lobes, with one headed down ‘Alenaio gulch toward the center of Hilo, and the other headed down Kalanakāma‘a gulch (near and parallel to Mohouli Street) toward the Waiākea Fishponds and Sugar Mill (Wailoa State Park). Everyone feared that the lava would cut through town and enter Hilo Bay.
Just as concern was getting intense, the leading tips of both lobes stalled on or about August 10th with the Kalanakāma‘a lobe a little more than 1.6 km (1 mi) from Hilo Bay. The ‘Alenaio lobe didn’t quite reach Komohana Street. The lava had destroyed only one house near the current location of Kaumana Elementary School. By August 19th, the lower portions of the flow were inactive.
This Mauna Loa flow differed from Kīlauea’s June 27th flow in two significant ways. The Mauna Loa 1880–1881 flow is about twice the length of the June 27th flow, and the Mauna Loa eruption rate was probably higher.
But there were also some similarities. The Mauna Loa 1880–1881 and the Kīlauea June 27th lava flows were both pāhoehoe and were active for about 9 months before their threats were reduced. Both flows greatly concerned the people who lived and worked downslope of the advancing fronts, but the flows consumed only a single house before their leading edges stalled. And both flows cut a swath through heavily forested land.
But in the case of the 1880–1881 Mauna Loa flow, the open swath it cut through the forest eventually improved travel from Hilo to Waimea and Kona via the saddle between Mauna Loa and Mauna Kea. Years later, the Saddle Road, as it is now known, took advantage of this path. Today, Saddle Road crosses four Mauna Loa flows—the 1880–1881, 1855–1856, 1899, and 1935 flows—between mile markers 3 and 29.
While the 1880–1881 Mauna Loa eruption may have had a beneficial aspect—blazing a trail for Saddle Road—that’s not always the case with active lava flows.
Volcano Watch (http://hvo.wr.usgs.gov/volcanowatch/) is a weekly article and activity update written by scientists at the U.S. Geological Survey`s Hawaiian Volcano Observatory.
National Park of American Samoa’s park rangers, staff, and crew came together to wish our Superintendent Jim Bacon best of luck in his future endeavors on the U.S. mainland. Gifts and some of the island tokens were given to him to remember us by and to remind him that there is always “family” waiting for him in case he decides to come back to visit American Samoa.
Message from Superintendent Jim Bacon:
“My family and I have enjoyed our time in American Samoa over the last two-and-a-half years. It has been an honor and absolute privilege to work with a group of people that truly care for one another, their culture, and their natural environment. We will surely miss this wonderful place and all of the people we have come to know, but we will certainly stay in touch.
Tofa soifua Amerika Samoa!”
On Saturday, March 21, eight middle school students graduated from Haleakalā National Park’s Kupukupu `Āina internship program. The middle school program is held each year during spring break.
Interns explored the diverse habitats of Haleakalā by hiking several trails and helped park resource managers work with endangered species. They removed over 600 invasive plants and assisted with trail maintenance. Interns learned about national park law enforcement and practiced emergency medical skills via mock scenarios. The students also received job and career counseling through workshops offered by staff from the Maui County Human Resources office and the University of Hawaii Maui College’s CareerLink office.
Funding for the program was provided by non-profit partners Hau`oli Mau Loa Foundation, Tri-Isle Resource Conservation & Development Council, and the Hawai`i Pacific Parks Association.
Hawai‘i Volcanoes National Park is seeking volunteers to help us celebrate and document biodiversity at the National Geographic/National Park Service BioBlitz and Biodiversity & Cultural Festival, happening here May 15 and 16th. There are tons of volunteer opportunities, from set-up to scientific inventories.
Learn more and sign up here.
The following is this week’s edition of the USGS Hawaiian Volcano Observatory‘s Volcano Watch:
Over the past few months, Mauna Loa, Hawaiʻi Island’s largest volcano, has shown subtle signs of stirring from its 31-year-long slumber (its most recent eruption began on March 25, 1984). The U.S. Geological Survey’s Hawaiian Volcano Observatory (HVO) has recorded numerous small earthquakes beneath Mauna Loa’s summit and western flank, and has detected slight expansion across Mokuʻāweoweo, the volcano’s summit caldera—signals that Mauna Loa should not be forgotten!
What can we expect as this great volcano reawakens and builds toward its next eruption?
Generally, as magma rises and eventually infiltrates and fills Mauna Loa’s summit magma reservoir, pressure builds within the volcano. When sufficient pressure is achieved, the volcano expands to accommodate the additional volume of molten rock within it. During this expansion, the flanks of the volcano move apart and the summit moves upward. The increased pressure also generates stresses that result in earthquakes, which accounts for the increased numbers of earthquakes recently recorded by HVO’s seismic network. Historical accounts of the effects and felt reports of earthquakes suggest that many of Mauna Loa’s 33 eruptions since 1843 were preceded by precursory earthquake activity.
HVO tracks activity at Mauna Loa with a variety of tools including Global Positioning System (GPS) receivers, tiltmeters, radar satellites, gas sensors, remote cameras, and seismometers. We use patterns seen in all of these data to forecast when the volcano might erupt.
Instrument-based volcano monitoring in Hawaiʻi began when HVO was established in 1912. The emergence of electronics in the 1950s and 1960s gave rise to networks of seismographs and laser-ranging Electronic Distance Measurement (EDM) instruments that greatly improved our ability to monitor and forecast volcanic activity.
Mauna Loa’s two most recent eruptions, in 1975 and 1984, occurred as HVO expanded and modernized its seismic and geodetic monitoring networks. Examining these past eruptions can give us insight into how Mauna Loa will behave in future eruptions.
Prior to the 1975 eruption, the length of an EDM line spanning Mokuʻāweoweo lengthened as magma accumulated within the volcano and caused it to inflate. In addition, more than a year before lava erupted in July 1975, HVO recorded a significant increase in earthquakes, with the seismicity concentrated in two distinct regions within the volcano. Earthquakes initially clustered northwest of Mauna Loa’s summit at depths between 5 and 10 km (3–6 mi) were followed by shallow earthquakes that were concentrated less than 5 km (3 mi) beneath the summit. In the months leading to the 1975 eruption, the number of earthquakes dramatically increased, reaching levels of several hundred events per day.
The sequence of ground deformation and seismicity followed a similar pattern prior to Mauna Loa’s 1984 eruption. Increased numbers of earthquakes were again seen in the two areas where seismicity was concentrated before the 1975 eruption, and EDM measurements across Mokuʻāweoweo showed extension (inflation) months before the 1984 eruption.
How do current observations of Mauna Loa compare to the previous two eruptions?
The recent swelling of the volcano is small compared to that observed in 1975 and 1984. Earthquake activity, while notable, is also modest. In terms of magnitude, recent earthquakes beneath the volcano’s northwest flank have not yet reached levels recorded before the 1975 or 1984 eruptions. Additionally, the number of earthquakes beneath the summit is not yet significant. Overall, we expect more persistent and heightened rates of both ground deformation and seismicity as the volcano nears its next eruption.
Recent improvements in HVO’s monitoring capabilities enhance our ability to watch for and track changes on Mauna Loa. With upgrades to and expansion of our seismic network and the installation of additional of GPS stations, tiltmeters, gas sensors, and webcams, we can better monitor Mauna Loa and other active Hawaiian volcanoes. This, in turn, helps improve our understanding of how these volcanoes work and our ability to forecast eruptions.
The take-home message today is two-fold: (1) Mauna Loa is an active volcano, but an eruption is not imminent, and (2) HVO closely monitors Mauna Loa and will immediately inform authorities and the public if significant changes in activity are detected. For now, monthly reports on the status of Mauna Loa are posted on HVO’s website at http://hvo.wr.usgs.gov/activity/maunaloastatus.php.
Student Conservation Association(SCA) positions at Kaloko-Honokohau NHP and Pu’uhonua o Honaunau NHP
Student Conservation Association
Kaloko-Honokōhau National Historical Park
Pu‘uhonua o Hōnaunau National Historical Park
Twelve week Visitor Services Internship – Summer 2015
The Student Conservation Association works with National Parks across the country to provide internships for career development in resource management, visitor services and other career fields.
The internship will allow students to:
Explore NPS careers and fields by working at a Hawaii National Park! A great resume builder!
Internship focus areas include visitor services, education, resource management, and more!
How to Apply:
1. Complete an Internship/Corps Application online at thesca.org and apply for ‘Visitor Services Intern’, upload your resume.
2. Contact Park Ranger Jon Jokiel at (808)329-
6881 ext. 1329 if you have any questions!
• Weekly stipend of $175
• Assigned NPS mentor
• Hands-on experience working at a National
Park with park staff and other organizations
• Additional career preparation and ongoing support
• US citizen
• At least 18 years old
• Housing and transportation required
The following photos were released by the Hawaiian Volcano Observatory (USGS) (Dated March 17, 2015) . Note: these photos were not taken in areas currently accessible to the public. (You can visit the official website of Hawai’i Volcanoes National Park for current information on the areas of Kilauea that are open to public).