Michael Poland

U.S. Geological Survey Cascades Volcano Observatory, Vancouver, Washington 98683, USA;

Tim R. Orr, James P. Kauahikaua, Steven R. Brantley, Janet L. Babb, Matthew R. Patrick, Christina A. Neal, Kyle R. Anderson*, Loren Antolik, Matthew Burgess, Tamar Elias, Steven Fuke, Pauline Fukunaga, Ingrid A. Johanson, Marian Kagimoto, Kevan Kamibayashi, Lopaka Lee, Asta Miklius, William Million, Cyril Moniz, Paul G. Okubo, A. Jeff Sutton, T. Jane Takahashi, Wes A. Thelen**, William Tollett, and Frank A. Trusdell

U.S. Geological Survey Hawaiian Volcano Observatory, Hawai‘i National Park, Hawai‘i 96718, USA

Abstract

Lava flow crises are nothing new on the Island of Hawai‘i, where their destructive force has been demonstrated repeatedly over the past several hundred years. The 2014–2015 Pāhoa lava flow crisis, however, was unique in terms of its societal impact and volcanological characteristics. Despite low effusion rates, a long-lived lava flow whose extent reached 20 km (the longest at Kīlauea Volcano in the past several hundred years) was poised for months to impact thousands of people, although direct impacts were ultimately minor (thus far). Careful observation of the flow reaffirmed and expanded knowledge of the processes associated with pāhoehoe emplacement, including the direct correlation between summit pressurization and flow advance, the influence of existing geologic structures on flow pathways, and the possible relationship between effusion rate and flow length. Communicating uncertainty associated with lava flow hazards was a challenge throughout the crisis, but online distribution of information and direct contact with residents proved to be effective strategies for keeping the public informed and educated about flow progress and how lava flows work (including forecasting limitations). Volcanological and sociological lessons will be important for inevitable future lava flow crises in Hawai‘i and, potentially, elsewhere in the world.

* Now at U.S. Geological Survey California Volcano Observatory, Menlo Park, California 94025, USA.
** Now at U.S. Geological Survey Cascades Volcano Observatory, Vancouver, Washington 98683, USA.

Manuscript received 3 Sept. 2015; accepted 30 Oct. 2015

doi: 10.1130/GSATG262A.1