The 6th Joint Meeting of the UJNR Panel on Earthquake Research

Present situation of monitoring, prediction and information for volcanic disaster mitigation in

Koji Aizawa

Division of Volcanology Department of Seismology and Volcanology Japan Meteorological Agency JMA Today’s Contents

‹ Overview of Volcanic Disaster mitigation Operated by JMA

‹ Example of Recent Response for Volcanic Disaster by JMA and Local Authorities

JMA Active Volcanoes in Japan

Definition of ACTIVE volcanoes : Volcanoes that erupted in recent 10,000 years or have vigorous fumaroles TOTAL: 108 volcanoes

JMA Volcanic eruption of last 10 years in Japan

Year9697989900010203040506 Meakan-Dake ▲▲ ▲ Tokachi-Dake ▲ Usuzan ▲▲ Hokkaido Komagatake ▲▲▲ Akita Yakeyama ▲ Asamayama ▲▲ Miyakejima ▲▲▲ ▲▲▲ Izu-Torishima ▲ Iwo-jima ▲▲ Fukutoku-oka-no-ba ▲ Kuju-san ▲ Asosan ▲▲▲ Sakurajima ▲▲▲▲▲▲▲▲▲▲▲ ▲ Satsuma-Iwo-jima ▲▲▲▲▲▲▲ eruption occurred Suwanose-jima ▲▲ ▲▲▲▲▲▲▲▲ JMA Moyoro-Dake ▲ Active Volcanoes in Japan and Observations and Information Centers (VOICs)

Area of responsibility Sapporo VOIC

Sendai VOIC Sapporo VOIC Taisetsuzan Ruruidake Rishirizan Atosanupuri Shiretoko-Iozan VOIC Etorofu-Atosanupuri Yoteisan Tokachidake Rausudake Chirippusan Niseko Fukuoka VOIC Moyorodake Usuzan Hokkaido-Komagatake Sashiusudake Odamoisan Io-Torishima Oshima-Oshima Nansei Etorofu-Yakeyama Iwakisan Berutarubesan Hakkodasan Mashu Chachadake Submarine Volcano Raususan NNE of Iriomotejima Akita-Yakeyama Eniwadake Tomariyama Akita-Komagatake Maruyama Esan Meakandake Chokaisan Tarumaesan Osorezan Kuttara Bandaisan Hijiori Niigata-Yakeyama Towada Numazawa Sendai VOIC Kusatsu-Shiranesan Fukuoka VOIC Midagahara Hiuchigatake Hachimantai E140° E144° Myokosan Iwatesan Yakedake Kurikomayama Akandanayama Beyonesu Rocks N32° Abu Volcanoes Naruko Norikuradake Zaozan Sumisujima Sanbesan Hakusan Azumayama Izu-Torishima Ontakesan Adatarayama Sofugan Unzendake Nasudake Takaharayama Fukue Volcanoes Nikko-Shiranesan N28° Yonemaru and Akagisan Nishinoshima Sumiyoshiike Harunasan Kaikata Seamount Ikeda and Yamagawa Tsurumidake Toshima Asamayama Kaitoku Seamount Yokodake Kaimondake Funka Asane and Garandake Niijima Izu-Oshima Iojima Satuma-Iojima Yufudake Fujisan Miyakejima Kita-Fukutokutai N24° Kuchinoerabujima Kujusan Hakoneyama Fukutoku-Okanoba Kuchinoshima Asosan Tokyo VOIC Minami-Hiyoshi Izu-Tobu Seamount Kirishimayama Nikko Seamount Nakanoshima Volcanoes Wakamiko Hachijojima Suwanosejima Kozushima Sakurajima Aogashima Mikurajima Izu-Ogasawara Islands

26 volcanoes written with red letters are continuously monitored by JMA. Disaster VOIC Prevention General Public Authorities, Mass Media Collaborative work with researchers Meteorological Observatories

Volcano Detailed Analysis of ・ Seismic and Geodetic data Information ・ Volcanic fumes activity

Volcanic Regular Bulletin Diagnosis of Volcanic Activity Tiltmeter

24 hours Watch Data Analysis Real-time telemeter Quick look analysis and watch of data Issuance of Volcano Information

Dispatch of Mobile Observation Team Mobile Observation Team

Regular survey of volcanoes Emergency observation of volcanoes VOIC GPS Infrasonic Seismometer High-sensitive Microphone Visual Camera Volcano Information and

Volcano Information

Volcanic Alert is issued when volcanic activities are Volcanic Alert extremely intensified and urgent countermeasures to prevent/mitigate damage to human lives are required.

Volcanic Advisory is issued when unusual volcanic Volcanic Advisory phenomena are observed and preparation for disaster prevention/mitigation is required.

Volcanic Volcanic Observation Report is issued as supplemental Observation Report information to Volcanic Alert and/or Volcanic Advisory.

Bulletin of Volcanoes Volcanic Regular Bulletin (Monthly) Monthly Report on Earthquake and Volcanoes in Japan JMA Weekly Report on Earthquake and Volcanoes in Japan Volcanic Activity Levels by JMA

Volcanic Activity Levels ５ VERY LARGE ERUPTION ALERT

４ LARGE-MIDDLE ERUPTION Volcanic ObservationReport A DV. ３ SMALL ERUPTION, CAUTION

２ ACTIVE

１ CALM

０ DORMANT Dessimination of Volcano Information

Volcano Information Coordinating Committee of Prediction of Volcanic Eruption

１９７４～ Members : Volcanologists and public offices Universities Research Institutes (NIED, GSJ, PWRI) Geological Survey Institute Ministry of Land, Infrast- ructure and Transport Cabinet Office Ministry of Education Japan Coast Guard Japan Meteorological Agency (Secretariat) Eruption of Asama volcano in 2004 Distribution of continuous observation points at Asama by JMA as of March 2006

■: Seismometer ◆: Infrasonic microphone, ◎: Seismic intensity meter ☆: Tiltmeter ●: GPS ★: Visual camera.

JMA Level Volcanic activity Eruption Very large eruption or possibility Pyroclastic flow and/or flow Pyroclastic flow and/or lava flow reach to the town 5 reach to distant area from distant from the mountain. the mountain. Volcanic bombs reach to the town (more than 3km Large eruption or possibility distant from the crater). 4 Big explosion affects the town. Small pyroclastic flow, air shock affects the houses in the town. Explosive eruption at the summit crater or possibility Explosive eruption. Explosion occurs. or Volcanic bombs reach to the mountain slope (within 3 Precursor of eruption e.g. 3km distant from the crater) Large flux of volcanic gas Very small pyroclastic flow Seismic swarm Glowing etc. Active Volcano is rather active. e.g., 2 Very small eruption might occur occasionally. Volcanic gas increases Volcanic earthquakes Calm 1 Activity of volcanic quakes, Low possibility of eruption smokes and others is low. 0 Dormant No possibility of eruption The restriction rule of the climbing mountain according to the level

The rule for off-limits of Asama

Level 0 : No restriction Level 1 : Off-limits within 500m from the crater. Level 2 : Off-limits within about 2 km from the crater. Level 3 : Off-limits within 4 km from the crater.

JMA MLIT(2004) Volcanic glow before eruption

‹ The photo was taken on 7 August 2004 from Karuizawa Weather Station about 8km south of the vent. ‹ Volcanic glow was observed only at night by highly sensitive video camera from 25 July 2004 about 1 month before the eruption. JMA Eruption at 20:02 on 1 September 2004.

• Upper left: Right after the eruption, light of plume was seen through the clouds. • Upper right: After that, volcanic bombs scattered as far as 2km from the vent. • Lower: An example of photo taken in fine weather. Red dotted line shows the area where volcanic bombs scattered on 1 September 2004. Eruption in 2004

300 200 Volcanic quakes Eruptions 100

0 2003/10/1 2003/12/1 2004/2/1 2004/4/2 2004/6/3 2004/8/3 2004/10/4 2004/12/4 5 4 3 Volcanic Activity Level 2 1 0 2003/10/1 2003/12/1 2004/2/1 2004/4/2 2004/6/3 2004/8/3 2004/10/4 2004/12/4 The local governments 50 40 forbade entering the area 30 Hourly number of quakes EXP. 20 within 4km from the 10 active crater! 0 2004/8/31 0:00 2004/9/1 0:00 2004/9/2 0:00 2004/9/3 0:00 LEVEL 2 LEVEL 3 Observation Report Precursor of eruption at Asama

Tilt change and B type earthquakes before several to 30 hours

Explosions Precursors Predicted Sep. 1 ○△ Sep. 23 ○× Sep. 29 ○○ Oct. 10 ×× Nov. 14 ○○ No Explosion Oct. 6 ○－ Feb. 21-22 ○－

JMA

22 23 24 25 September 2004 Ground deformation and volcano information

9月27日 9月28日 9月29日 9月30日 Erup tion On 29 September S-up,W-up 0.2μrad At 00:43 volcano info. Volcano information At 08:15 volcano info. Volcano information At 12:17 eruption

Hourly frequencies of BH type volcanic earthquakes

JMA 9月27日 9月28日 9月29日 9月30日 Summary There are difficulties to exactly predict volcanic eruption on present technical level.

But, at volcano where monitoring system is operating, some eruptions rarely occur completely without precursors, so we can issue Volcano information before eruption in some case.

For volcanic disaster mitigation, it is important to operate volcanic monitoring system and issue adequate information to the public. JMA ありがとうございました。 Thank you!

Official mascots of JMA “Hare-run”