December 31, 2009
A weekly feature provided by scientists at the Hawaiian Volcano Observatory.
Has it been 27 years already?
Kīlauea has been erupting nearly continuously for 27 years as of Sunday, January 3, 2010. The eruption has gone through many changes in those years, most notably in 2008 with the addition of a second vent and degassing source. While this change made the list of top ten news stories in 2008, it failed to make the grade in 2009 with the tanking national economy, state and county budget woes, and other more immediate concerns taking top honors.
On a longer time scale, the eruption of Kīlauea, or any Hawaiian volcano, is a big deal—in both positive and negative ways. Eruptions destroy structures encourage the tourism industry on Hawai'i Island. While providing abundant land to develop, the threat of destruction by active lava flows affects insurance and mortgage issues, increasing development costs. Eruptions can produce rich soil that supports agricultural products, but also emit vog and volcanic gases that damage crops growing in the volcanic soil.
Hawaiian volcanoes pervade nearly every aspect of our lives. For starters, we would be treading water in the middle of the Pacific Ocean if it weren't for several million years of volcanic activity building islands that provide perpetual footrests.
The soils in which we grow crops and gardens are derived from weathered lava and tephra. Volcanic soils are known worldwide as being rich and well suited for everything from taro to sugar cane, pineapples, and coffee. The needed water is obtained from rainfall scraped from passing clouds by high volcanic ridges.
Living on an active volcano presents many concerns, most of which have been realized to some extent in the past 27 years of Kīlauea's eruption. Lava flows have ignited forest fires and destroyed many structures, subdivisions, and towns, displacing small populations. At the same time, thousands to millions of tourists have been drawn to Kīlauea hoping to witness to Pele's activity. Roads have been blocked and ground traffic rerouted while air tour traffic has increased.
Many Hawai`i Island residents realized first-hand how much of the volcanic gas emissions were going out to sea from Pu`u `Ō `ō vent when a second degassing source in Halema`uma`u Crater opened in early 2008. The location of the new vent directed its emitted gases along the southern part of Hawai`i Island before being blown offshore.
Over the history of humankind, our conflicted relationship with volcanoes has, on the one hand, inspired artists and authors (to be detailed in January Volcano Watch columns) and deity worship (Pele, in Hawai`i) while wreaking local destruction, and, in extreme cases, death. To explore all of these aspects of Hawaiian volcanoes, HVO and our partners have organized a number of educational and experiential activities during January 2010, which is designated as "Volcano Awareness Month."
The "eruption" of volcano awareness activities begins with a kick-off event in Hawai'i Volcanoes National Park on January 2, followed by a special insert in the Hawaii Tribune-Herald and West Hawaii Today newspapers on January 3. A calendar of daily Volcano Awareness Month events in January, as well as a wealth of information about Hawaiian volcanoes, can be found in the insert and on the HVO Web site at http:// hvo.wr.usgs.gov.
Hawai`i is volcanoes and, during Volcano Awareness Month, we encourage you to learn more about this fundamental aspect of our island.
Kīlauea Activity Update
Lava continues to erupt from the TEB vent on Kīlauea's east rift zone and flow through tubes to the ocean at the Waikupanaha location west of Kalapana. Lava flows were active on the pali early in the week, but a deflation-inflation cycle at the summit caused surface activity to slow or stop altogether by midweek.
Glow above the collapse pit inset within the floor of Halema`uma`u Crater, at Kīlauea's summit, has been visible at night from the Jaggar Museum. Lava was visible through an opening in the floor of the collapse pit throughout the week, as recorded by the Webcam perched on the rim of Halema`uma`u. The lava level, however, dropped in response to the deflation-inflation cycle. Volcanic gas emissions remain elevated, resulting in high concentrations of sulfur dioxide downwind.
One earthquake beneath Maui Island was reported felt this past week. A magnitude-3.7 earthquake occurred at 11:39 a.m., H.s.t., on Thursday, December 31, 2009, and was located 53 km (33 miles) north of Kahului, Maui, at a depth of 19 km (12 miles).
Visit our Web site (http://hvo.wr.usgs.gov) for detailed Kīlauea and Mauna Loa activity updates, recent volcano photos, recent earthquakes, and more; call (808) 967-8862 for a Kīlauea activity summary; email questions to askHVO@usgs.gov.
Updated: January 4, 2010 (pnf)