著者

Kazuyoshi Nishijima Takashi Maruyama Mathias Graf

出版者

Japan Society of Hydrology and Water Resources (JSHWR) / Japanese Association of Groundwater Hydrology (JAGH) / Japanese Association of Hydrological Sciences (JAHS) / Japanese Society of Physical Hydrology (JSPH)

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.6, pp.23-28, 2012 (Released:2012-03-13)

参考文献数

11

被引用文献数

17 27

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This paper performs a quantitative impact assessment of the climate change on typhoon wind risk, focusing on residential buildings in Japan. The risk is assessed based on (1) the typhoon event set extracted from the simulation by the super-high resolution atmospheric general circulation model developed within the KAKUSHIN program; (2) the probabilistic typhoon modeling scheme developed by our group; (3) a fragility model empirically estimated on the basis of the damage report of typhoon Songda in 2004 and the reproduced wind field by a mesoscale meteorological model; JMA-NHM. The main results are that in the future (2075–2099) at most locations of Japan: (1) extreme wind events (10-minute sustained wind speed exceeding 30 m/s) are more likely to occur; (2) the median of the annual maximum wind speed decreases; (3) the expected number of damaged residential buildings decreases, assuming that the profile of the building portfolio remains unchanged. Based on these results, the assumptions and inputs to the assessment are critically reviewed. Thereby, the needs of further research efforts toward more credible and comprehensive assessment are addressed.

著者

Kenji Tsuruta Hiroyuki Yamamoto Masanori Katsuyama Yoshiko Kosugi Motonori Okumura Naoko Matsuo

出版者

水文・水資源学会/日本地下水学会/日本水文科学会/陸水物理研究会

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.13, no.1, pp.1-6, 2019 (Released:2019-02-02)

参考文献数

32

被引用文献数

14

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Cryogenic vacuum distillation (CVD) methods have been widely used to extract water from unsaturated soil materials. However, recent studies have reported that extraction conditions (e.g. extraction time) and soil type can influence the stable isotope ratios of soil water extracted by CVD. We examined (i) the effects of extraction time on the stable isotope ratios of soil water extracted by CVD, and (ii) how the stable isotope ratios differed from those of soil water extracted by other methods. We first examined extraction times of 1–6 h, and observed no significant differences in the δ2H or δ18O values of extracted soil water for extraction times >2 h. However, extraction for 1 h collected only 48% of soil water, and the δ2H and δ18O values were significantly lower than those for extraction times >2 h. We then compared the stable isotope ratios of soil water extracted by CVD and centrifugation. Although the stable isotope ratios for both extraction methods were within the range of that of rainwater, the stable isotope ratios for water extracted by CVD were lower than those for water extracted by centrifugation. Our results highlight questions surrounding the use of CVD for stable isotope analysis of soil water.

著者

Takashi Maruyama Eriko Tomokiyo Junji Maeda

出版者

水文・水資源学会/日本地下水学会/日本水文科学会/陸水物理研究会

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.4, pp.40-44, 2010 (Released:2010-04-09)

参考文献数

4

被引用文献数

1 4

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The strong wind field caused by Typhoon Songda, which passed through Kyushu in Japan in 2004, was simulated numerically. A non-hydrostatic mesoscale model was used for the numerical simulation. The simulated wind field was compared with the observed wind field in terms of wind speeds and directions, which were measured by the wind observation network, NeWMeK. It was found that the temporal variation of the calculated wind speeds at 1 km hori-zontal mesh grids correspond to the average of the observed wind speeds over a ten to fifteen minute time period. The temporal variation of the calculated wind directions showed good agreement with the observations. The maximum values of the calculated wind speeds were highly correlated to the maximum values of the observed wind speeds. The applicability of the mesoscale model for the wind hazard assessment of buildings was examined, and it was found that the maximum values of the calculated wind speeds at higher altitudes showed higher correlations with the rates of damaged houses caused by Typhoon Songda.

著者

Yukiko Hirabayashi Yong Zang Satoshi Watanabe Sujan Koirala Shinjiro Kanae

出版者

水文・水資源学会/日本地下水学会/日本水文科学会/陸水物理研究会

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.7, no.1, pp.6-11, 2013 (Released:2013-03-09)

参考文献数

23

被引用文献数

10 38

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We report a time series (1948–2100) of global-scale meltwater from mountain glaciers and ice caps (MGI) estimated by the global glacier model HYOGA2. HYOGA2 calculates the temporal fluctuation of the mass balance for 24,234 individual glaciers worldwide. It covers 90% of the total glacier area, except for glaciers in Greenland and Antarctica. HYOGA2 also accounts for regionally distributed changes in glacier area and altitude associated with glacier retreat and advance. By computation of individual glacier changes, future dissipation and glacier mass and area changes can be simulated in the model. The cumulative volume loss of water between 1948 and 2005 was estimated to be 25.9 ± 1.4 mm sea level equivalent (SLE). A future projection under a high-emission scenario demonstrated significant losses of water from MGI equivalent to 60.3 ± 7.9 mm SLE between 1948 and 2060 and 99.0 ± 14.9 mm SLE between 1948 and 2099.

著者

Keisuke Ono So Kazama Seiki Kawagoe Yoshiyuki Yokoo Luminda Gunawardhana

出版者

Japan Society of Hydrology and Water Resources (JSHWR) / Japanese Association of Groundwater Hydrology (JAGH) / Japanese Association of Hydrological Sciences (JAHS) / Japanese Society of Physical Hydrology (JSPH)

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.5, pp.69-72, 2011 (Released:2011-11-02)

参考文献数

11

被引用文献数

3 7

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A gigantic earthquake with a magnitude of 9.0, the maximum ever recorded in Japan, struck the Tohoku region of Japan on 11 March, 2011. As a result, as many as 745 reservoirs in Fukushima prefecture were damaged. The failure of the earth-fill dam at the Fujinuma reservoir in Fukushima prefecture resulted in eight deaths in a village downstream. This was only the second such dam to fail completely in the recorded history of Japan, the first being Mannou Lake dam. The failure was caused by the Ansei Nankai earthquake in 1854. According to official records, of the 210,000 reservoirs in Japan, at least 20,000 dams are vulnerable to future earthquakes. Therefore, it is imperative that the failure mechanism of the Fujinuma reservoir be understood. As such, we developed several theories to explain what happened. Adherence to recommendations made in this report will reduce the potential for damage in future catastrophic events.

著者

Ty Tran Van Babel Mukand Singh Sunada Kengo Oishi Satoru Kawasaki Akiyuki

出版者

THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.3, pp.27-31, 2009

被引用文献数

1 6

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The objective of the study is to develop a GIS-based water infrastructure inventory (WII) for water resources assessment in the upper Srepok basin, Vietnam. The water availability and demand were estimated using common methods. Different water scarcity indicators were estimated to examine the water situation at district level under present and future conditions and future water development needs are assessed. Results reveal that the aggregated information on the basin scale misleads the issue of water situation, especially the scarcity at local level due to high spatio-temporal variations of water resources availability and demands. Most districts in the study basin will experience severe water scarcity in 2010 and 2020 in both physical and economic terms. Generated data from the WII shows very low percentage of water withdrawals in several districts with respect to available resources. Therefore, to meet future demand, significant investment in water infrastructure is needed.