Sunday, March 20, 2011

Post-Tsunami Science II --Hokkaido University Institute of Seismology & Volcanology

This is a party at my flat three weeks ago during the visit of Latief, Fujii and Kenji Satake (ERI, Tokyo; photographer). Around the circle from left: Jody Bourgeois, Yuichiro Tanioka, Kei Ioki, Takuji Yamada, Hamzah Latief (ITB, Bandung), Adit Gusman, Yugo Nakamura, Yushiro Fujii (BRI, Tokyo)


I can write a bit more expansively here, because it’s where I’ve been based this winter. Some of my blogs in January talk about and show pictures of Hokudai and its city of Sapporo. Something I saw the other day, but didn’t have my camera to capture—a rally of the Hokudai American football team (since 1976), called “Big Green,” all suited up and yelling so you could hear it halfway across campus.

The institute is focused on the geophysical study of volcanoes, earthquakes and tsunamis. From their website: We install many observation systems such as seismometers, tilt-meters, strain-meters, GPS, tide gauges, etc, in and around Hokkaido. We also carry out campaign surveys using various geophysical instruments in summer time every year. Students who are interested in large earthquakes, volcanic eruptions, or tsunamis, and like to use geophysical instruments in the field are welcome to join us.

Left: late Friday evening, 11 March 2011,

Prof. Emeritus, Minoru Kasahara and Professor Muroto Murakami discuss the possibility that the Jogan events of 869 A.D. are the predecessors to the 11 March 2011 earthquake and tsunami that had been triggered earlier on this day.

Yuichiro Tanioka, Director, ISV

Tanioka is a leading tsunami seismologist. One of his primary foci is the understanding of relationships between earthquake rupture and tsunamigenesis and propagation, in particular using records from tide gages and deep-water buoys. See more below in entry for his post-doc Adit Gusman. Because Yuichiro is Director of the Institute, a big part of his job is to ensure that the researchers in the Institute can all carry out their work. He also acts as a liaison with other institutions as well as with the public. This winter one of his roles, for example, was to be part of an expert panel to analyze damage done to harbors on Hokkaido from the 2010 Chile tsunami. Now look what they have to deal with!

Yuichiro is my official host here, as well as a gracious personal host, and he has been kind enough to take me skiing and also to a Hokkaido Nippon Ham Fighters [pre-season] baseball game in the Sapporo Dome. Friday we had lunch for the first time since before 11 March [usually a group of us has lunch together every day], and he told me a bit about what’s happening, for example:

The seismographs in the affected region on Honshu were all knocked out, and other universities and agencies are trying to put the network back together. This is important to measure all the aftershocks and other related earthquakes that are happening since the big one. Access was hard enough, but the nuclear situation has actually stopped some activity and access entirely. Also, a ship is ready to deploy ocean-bottom seismometers and do other surveying, but it cannot go to sea without clearance vis a vis the potential radioactive fallout. There was a 6.4 earthquake under Fuji not long after the big one offshore, the volcanic seismologists are looking into that; this institution is one that does volcano monitoring.

Also, ISV is making sure their own systems are working well and backed up, because if there is an earthquake on (or offshore) Hokkaido, the help they would normally get from other institutions is not likely to materialize. The big one has loaded nearby faults with additional strain, so earthquakes are more likely to occur in the near future --near being anything from the next week/month to the next few years, or more.

Since the events of 11 March, Yuichiro has also had to communicate a lot with the media – on a typical day he does not wear a suit, but he’s been dressed up all this week. Oh, and this afternoon (Sunday), the institute is sponsoring an informational session for the public about the earthquake and tsunami. Tomorrow is a public holiday, but it will be no holiday for scientists on the front line.

Yuichi Nishimura

Nishimura-san is the investigator here whose current work is most closely related to the kind of work I do—tsunami deposits. He came to our workshop in Seattle in 2005, and then he took me and my students out in the field here in Sapporo for a day in 2006 when I was here for a conference. For some part of the time I’ve been in Sapporo this winter, Yuichi has been in Indonesia surveying deposits from the October 2010 Mentawai tsunami. His geological and geophysical expertise is wide-ranging, and he also is head of the Hokkaido rugby league. And he designed the new logo for the institute --he pointed out to me that it includes layers.

Last Friday night as the tsunami was beginning to arrive on Japan’s coastline, already Yuichi was preparing to go to the field to survey the effects and runup of the Tohoku tsunami on the Hokkaido coast. He left Saturday morning 12 March and returned 18 March, when he was kind enough to take a little time to show me on a map where he went, and to describe how people evacuated successfully (the one fatality a very drunk man, he said), and what the runups were. I look forward to seeing his photographs and report (I’ve offered to help edit English version, a tiny help I can be). The tsunami hit the southern and eastern coasts, particularly, did significant damage in two harbors, and had runups of mostly 3-4 m, the maximum 5-6 m. In case you are thinking that’s small – look up at your ceiling, which is probably about 3 m, and imagine it’s all water up to there.

Nishimura-san has been absent from his office every time I come to take a picture. So far, I have him from our 2006 field trip; in this photo above, the elusive Yuichi is under the baseball cap.

Jun’ichi Miyamura

Miyamura-san is “on loan” from Japan’s Meteorological Agency (JMA) – the NOAA of Japan. He is part of the Scientific Support Section of Hazard Mitigation for Earthquakes and Volcanoes at Hokkaido University. His focus is on education, outreach, and preparedness for natural disasters. His office is open to the room with the big TV screen where we watched the tsunami roll in. That afternoon of the earthquake and tsunami, he tried to watch with us, but his phone was ringing off the hook. Most days when I walk up to the third floor, arriving at work, Jun'ichi is usually already at his desk, and I say "ohaio gozaimas," but the other morning when I arrived, Miyamura-san was out shoveling the snow at the entrance of the institute, so I said "arigato gozaimas."

Takuji Yamada

Takuji is part of our regular lunch bunch and has an outgoing personality. He was a JSPS post-doc at the USGS Hawaii Volcano Observatory for a couple years.

His main research interest is the physics of earthquake source, including rupture speed, stress drop of earthquake, and heterogeneity of slip distribution, that is, strength and dynamic stress level on the fault.

He also has delved into the geophysics of volcanoes, and is involved in observational seismology in general, including in a gold mine in South Africa. I recently caught him outside the building in a group checking out instruments for a deployment. He's the one in the green sweater.

Adit Gusman

Adit recently got his Ph.D. at Hokudai and is now a post-doc at the IVS. He is from Indonesia and represents a major cooperative agreement between Japan and Indonesia for research and education in tsunami science and mitigation. Adit has been modeling tsunamis and their generating earthquakes, based on tide-gage records of the tsunamis. He also is interested in modeling tsunami sediment transport. Since I’ve been here, he and I have been working on reconstructing the 1997 Kronotsky earthquake and tsunami on Kamchatka, but since 11 March 2011, he is of course caught up in these recent events. What an opportune time to be a young tsunami scientist. However, as we all are, Adit is sobered by this giant earthquake and tsunami. Adit and I are friends on Facebook, but most of the posts on his page are in Indonesian, so I get the pictures, but not the words.

To the right is Adit's model of rupture of the 11 March earthuquake based on inversion of tide-gage records -- this is fast work!

Yugo Nakamura

Yugo Nakamura is a post-doc working most directly with Yuichi Nishimura. He gave a talk in our group seminar, early on in my visit, about trying to determine methods for correlating a tsunami deposit from one site to another, testing various methods such as grain-size distribution and microfossil content. This is excruciatingly detailed work, as science commonly is. Yugo appears to be the resident connoisseur of wine from rice and grapes. At our last party, he brought both sake and some local Hokkaido wine. It’s hard for me to shop for these items, not being able to read labels, and particularly, knowing zilch about sake.

Since the earthquake and tsunami, Yugo has been out surveying the coast of Hokkaido. I haven’t seen him since the night of Friday 11 March.

Kei Ioki

Kei is one of a number of graduate students in the Institute, she is doing tsunami modeling and participates on our tsunami seminar, where she gave a talk about her modeling of tsunamis in the Hokkaido-Kurils region.

Photography by Victor Kaistrenko, who was visiting from Sakhalin.

Evening of 11 March 2011 -- this is only the beginning of what will be an all-nighter for most researchers at the Institute of Seismology and Volcanology at Hokkaido University. This night, Yuichiro Tanioka and Adit Gusman were stuck in Tokyo, where they had been for meetings on the day of the giant earthquake.

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