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LAVA FLOW—A SILENT VOLCANIC HAZARD IN HAWAII Thursday, October 30, 2014 Walter Hays, Global Alliance for Disaster Reduction, Vienna, Virginia, USA
LAVA FLOW MOVING AT 5 M PER HOUR TOWARDS PAHOA
WHAT HAS HAPPENED? • The lava from Kilauea, a nonexplosive volcano, that has been erupting for years, emerged from a vent in June. • Traveling slowly, it entered Pahoa on Oct. 26, when it crossed a country road at the edge of town.
Thursday, October 30, 2014
LAVA FLOW FROM KILAUEA CONTINUES ITS ADVANCE TOWARD PAHOA
PAHOA HAWAII • A contingent of National Guard troops was dispatched to Pahoa on Thursday, October 30, to provide security to the Big Island community that was being threatened by the slow-moving river of molten lava creeping slowly towards the town's center.
WHAT HAPPENED? • The leading edge of the molten rock stalled at the edge of town on Oct. 30, but lava began to break away at several other upslope spots. . • Between October 30 and November 10, the flow smothered part of a cemetery, and burned down a garden shed, tires, some metal materials, and vegetation.
Monday, November 10, 2014
LAVA FLOW ARRIVES AND SETS FIRE TO FIRST HOUSE
WHAT HAPPENED? • The molten rock set fire to the first house in Pahoa around midday on Monday, November 10 th. • The house was allowed to burn as firefighters took actions to prevent its spread to other houses. • The home's occupants had already left the residence.
WHAT IS NEXT? • Officials are working on safe evacuation routes and plans. • Many residents have evacuated. • Having put their belongings in storage, others are prepared to leave for a friend’s house, or elsewhere, if necessary when the lava gets closer.
ELEMENTS OF VOLCANIC HAZARDS AND RISK
ELEMENTS OF RISK HAZARDS EXPOSURE RISK VULNERABILITY LOCATION
VOLCANOES PART OF THE PACIFIC “RING OF FIRE, ” JAPAN HAS ACTIVE VOLCANOES AS A RESULT OF COMPLEX SUBDUCTION OF THE PACIFIC PLATE BENEATH THE EURASIAN PLATE
100 OF THE WORLD’S 1, 500 ACTIVE VOLCANOES ARE IN JAPAN
CAUSES OF RISK LATERAL BLAST PYROCLASTIC FLOWS FLYING DEBRIS ERUPTIONS ASH PLUME AND GASES CASE HISTORIES LAVA FLOWS VOLCANIC LAHARS TOXIC GASES
VOLCANO HAZARDS CAN HAVE FAR REACHING IMPACTS • VERTICAL PLUME (can affect jet aircraft) • ASH AND TEPHRA • LATERAL BLAST • PYROCLASTIC CLOUDS, BURSTS, AND FLOWS
VOLCANO HAZARDS CAN HAVE FAR REACHING IMPACTS • LAVA FLOWS • LAHARS (can bury villages) • EARTHQUAKES (related to movement of lava) • “VOLCANIC WINTER” (causing famine and mass extinctions)
THE REASONS FOR DISASTERS TO OCCUR. . . • The community is UNPREPARED for what will likely happen, not to mention the low -probability of occurrence— high-probability of adverse consequences event.
THE REASONS ARE. . . • The community has NO DISASTER PLANNING SCENARIO or WARNING SYSTEM in place as a strategic framework for early threat identification and coordinated local, national, regional, and international countermeasures.
THE REASONS ARE. . . • The community LACKS THE CAPACITY TO RESPOND in a timely and effective manner to the full spectrum of expected and unexpected emergency situations.
THE REASONS ARE. . . • The community is INEFFICIENT during recovery and reconstruction because it HAS NOT LEARNED from either the current experience or the cumulative prior experiences.
THE KEYS TO RESILIENCE: 1) KNOW THE ERUPTIVE HISTORY OF YOUR REGION’S VOLCANOES, 2) BE PREPARED 3) HAVE A WARNING SYSTEM 4) EVACUATE 5) LEARN FROM THE EXPERIENCE AND START OVER
VOLCANO RISK • VOLCANO HAZARDS • PEOPLE & BLDGS. • VULNERABILITY • LOCATION DATA BASES AND INFORMATION ACCEPTABLE RISK UNACCEPTABLE RISK HAWAII’S GOAL: VOLCANO DISASTER RESILIENCE COMMUNITIES POLICY OPTIONS HAZARDS: GROUND SHAKING GROUND FAILURE SURFACE FAULTING TECTONIC DEFORMATION TSUNAMI RUN UP AFTERSHOCKS • PREPAREDNESS • PROTECTION • EARLY WARNING • EMERGENCY RESPONSE • RECOVERY and RECONSTRUCTION