Miyagi Prefecture Research Articles

Online Information as Real-Time Big Data About Heavy Rain Disasters and its Limitations: Case Study of Miyagi Prefecture, Japan, During Typhoons 17 and 18 in 2015

The role of public online information in helping to reduce disaster damage is expected to become increasingly important since it can be used for decision making about disaster response. This paper aims to discuss the effectiveness and limitations of real-time online information about heavy rainfall based on an analysis of data on the disaster caused by Typhoons 17 and 18 in 2015 in Miyagi prefecture, Japan, and on a focus group interview survey with four experts on natural disasters. The results from the interviews showed the following: (1) Landslide alert information is reliable for prediction purposes. However, many people did not monitor it because it was released around midnight. (2) Areas of landslide occurrence and river flooding correspond to areas with heavy cumulative rainfall. Yet cumulative rainfall data are not available on the web. (3) The available radar-rainfall data can be used to predict the situation one hour from the present as long as the person has expert knowledge. (4) It is possible to monitor river water levels at many points. Yet, about half of the observation points have no established “flood danger water level.” (5) Local governments released a great amount of disaster information through social media before flooding occurred on some rivers. However, one must monitor multiple social media accounts and not just the account of one’s hometown.

Verification of a Method for Estimating Building Damage in Extensive Tsunami Affected Areas Using L-Band SAR Data

Remote sensing technology is effective for identifying the Remote sensing technology is effective for identifying the extensive damage caused by tsunami disasters. Many methods have been developed to detect building damage at the building unit scale. Of these methods, X-band Synthetic Aperture Radar (SAR) data has a high resolution and is useful to investigate the detailed conditions on the Earth’s surface, although its spatial coverage is relatively small. In contrast, L-band SAR data has a lower resolution, leading to difficulties detecting building damage, although it can cover a broad area. During disasters, it is important to understand the damage across extensive areas in a short time; therefore, it is necessary to develop a method with broad coverage with high accuracy. The primary objective of this study is to develop a method to estimate building damage in tsunami affected areas using L-band SAR (ALOS/PALSAR) data. We developed our method by extending a previously proposed method for X-band SAR (TerraSAR-X) data. This study focused on Sendai City and Watari town in Miyagi Prefecture, where many houses were washed away during the 2011 Tohoku earthquake and tsunami. We verified that the function we developed produced good performance in estimating the number of washed-away buildings, corresponding with ground truth data with a Pearson correlation coefficient of 0.97. Verification was conducted in another study area, which yielded a Pearson correlation coefficient of 0.87.

Ciliate Protozoa from the Rumens of Japanese Serows (Capricornis crispus) Captured in the Northern Part of Shizuoka Prefecture, Japan

Ciliate fauna collected from the rumens of eight wild Japanese serows (Capricornis crispus) captured in the northern part of Shizuoka Prefecture, Japan, were compared with the ciliate faunas found in other Japanese wild ruminants. We identified six species belonging to two genera of ciliates (Entodinium nanellum, Ent. minimum, Ent. simplex, Ent. dubardi, Ent. longinucleatum, and Elytroplastron bubali), all of which had been reported in a previous study examining the rumen contents of Japanese serows in Gifu and Miyagi Prefectures. However, four of the previously identified ciliate species (Dasytricha ruminantium, Ent. lobosospinosum, Ent. ekendrae, and Epidinium ecaudatum) were not detected in this study. Ely. bubali was detected frequently, suggesting that this species is characteristic of the rumen of Japanese serows. Furthermore, the six ciliate species in this study were observed in over 70% of the studied serows, suggesting that these ciliate species are widely distributed in the rumens of serows in this study area.

The association between coffee consumption and bladder cancer incidence in a pooled analysis of the Miyagi Cohort Study and Ohsaki Cohort Study.

Recent epidemiological studies of the association between coffee consumption and the risk of bladder cancer have yielded conflicting results. The aim of the present study was to examine the association between coffee consumption and the incidence of bladder cancer on the basis of pooled data from two cohort studies carried out in Miyagi Prefecture, northeastern Japan. We delivered self-administered questionnaires inquiring about the frequency of coffee consumption and other lifestyle factors in 1990 for the Miyagi Cohort Study and in 1994 for the Ohsaki Cohort Study. We followed 73 346 individuals from both cohorts and identified 274 cases of bladder cancer during 17.6 years for the Miyagi Cohort Study and 13.3 years for the Ohsaki Cohort Study. The multivariate-adjusted hazard ratios (95% confidence intervals) of bladder cancer incidence for the individuals who drank coffee occasionally, 1-2 cups/day, and 3 or more cups/day compared with never drinkers were 1.22 (0.90-1.66), 0.88 (0.61-1.26), and 0.56 (0.32-0.99), respectively (Ptrend=0.04). The inverse association remained even after stratification for smoking status. These data indicate that there is a significant inverse association between coffee consumption and the risk of bladder cancer.

オーラル・アプローチ再評価試論 : 戦後英語教育史の一環としての山家保氏の宮城県に於ける実践研究指導

オーラル・アプローチ再評価試論 : 戦後英語教育史の一環としての山家保氏の宮城県に於ける実践研究指導

Radiocesium contamination of aquatic organisms in the estuary of the Abukuma River flowing through Fukushima

AbstractIn the summer of 2013, we measured the radiocesium (134Cs and 137Cs) concentrations in aquatic organisms inhabiting the estuary of the Abukuma River, which flows through the Fukushima and Miyagi Prefectures. Radiocesium concentrations in four muscle‐tissue samples of blackhead seabream (Acanthopagrus schlegeli) [1240, 914, 202 and 106 Bq kg−1 wet weight (w.w.)] and two whole‐body samples deriving from multiple individuals of flathead grey mullet (Mugil cephalus) (129 and 110 Bq kg−1 w.w.) exceeded the Japanese standard limit for radiocesium levels in foods (100 Bq kg−1 w.w.). However, radiocesium concentrations in the other fish samples were lower than the Japanese standard limit. In addition, radiocesium concentrations in crustaceans, major prey items of omnivorous and carnivorous fish species in the Abukuma River estuary, were generally low (0.444–15.1 Bq kg−1 w.w.). Stable isotope analysis indicated that the feeding habit of the three heavily contaminated blackhead seabream, which the radiocesium concentrations were about several times or more higher than the Japanese standard limit, were similar to those of other individuals collected from the same sampling site. Therefore, the difference in the radiocesium level between the three heavily contaminated individuals and the less‐contaminated individuals of blackhead seabream was not because of a recent feeding habit in the Abukuma River estuary. Environmental conditions in the Abukuma River estuary in the summer of 2013 would not have had the potential to increase radiocesium concentrations in the muscle tissues of fish inhabiting the estuary to levels greater than 100 Bq kg−1 w.w.

P16 栗駒火山南麓に分布する火砕堆積物 : 小野田層の層序,岩石学的特徴およびK-Ar年代(ポスターセッション)

P16 栗駒火山南麓に分布する火砕堆積物 : 小野田層の層序,岩石学的特徴およびK-Ar年代(ポスターセッション)

Effects of salt water immersion caused by a tsunami on δ13C and δ18O values of Pinus thunbergii tree‐ring cellulose

AbstractPinus thunbergii trees growing on Pacific coastal sand dunes in Japan were immersed by the tsunami that followed the Great East Japan Earthquake on 11 March 2011. Even trees that survived direct physical damage began to die during the following summer, probably because of the physiological stress of salt water immersion. The objectives of this study were to analyze the relationship between the carbon and oxygen isotope values (δ13C and δ18O, respectively) of P. thunbergii tree‐ring cellulose and the effects of salt water immersion caused by the tsunami. Pinus thunbergii trees were sampled in Yamamoto, Miyagi Prefecture, and in Misawa, Aomori Prefecture. Each tree‐ring that formed between 2008 and 2012 was sliced into four to eight equal subdivisions, and the isotope values were analyzed at a high time‐scale resolution. Tree rings that were immersed in seawater from the tsunami had higher δ13C values in the earlywood that formed in the spring following the tsunami than those formed prior to the disaster. This increase in δ13C values was likely caused by osmotic stress from root immersion in salt water. We did not observe a clear change in tree‐ring δ18O values after the tsunami. This lack of variance might have resulted from the post‐photosynthetic exchange of carbonyl oxygens with non‐18O‐enriched xylem water.

Evaluation of a method for removing cesium and reducing the volume of leaf litter from broad-leaved trees contaminated by the Fukushima Daiichi nuclear accident during the Great East Japan Earthquake

The town of Marumori in southern Miyagi Prefecture borders on Fukushima Prefecture, and following the accident at the Fukushima Daiichi nuclear power plant, there were concerns about cesium deposition in forested areas. One of the authors of this paper has continually surveyed leaf litter from the forested areas. As leaf litter may be a source of cesium contamination from the forest to downstream areas, we considered a simplified version of wet oxidation, a method previously presented by one of the authors of this study, as a technology to reduce leaf litter weight and cesium concentration, separating radioactive nuclides from non-radioactive ones, in leaf litter. We tested our method in three experiments. Experiment 1 used new leaf litter (232 Bq/kg) from the surface of a small stream at the forest edge nearby an area with air dose level higher than the national standard threshold of 0.23 μSv/h for the implementation of governmental decontamination works. Experiment 2 applied wet oxidation to older leaf litter (705 Bq/kg) harvested from a pasture nearby the stream mentioned above. We also used the same leaf litter in experiment 3 for a cesium release tests using pure water. In experiment 1 and 2 we treated leaf litter with a sodium hypochlorite solution, optimizing sodium hypochlorite concentration and reaction temperature. We measured a 50–60% decrease in the leaf litter weight and a 60% decrease in the cesium concentration. Moreover, we also measured the amount of cesium washout. The cesium budget of experiment 1 showed no cesium gasification (wet oxidation avoids airborne cesium as this element is prone to be volatile at 600 °C), and that high sodium hypochlorite concentration and high temperature had a strong positive effect on leaf litter volume reduction and cesium decontamination. Experiment 2 confirmed the reproducibility of these results in leaves with different cesium concentration and harvested in different conditions. We could also explain the mechanism behind leaf litter weight and cesium concentration reduction. Experiment 3 helped us to investigate the effects of the matter present on the surface of the water and the contribution of water soluble cesium. Concurrent experiments on changes in leaf litter chemical composition confirmed that our modified wet oxidation method had an effect on the removal of acid-insoluble lignin. Removal of lignin, a refractory component, might allow for a better utilization of the residue left after implementation of the proposed simplified wet oxidation. Thus, real wastes could be smaller than the residues. Together with the observed smaller cesium concentration in the residue, the proposed method in this study is expected to contribute to mitigate the risk due to the fallen leaves containing cesium.

The role of a local newspaper after disaster: an intrinsic case study of Ishinomaki, Japan

ABSTRACTThe city of Ishinomaki in Miyagi prefecture was devastated by the tsunami that struck Japan’s North East Coast on 11 March 2011. Drawing on fieldwork conducted in Ishinomaki, which included interviews with senior journalists from the city’s two local newspapers, the Ishinomaki Hibi Shimbun and the Ishinomaki Kahoku, this paper presents an intrinsic case study of the role a local newspaper in Ishinomaki after the Great East Japan Disaster. The evidence reveals that in the immediate aftermath of the tsunami journalists recognised how their newspaper could serve the immediate information-needs of the local community by providing essential lifeline information, describing a duty to report, despite the operational difficulties that their newspapers faced. In the longer term recovery phase, interviewees acknowledged how their newspapers have attempted to communicate a message of hope to the city and provide an alternative perspective to the national media, which sometimes gave a false impression of the state of Ishinomaki’s recovery. This paper offers some insights into journalistic role conceptions, illustrating how journalists from the two newspapers embraced the role of information-disseminator after the disaster, and also identifies avenues for further research.

The 2016 Fukushima earthquake and tsunami: Local tsunami behavior and recommendations for tsunami disaster risk reduction

The 2016 Fukushima earthquake and tsunami presented several new issues of tsunami generation mechanism and propagation, as well as of organizational responses such as evacuation procedures and dissemination of tsunami warning. This study focuses on explanations to issues of public interest based on the experiences during the 2016 tsunami: (1) Despite Fukushima Prefecture's proximity to the earthquake's epicenter, why was the largest wave observed in the neighboring Miyagi Prefecture? (2) Why was the second wave of the tsunami larger than the first? (3) Why was the tsunami advisory elevated to a tsunami warning in Miyagi Prefecture? (4) Why did tsunami intrusions into rivers occur? (5) And why were local tsunami runup values much higher than the broadcasted tsunami amplitudes from local tide gauges? In the wake of the 2011 Great East Japan earthquake and tsunami, this study also points out remaining problems and new perspectives related to tsunami disaster risk reduction. These include tsunami warnings and advisories by emergency management agencies, the fact that tsunami waves are higher near the coast than in the open ocean, and refraining from being close to rivers in case of a tsunami. Based to Japan's experiences with disaster mitigation, lessons were learned from numerous events that could lead to revisions and improvements of current warning systems and provide useful guidelines for other countries.

Longitudinal changes in body mass index of children affected by the Great East Japan Earthquake.

The evacuation and disruption in housing caused by the 2011 Great East Japan Earthquake and following nuclear radiation may have influenced child health in many respects. However, studies regarding longitudinal childhood growth are limited. Therefore, in this study we aimed to explore the influence of the earthquake on longitudinal changes in body mass index in preschool children. Participants were children from nursery schools who cooperated with the study in the Iwate, Miyagi and Fukushima prefectures. The exposed group consisted of children who experienced the earthquake during their preschool-age period (4-5 years old). The historical control group included children who were born 2 years earlier than the exposed children in the same prefectures. Trajectories regarding body mass index and prevalence of overweight/obesity were compared between the two groups using multilevel analysis. Differences in the changes in BMI between before and after the earthquake, and proportion of overweight/obesity was compared between the two groups. We also conducted subgroup analysis by defining children with specific personal disaster experiences within the exposed group. A total of 9722 children were included in the study. Children in the exposed group had higher body mass indices and a higher proportion of overweight after the earthquake than the control group. These differences were more obvious when confined to exposed children with specific personal disaster experiences. Children's growth and development-related health issues such as increased BMI after natural disasters should evoke great attention.

Pregnant Women's Awareness of Social Capital in the Great East Japan Earthquake-Affected Areas of Miyagi Prefecture: The Japan Environment and Children's Study.

We aimed to clarify the correlation between the 2011 Great East Japan Earthquake and pregnant women's awareness of social capital 3 to 9 months after the tsunami disaster. We analyzed data on responses to a questionnaire by 7451 pregnant women in their second to third trimesters. The proportions of social capital-related items were calculated in the north and south coastal areas of Miyagi Prefecture and were compared with national samples. The factors associated with social capital were estimated by use of multivariate logistic regression analyses. The proportion of women feeling that they had helpful neighbors was higher (69.0% vs 56.7%, P=0.0005), the proportion of women regarding their communities as safe and secure was lower (51.7% vs 62.4%, P=0.002), and the proportion of women feeling that most people were trustworthy was lower (23.7% vs 32.9%, P=0.006) in the north coastal area than nationwide. Such differences were not observed in the less severely affected south coastal area. Age of 35 years or older, extended family, college or university graduation, and being multiparous were associated with the feeling of having helpful neighbors. The current status of pregnant women's awareness of social capital in disaster-affected areas was revealed. Continuous monitoring and support may be necessary to address this issue.(Disaster Med Public Health Preparedness. 2017;11:355-364).

The Story of Cultural Assets and their Rescue: A First-Hand Report from Tohoku

Abstract:This essay explores what happens to objects, and the stories they tell, after a disaster. The focus is a project called the “Cultural Assets Rescue Operation” that was undertaken in the Ishinomaki area of Miyagi Prefecture by a coalition of experts, students, and volunteers to rescue objects after the devastating earthquake and tsunami of March, 2011. The objectives of the essay are 1) to provide a first-hand account of rescue activities; 2) to show how the idea of cultural assets emerges from a longer history of preservation, rescue and museums; and 3) to explore the way cultural assets are part of a complex narrative that is always bound to people, and always changing.

Design of the health examination survey on early childhood physical growth in the Great East Japan Earthquake affected areas.

BackgroundTo investigate the impact of the Great East Japan Earthquake on preschool children's physical growth in the disaster-affected areas, the three medical universities in Iwate, Miyagi, and Fukushima Prefectures conducted a health examination survey on early childhood physical growth.MethodsThe survey was conducted over a 3-year period to acquire data on children who were born in different years. Our targets were as follows: 1) children who were born between March 1, 2007 and August 31, 2007 and experienced the disaster at 43–48 months of age, 2) children who were born between March 1, 2009 and August 31, 2009 and experienced the disaster at 19–24 months of age, and 3) children who were born between June 1, 2010 and April 30, 2011 and were under 10 months of age or not born yet when the disaster occurred. We collected their health examination data from local governments in Iwate, Miyagi, and Fukushima Prefectures. We also collected data from Aomori, Akita, and Yamagata Prefectures to use as a control group. The survey items included birth information, anthropometric measurements, and methods of nutrition during infancy.ResultsEighty municipalities from Iwate, Miyagi, and Fukushima Prefectures and 21 from the control prefectures participated in the survey. As a result, we established three retrospective cohorts consisting of 13,886, 15,474, and 32,202 preschool children.ConclusionsThe large datasets acquired for the present survey will provide valuable epidemiological evidence that should shed light on preschool children's physical growth in relation to the disaster.

Characteristics of Physician Outflow from Disaster Areas following the Great East Japan Earthquake

ObjectiveThe shortage of physicians after a major disaster is a crucial issue. We aimed to evaluate the characteristics of physicians who left affected areas following the accident at Fukushima Daiichi Nuclear Power Plant caused by the Great East Japan Earthquake on March 11, 2011.MethodsUsing data from a physician census conducted in 2010 (pre-disaster) and 2012 (post-disaster), we evaluated changes in the number of physicians in affected areas. We then calculated the odds ratios and 95% confidence intervals using a logistic regression model to evaluate the association between physician characteristics and outflow. We also conducted stratified analyses based on physician characteristics.ResultsThe number of physicians decreased in Fukushima Prefecture (–5.3%) and increased in Miyagi Prefecture (2.8%). The decrease in Fukushima and increase in Miyagi were evident even after taking the prefecture’s population change into account (change in physician to population ratios: –1.9% and 3.2%, respectively). Compared with physicians who lived in areas >100 km from the nuclear power plant, physicians living 20–50 km and 50–100 km were, respectively, 3.9 times (95% confidence interval, 2.6–5.7) and 2.6 times (95% confidence interval, 1.7–3.8) more likely to migrate to distant areas. In the stratified analysis, younger physicians and those earlier in their careers had higher odds ratios for outflow than other physicians (P for interaction = 0.02 and <0.01, respectively).ConclusionsThe risk of outflow was greater among younger and early-career physicians in areas around the power plant. Political support may be necessary to recruit and retain such physicians, who will be responsible for future community health in the disaster area.

Comparison of isotope analysis and tank model calculation method to determine the snowmelt water ratio in river water

Isotope analysis of river water can be used to evaluate the contribution of snowmelt water in rivers because snow (precipitation) has relatively higher δ18O-NO3. Quantitative determination of snowmelt water input is needed for catchment environmental planning, agricultural planning and water resources planning in heavy snow regions, such as Miyagi Prefecture in Tohoku, Japan. We compared the measured δ18O-NO3 values in the Okura River (Sendai, Miyagi Prefecture) in the snowmelt seasons of 2013 and 2014 with the snowmelt water ratio calculated by the tank model for the years 1985 to 1989 and reported in Kato and Kurashima (1998). Although the seasonal periods of δ18O-NO3 measurements were not identical with the earlier period, with consideration of the meteorological conditions, variation in δ18O-NO3 was well explained by the contribution of snowmelt water to the river determined by the tank model. Thus, measured δ18O-NO3 could be used for catchment environmental planning in the region. This case study demonstrates the potential use of δ18O-NO3 values for determining the snowmelt water ratio in other rivers.

Comparison of isotope analysis and tank model calculation method to determine the snowmelt water ratio in river water

Isotope analysis of river water can be used to evaluate the contribution of snowmelt water in rivers because snow (precipitation) has relatively higher δ18O-NO3. Quantitative determination of snowmelt water input is needed for catchment environmental planning, agricultural planning and water resources planning in heavy snow regions, such as Miyagi Prefecture in Tohoku, Japan. We compared the measured δ18O-NO3 values in the Okura River (Sendai, Miyagi Prefecture) in the snowmelt seasons of 2013 and 2014 with the snowmelt water ratio calculated by the tank model for the years 1985 to 1989 and reported in Kato and Kurashima (1998). Although the seasonal periods of δ18O-NO3 measurements were not identical with the earlier period, with consideration of the meteorological conditions, variation in δ18O-NO3 was well explained by the contribution of snowmelt water to the river determined by the tank model. Thus, measured δ18O-NO3 could be used for catchment environmental planning in the region. This case study demonstrates the potential use of δ18O-NO3 values for determining the snowmelt water ratio in other rivers.

Age and growth of spear squid (Heterololigo bleekeri) caught in the coastal water off Miyagi Prefecture

Age and growth of spear squid (<i>Heterololigo bleekeri</i>) caught in the coastal water off Miyagi Prefecture

First record of the Golden Eagle Aquila chrysaetos at Lake Izunuma-Uchinuma, Miyagi Prefecture, Japan, and succeeding long distance migration

First record of the Golden Eagle <i>Aquila chrysaetos</i> at Lake Izunuma-Uchinuma, Miyagi Prefecture, Japan, and succeeding long distance migration