Volcano Research Research Articles

Open Science Initiatives by Sakurajima Volcano Observatory

The sudden eruption and tragedy of Mt. Ontake in 2014, a volcano located in central Japan, showed the fact that the volcanic eruption is the event with uncertainty, and it is important to let citizen to be aware of such uncertainty. To find measures to raise citizen’s disaster awareness, this study focuses on the risk communication between citizens and volcano observatories, which are attached to universities. It examines the role of observatories, focusing on the activities of the Sakurajima Volcano Research Center, which monitors Mt. Sakurajima, one of the most active volcanoes in Japan, and suggests the necessity of human resource development that is able to connect citizen and science.

Progress in Saving Lives Aspects of Emergency Management Since the 2014 Mt. Ontake Eruption

Introduction:Mt. Ontake (3,067m), Japan's second-highest volcano, erupted without warning on September 26, 2014, leaving 58 dead and five people missing. More than 20,000 rescue workers were mobilized from all over the country. The findings on rescue operations and subsequent advances in emergency preparedness and rescuer education are presented.Method:After the disaster, public data was obtained from the Cabinet Office by conducting interviews. Photographs and videos were collected from the military, the police, and the Fire and Disaster Management Agency sources, as well as from local governments and the Volcano Research Institute.Results:The volcanic eruption received governmental disaster designation. The leading cause of death and the rescued survivors were traumatic injuries caused by sudden falling rocks. Volcanic tremors and landform upheaval were observed immediately before the eruption, but they were too short-lived to lead to evacuation. The location of the victims at the time of the eruptions seemed to be the most critical determinant of survival. What medical care could do at this point was very limited. No rescuers died, but some suffered acute mountain sickness and hypothermia. In the following year, education for rescue organizations began, and volcano information was released to the public in real-time as raw data, regardless of whether they could be understood. In 2022, shelters were constructed near the summit of Mt. Ontake.Conclusion:A severe volcanic eruption leaves little time for people to evacuate, and emergency medical care can play only a minor role. In Japan, where there are many volcanoes, measures are underway to support self-help to increase the possibility of saving lives for climbers and rescuers in an eruption that is difficult to predict.

Semantic segmentation of explosive volcanic plumes through deep learning

Tracking explosive volcanic phenomena can provide important information for hazard monitoring and volcano research. Perhaps the simplest forms of monitoring instruments are visible-wavelength cameras, which are routinely deployed on volcanoes around the globe. Here, we present the development of deep learning models, based on convolutional neural networks (CNNs), to perform semantic segmentation of explosive volcanic plumes on visible imagery, therefore classifying each pixel of an image as either explosive plume or not explosive plume. We have developed 3 models, each with average validation accuracies of >97% under 10-fold cross-validation; although we do highlight that, due to the limited training and validation dataset, this value is likely an overestimate of real-world performance. We then present model deployment for automated retrieval of plume height, rise speed and propagation direction, all parameters which can have great utility particularly in ash dispersion modelling and associated aviation hazard identification. The 3 trained models are freely available for download at https://doi.org/10.15131/shef.data.17061509.

Special Issue on Future Volcano Research in Japan: Integrated Program for Next-Generation Volcano Research

Since Japan has 111 active volcanoes, we living there need to be prepared for the volcanic disasters that we will likely encounter in our lifetime. The Integrated Program for Next Generation Volcano Research and Human Resource Development (INeVRH), a research project of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), started in 2016 and is now in its 7th year. It is approaching its final stage will be ready to make proposals that will improve our knowledge from both scientific and practical points of view. In theme A, the Japan Volcanic Data Network (JVDN) system started its function as a volcanic research platform, providing the observation and analysis data of many universities, governmental agencies, and institutes. The JVDN system promotes collaborative, multidisciplinary study. In theme B, many strategic observation techniques now deployed have revealed the characteristics of volcanoes in detail. For example, a dense seismic and magnetic survey has clarified the fine structure of the hydrothermal system beneath volcanoes, providing information that can be used to evaluate their phreatic eruption potential. In addition, brand-new volcanic gas observation techniques using drones now obtain in-situ information effectively. Theme C has obtained geologic and petrologic findings at many volcanoes and has come to the stage in which systematic compilation of this database would be useful to comparative studies of many volcanoes. These findings are also used in numerical simulations that combine geologic, petrologic, and geophysical formulations to produce more comprehensive models used to interpret volcanic activity. Theme D focuses on the development of practical technologies for volcanic disaster mitigation, mainly related to volcanic ash. A scheme for the quick detection and evaluation of volcanic ash is proposed through observation and numerical simulation, and an experiment is performed to reveal the thickness threshold of volcanic ash deposits on air-conditioners. This special issue reports on some up-to-date topics that could become the basis of dynamic and effective links between themes A, B, C, and D, which may serve as a base and direction for discussions that summarize and conclude this 10-year project.

Development of Portable SAR for Detection of Volcano Deformation: Application of SAR Interferometry to the Repeated Observation Data

Synthetic aperture radar (SAR), which transmits radar waves from the ground, can detect crustal deformation with high spatial and temporal resolution. To obtain crustal deformation data useful for evaluating volcanic activity, we are developing a portable SAR that can conduct repeated observations without being fixed to the site under Project B of the Integrated Program for Next Generation Volcano Research and Human Resource Development. We named this SAR sensor: SAR for crustal deformation with portable equipment (SCOPE). SCOPE detects crustal deformation over a wide area by repeating observations at several points, which differs from the general ground-based SAR (GB-SAR). SCOPE has four observation types: GB-SAR, car-borne SAR, cart-borne SAR, and man-borne SAR, which are used to conduct such mobile observations efficiently. This study performed repeated observations with a 1-day interval using GB-SAR and car-borne SAR and obtained high coherence and reasonable phase distribution. When using the man-borne SAR type, moderate coherence was obtained. However, focusing on the SAR image was insufficient, and an inappropriate phase slope appeared in the interferogram, suggesting that improvements in the observation and analysis methods remained. We also investigated the temporal persistence of coherence when applying SAR interferometry to the SCOPE data. Sufficient coherence was obtained to detect crustal deformation in sparsely vegetated areas for a data pair at a 1-year interval. Even in densely vegetated areas, sufficient coherence was obtained from the data pair at intervals of several months. These results show that SCOPE has high potential for detecting crustal deformation based on repeated observations.

Reviewing volcano hazard and risk communications in Ecuador: experiences from a fast-format workshop

Hazard and risk communication requires the design and dissemination of clear messages that enhance people’s actions before, during, and after volcanic crises. To create effective messages, the communication components such as message format and content, must be considered. Changes in technology are changing the way people communicate at an ever-increasing pace; thus, we propose revising the basic components of the communication process to improve the dialogue between scientists and the public. We describe communication issues during and outside volcanic crises in Ecuador and assess possible causes and consequences. These ideas were discussed during the short-duration “Volcano Geophysical Principles and Hazards Communications” Workshop in Baños, Ecuador in 2019. We review and propose communication strategies for volcanic hazards and risks that resulted from the workshop discussions and experiences of experts from the Instituto Geofísico (IG-EPN), local and international professors involved in volcano research and communication, and students from universities across Ecuador.

A multi-purpose, multi-rotor drone system for long-range and high-altitude volcanic gas plume measurements

Abstract. A multi-rotor drone has been adapted for studies of volcanic gas plumes. This adaptation includes improved capacity for high-altitude and long-range, real-time SO2 concentration monitoring, long-range manual control, remotely activated bag sampling and plume speed measurement capability. The drone is capable of acting as a stable platform for various instrument configurations, including multi-component gas analysis system (MultiGAS) instruments for in situ measurements of SO2, H2S, and CO2 concentrations in the gas plume and portable differential optical absorption spectrometer (MobileDOAS) instruments for spectroscopic measurement of total SO2 emission rate, remotely controlled gas sampling in bags and sampling with gas denuders for posterior analysis on the ground of isotopic composition and halogens. The platform we present was field-tested during three campaigns in Papua New Guinea: in 2016 at Tavurvur, Bagana and Ulawun volcanoes, in 2018 at Tavurvur and Langila volcanoes and in 2019 at Tavurvur and Manam volcanoes, as well as in Mt. Etna in Italy in 2017. This paper describes the drone platform and the multiple payloads, the various measurement strategies and an algorithm to correct for different response times of MultiGAS sensors. Specifically, we emphasize the need for an adaptive flight path, together with live data transmission of a plume tracer (such as SO2 concentration) to the ground station, to ensure optimal plume interception when operating beyond the visual line of sight. We present results from a comprehensive plume characterization obtained during a field deployment at Manam volcano in May 2019. The Papua New Guinea region, and particularly Manam volcano, has not been extensively studied for volcanic gases due to its remote location, inaccessible summit region and high level of volcanic activity. We demonstrate that the combination of a multi-rotor drone with modular payloads is a versatile solution to obtain the flux and composition of volcanic plumes, even for the case of a highly active volcano with a high-altitude plume such as Manam. Drone-based measurements offer a valuable solution to volcano research and monitoring applications and provide an alternative and complementary method to ground-based and direct sampling of volcanic gases.

Volcano Project Design: Innovation In Geoscience Learning

The research aim was to develop the Volcano Project Design (VPD) for improving the physics student research skills about volcano. The method used is a qualitative analysis where the research sample involves 34 undergraduate of physics students. The instrument used in VPD was equipped with the assessment format and rubric that was developed by researchers. The instruments tools were validated by experts in the field of geoscience and volcanology. The VPD guide contains the theoretical basis of fieldwork, descriptions of activities, project themes and targets to be achieved, phases of activities, and assessment of activities in the field. In addition, in the guidelines is also equipped with a guide of proposal preparation, field report and research products. The important results showed that the physics students were succeeded in conducting volcano research using VPD. This result was supported by the capabilities to identifying some crucial problems about volcanoes, presenting some solution based on several issues that have been identified and providing an accurate explanation of volcanic phenomena. The interesting finding based on research is the students’ research product as new information in geoscience. Even though needs intensive guidance, the product has an opportunity to be published broadly. Based on students’ perception, the program succeeded to build students' scientific attitude, constructing a positive value to the environment around the volcano and perfectly prepare students to help the community in the face of volcanic disasters.

Presenting the Sixth JDR Award

It is our great pleasures to present the sixth JDR Award to Prof. Masato Iguchi. Prof. Iguchi, as the top guest editor, published two JDR special issues entitled “Integrated Study on Mitigation of Multimodal disasters caused by Ejection of Volcanic Products.” These special issues, vol.11, no.1 in 2016 and vol.14, no.1 in 2019, were results of a project (2013–2018) of the Science and Technology Research Partnership for Sustainable Development (SATREPS). The second special issue set a record for the highest annual download. In addition, he was the first author or co-author of 11 papers published by JDR in 2019. Professor Iguchi, as one of most recognized volcanologists in the world, has been leading observation research of active volcanoes as the Director of the Sakurajima Volcano Research Center of Kyoto University’s Disaster Prevention Research Institute. He has promoted geophysical research on volcanic activity not only in Japan but also in Indonesia, evaluating volcanic activity by incorporating the results of material science and demonstrating the effectiveness of long-term, multi-item observations in those processes. He has made a significant contribution to the promotion of Indonesian volcano research, taking over the strong will of former Kyoto University professors, and his contributions have culminated in the aforementioned two special issues. On behalf of the JDR editorial board, I wish to thank Prof. Iguchi for his efforts and to congratulate him as the winner of the sixth JDR Award.

PUFF Model Prediction of Volcanic Ash Plume Dispersal for Sakurajima Using MP Radar Observation

In this study, a real-time volcanic ash plume prediction by the PUFF system was applied to the Sakurajima volcano (which erupted at 17:24 Japan Standard Time (JST) on 8 November 2019), using the direct observation of the multi-parameter (MP) radar data installed at the Sakurajima Volcano Research Center. The MP radar showed a plume height of 5500 m a.s.l. around the volcano. The height was higher than the 4000 m by the PUFF system, but was lower than the observational report of 6500 m by the Japan Meteorological Agency in Kagoshima. In this study, ash particles by the MP radar observation were assimilated to the running PUFF system operated by the real-time emission rate and plume height, since the radar provides accurate plume height. According to the simulation results, the model prediction has been improved in the shape of the ash cloud with accurate plume top by the new MP radar observation. The plume top is corrected from 4000 m to 5500 m a.s.l., and the three-dimensional (3D) ash dispersal agrees with the observation. It was demonstrated by this study that the direct observation of MP radar obviously improved the model prediction, and enhanced the reliability of the prediction model.

POLA PERUBAHAN HARIAN SUHU AIR DAN KECEPATAN ARUS DI SEKITAR GUNUNG API BAWAH LAUT MAHENGETANG


 
 
 
 Indonesia an archipelago with 70% of the territorial waters stretching from the western end of Sumatra Island to the east of the Papua region, with the characteristic of the vast ocean of underwater structures in the Indonesian archipelago is also important to be discussed deeper. For that the underwater volcano research is very rare. This undersea research has been implemented and is a collaborative research study with DRPM's beginner lecturer SCHEME research with the title of Master of Umbrella research "The analysis and modeling of Temporal changes and partial fraction of the sea water temperature at the Mahengetang underwater volcano". Involving 3 UNIMA students. The expedition was held from 20 to 22 March 2019. Where one of the objectives of this research is to obtain the data on water temperature fluctuations and the current speed of the underwater volcano Mahengetang has shown the pattern of water temperature and the current velocity of sea water from the upstream and downstream transect. From the results of analysis and modeling showed that the hydrodynamics factor and geothermal energy. The results of the hydrodynamics analysis indicate that the current velocity relies on tidal activity. The results of analysis and modeling show that water temperature varies horizontally and vertically. The velocity of currents and the masses of warm water are associated with the pattern of spatial distribution of coral reefs. The results of this PHISYCS analysis became a reference to the content of water chemicals, and biotic components such as coral reefs and various biota that live in it.
 
 
 

A New Japan Volcanological Database

For the purpose of the development of volcanology and practical application to volcanic hazard mitigation, we are conducting a new project named the Integrated Program for Next Generation Volcano Research and Human Resources Development (INeVRH). This project consists of 4 themes focusing on observation, forecasting, countermeasures and data sharing system. Data sharing system is named the Japan Volcanological Data Network (JVDN), which will be a platform to combine observation, prediction and countermeasure data to give information for the judgement at branch nodes of event tree for volcanic crises.

Practising an explosive eruption in Iceland: outcomes from a European exercise

A 3 day exercise simulating unrest and a large explosive eruption at Katla volcano, Iceland, was conducted in January 2016. A large volume of simulated data based on a complex, but realistic eruption scenario was compiled in advance and then transmitted to exercise participants in near-real time over the course of the exercise. The scenario was designed to test the expertise and procedures of the local institutions in charge of warning and responding to volcanic hazards, namely the volcano observatory, national civil protection, and the local university-science sector, as well as their interactions with the European science community and the London Volcanic Ash Advisory Centre. This exercise was the first of this magnitude and scope in Iceland and has revealed many successful developments introduced since the 2010 Eyjafjallajökull and 2011 Grímsvötn eruptions. Following the exercise, 90% of participants said that they felt better prepared for a future eruption. As with any exercise, it also identified areas where further development is required and improvements can be made to procedures. Seven key recommendations are made to further develop capability and enhance the collaboration between the volcano observatory, volcano research institutions and civil protection authorities. These recommendations cover topics including notification of responders, authoritative messaging, data sharing and media interaction, and are more broadly applicable to volcanic institutions elsewhere. Lessons and suggestions for how to run a large-scale volcanic exercise are given and could be adopted by those planning to rehearse their own response procedures.

Development of an Optical Multispectral Remote Sensing System for Measuring Volcanic Surface Phenomena – Promotion Project for Next Generation Volcano Research B2 (Subtopic 2-2)

In 2016, we launched the “Promotion Project for Next Generation Volcano Research B2 (Theme B: Development of Cutting-edge Volcano Observation Technology, subtheme 2: Development of Remote Sensing Techniques for Volcano Observation), subtopic 2-2 (Development of Remote Sensing Techniques for Surface Phenomena of Volcano)” under the “Integrated Program for Next Generation Volcano Research and Human Resources Development” [1], aiming at the development of an optical multispectral remote sensing system for measuring volcanic surface phenomena. With subtopic 2-2, we are planning to develop a new observation device called a surface phenomena imaging camera (SPIC), which is technically superior to current remote sensing techniques, i.e., optical remote observation techniques used to observe volcanic surface phenomena from aircrafts or ground. We are also aiming at applying the developed observation system to quantify volcanic activities and determine volcanic eruption potentials (degrees of urgency) or branching of event trees for volcanic crises with high accuracy, contributing to better predictions of volcanic eruption transitions. To achieve the above-mentioned aims, we started the development of the SPIC by equipping it with camera-type sensors, based on preliminary analyses of the experimental observations made with the airborne spectral imaging system ARTS-SE, which consists of a pushbroom scanner and a camera system, developed by the National Research Institute for Earth Science and Disaster Resilience in FY 2015. We have already developed its components, such as the prototype filter-type multiband cameras SPIC-UC, a prototype uncooled infrared camera, SPIC-C, a cooled camera, and SPIC-SS, a visible-light camera. The SPIC-UC is a two-band camera with the function of visualizing temperature and SO2 gas concentration distributions. The SPIC-C has the function of measuring temperatures between 2 and 1075◦C with high accuracy (noise equivalent temperature difference, NETD: 16 mK); it is equipped with a sensor and a filter wheel that work in the middle wave infrared region (MWIR). The SPIC-SS is a six-lens multiband camera system that estimates the measured images from multiband spectra (6 bands) to hyper spectra (300 bands). Further, we studied a method to estimate digital surface model with a ∼30-m error. As our plan has progressed as scheduled, we intend to complete the prototype SPIC by 2020.

Database of Crustal Deformation Observed by SAR: Improving Atmospheric Delay Mitigation for Satellite SAR Interferometry and Developing L-Band Multi-Type Portable SAR

Spaceborne synthetic aperture radar (SAR) and ground-based radar interferometers (GBRIs) can be used to detect spatially detailed crustal deformations that are difficult to detect by on-site observations, the Global Navigation Satellite System, tiltmeters, and so on. To make such crustal deformation information readily available to those engaged in evaluating volcanic activities and researching the mechanisms, we are preparing a database within the Japan Volcanological Data Network data sharing system to store crustal deformation detected by spaceborne SAR and GBRIs (Subtheme 2-1, Project B, the Integrated Program for Next Generation Volcano Research and Human Resource Development). In this study, we examined methods to reduce atmospheric delay noise in SAR interferometry using the numerical weather model and determined the methods for resampling the analytical values of the numerical weather model and estimating atmospheric delay to efficiently determine atmospheric delay. We show that the atmospheric delay can be estimated with higher accuracy by properly combining the isobaric surface and ground surface data of the mesoscale model (MSM) provided by the Japan Meteorological Agency. We are developing a multi-type portable SAR system as a GBRI system such that it would allow campaign observations whenever increased volcanic activities are observed and acquire crustal deformation with a higher temporal resolution than spaceborne SAR for storage in the database. This system employs L-band radar, which has a higher penetrability against vegetation. Two modes of observations are possible: ground-based SAR and car-borne SAR. The prototype was fabricated to conduct experiments necessary to develop a working model. The experimental observations was carried out around Asama volcano, and we confirmed that clear fringe was obtained.

Development and Publication of Volcanic Base Map Data

Abstract. Japan has 111 active volcanoes accounting for about 7 percent of active volcanoes in the world and many volcanic disasters have been recorded so far. Geospatial Information Authority of Japan (GSI) proceeds to develop Volcanic Base Map, which depicts specific landforms of volcanoes precisely from 1979 to 2009 for the purpose of providing basic information for formulating various types of volcanic disaster prevention plans and volcano research. Although Volcanic Base Maps have been created by aerial photogrammetry for 31 active volcanoes throughout Japan as a paper map with a scale of 1:2,500 to 1:10,000, they have not been able to meet the needs of recent volcanic disaster prevention measures and have not been fully utilized in disaster emergency measures due to the following reasons: (1) There are undeveloped volcanoes because creation pace was limited for one volcano per year in the conventional creation method; (2) Considerable number of years has passed after its maintenance, so the latest terrain and infrastructure have not been updated; (3) It is impossible to cover the whole area of the volcano and the range of damage estimation because the development around the crater is mainly focused; (4) Basic information such as disaster prevention related facility information, which is necessary for the formulating volcanic disaster prevention plan and disaster emergency measures, has not been covered; (5) Since they were provided by a paper map for a fee, they were not suitable for advanced application using GIS.In order to solve the above issues and to promptly develop and provide maps of volcanoes, we have revised methods of making and acquisition criteria and have newly created Volcanic Base Map Data from 2017. Contour line data was created using digital stereoscopic machine in the conventional method of Volcanic Base Map, but it was changed to generate automatically by Digital Elevation Model of airborne laser survey. Also, we have changed to create features such as roads, buildings and disaster prevention-related facilities by using existing geospatial data maintained by GSI and materials collected from relevant organs. Therefore, the process of numerical mapping and associated photocontrol points surveying, pricking and aerial triangulation becomes omissible, and the number of creating maps can be increased. Although some of the designated evacuation shelters and heliports are not acquired in the conventional Volcanic Base Map, they are added as an acquisition item in Volcanic Base Map Data in order to make it easier to utilize to disaster prevention plan and emergency measures.Volcanic Base Map Data consists of three types of raster image data (base map, colour relief map and photomap, Figure 1), two types of vector data (Shapefile and Digital Mapping data) and GSI Tile data, is started to provide and publish on March 31, 2017 on the website of GSI and 14 volcanoes are provided as of October 2018. While Volcanic Base Map Data is possible to update in a very short time compared to conventional paper maps by maintaining and creating as numerical data, if there is a change in the contents of display such as disaster prevention related facilities and important infrastructures, it is necessary to consider a mechanism that can quickly update and publish maps. Furthermore, it is necessary to promote the products in each of the Volcano Disaster Management Councils and to continuously grasp the needs of users to be utilized more in the future.

Development of a Data Sharing System for Japan Volcanological Data Network

In Japan, a number of universities, research institutes, and administrative organizations continue to conduct observations on volcanoes according to their respective roles. They also promote the distribution and sharing of observation data and have collaborated with each other. Japan Volcanological Data Network (JVDN) is a framework that strengthens this cooperation, promotes volcano research, and contributes to volcanic disaster mitigation. In this paper, we report the overview, progress, tasks, and future prospects of the system being developed for JVDN that was initiated in 2016. The observational data collected from each organization is stored in a database and shared using visualization tools to promote collaborative research, (e.g., multi-disciplinary research for eruption prediction) and cooperation between organizations. Furthermore, this database will contribute to volcanic disaster mitigation measures through collaboration between the volcano research community and administrative organizations responsible for volcanic crisis management. Adaptation to the standards of the international WOVOdat database will also promote cooperation with research institutes worldwide.

Special Issue on Integrated Program for Next Generation Volcano Research and Human Resource Development

The phreatic eruption of the Ontake volcano in 2014 reminded us that even moderately active volcanoes, most of which are tourist attractions in Japan, can sometimes exhibit unpredictable and hazardous behaviors, taking away the lives of those who do not fully recognize their threat. With this adding momentum, the Japanese people want volcanology and its applications to be developed to further improve the precision of volcanic eruption alerts. To meet this expectation, a comprehensive program, the “Integrated program for next-generation volcano research and human resource development,” sponsored by the Ministry of Education, Culture, Sports, Science and Technology, was started in November 2016 on a 10-years plan. The most stunning aspect of this program is the integration of (1) a research project and (2) a human resource development program to mitigate volcanic disasters in Japan from long-term point of view. Both of these are collaboratively supported by many researchers from almost all Japanese universities and national institutions related to volcanology. This special issue compiles several topics in this research project to demonstrate its present stage of development and to indicate its anticipated future destination. The target of the research project is to develop, using multi-disciplinary scientific methods, new ways of evaluating volcanic hazards. Specifically, four research groups jointly (A) construct a data archive and exchange system connecting all Japanese volcanologists, (B) develop new geophysical and geochemical observation techniques and methods of analyzing data, (C) evolve methods of predicting volcanic eruptions based on eruption history from precise geological survey and numerical simulations, and (D) propose the provision of technologies for volcanic disasters. We hope that this program will greatly help to mitigate volcanic disasters in Japan, and we will strive to realize this through the research project.

Conveying Volcano Information Effectively to Stakeholders – A New Project for Promotion of Next Generation Volcano Research

A new program for the Next Generation Volcano Research and Human Resource Development started in 2016, following the government’s analysis of a volcanic disaster at Mount Ontake in 2014. One of its important purposes is the development of a technology that can provide visualized information of imminent volcanic hazards to the stakeholders. The latter include researchers in the Volcano Disaster Prevention Councils. Since the volcanic activity in Japan has been relatively less in the past few hundred years, larger eruptions are certainly expected to occur in the near future. Volcanic risk management has developed in Japan independently of university or institutional research, and by a national law, researchers are not allowed to officially forecast imminent volcanic eruptions. In the case of large eruptions never being observed, a close communication between the Japan Meteorological Agency and researchers becomes very important. Our project goal is issuing effective information on real-time observational and hazard mitigation simulation data to the stakeholders and researchers. Based on our inspection and interviews we develop information tools using which the above data are provided effectively and the dissemination and education of volcanic disasters are performed.

Space-Based Imaging Radar Studies of U.S. Volcanoes

The arrival of space-based imaging radar as a revolutionary land-surface mapping and monitoring tool little more than a quarter century ago enabled a spate of innovative volcano research worldwide. Soon after launch of European Space Agency’s ERS-1 spacecraft in 1991, the U.S. Geological Survey began SAR and InSAR studies of volcanoes in the Aleutian and Cascades arcs, in Hawaiʻi, and elsewhere in the western U.S. including the Yellowstone and Long Valley calderas. This paper summarizes results of that effort and presents new findings concerning: (1) prevalence of volcano deformation in the Aleutian and Cascade arcs; (2) surface-change detection and hazard assessment during eruptions at Aleutian and Hawaiian volcanoes; (3) geodetic imaging of magma storage and transport systems in Hawaiʻi; and (4) deformation sources and processes at the Yellowstone and Long Valley calderas. Surface deformation caused by a variety of processes is common in arc settings and could easily escape detection without systematic InSAR surveillance. Space-based SAR imaging of active lava flows and domes in remote or heavily vegetated settings, including during periods of bad weather and darkness, extends land-based monitoring capabilities and improves hazards assessments. At Kīlauea Volcano, comprehensive SAR and InSAR observations identify multiple magma storage zones beneath the summit area and along the East Rift Zone, and illuminate magma transport pathways. The same approach at Yellowstone tracks the ascent of magmatic volatiles from a mid-crustal intrusion to shallow depth and relates that process to increased hydrothermal activity at the surface. Together with recent and planned launches of highly capable imaging-radar satellites, these findings support an optimistic outlook for near-real time surveillance of volcanoes at global scale in the coming decade.