Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union (AGU)  

Abstract

Improving tropical cyclone (TC) rainfall prediction is vital as climate change has led to an increase in TC rainfall rates. Enhanced reliability in predicting TC tracks has paved the way for statistical methodologies to make use of them in estimating current TC rainfall, achieved by identifying similar past TC tracks and obtaining their corresponding rainfall data. While the Fuzzy C Means (FCM) clustering algorithm is widely used, it has limitations stemming from its clustering‐centric design, hindering its ability to pinpoint the most appropriate similar TCs. Our study introduces the Sinkhorn distance, a novel similarity metric that measures the cost of transforming one set of data to another, for assessing TC similarity in rainfall prediction. Our findings indicate that utilizing Sinkhorn distance enhances the accuracy of TC rainfall predictions across the Western North Pacific region. When compared to the conventional approach using FCM, our Sinkhorn distance‐based methodology yields slightly better yet statistically significant results. The improvement is due to better identification of similar TCs, characterized by closer proximity of similar TC tracks to the target TC track, facilitated by Sinkhorn distance. This underscores how minor differences in TC track can alter rainfall distribution, emphasizing the critical importance of accurate track prediction in rainfall prediction and the need to reconsider how we categorize TCs together, which can have implications for climate and atmospheric sciences. Collectively, the inclusion of Sinkhorn distance stands as a valuable addition to our toolkit for discerning similar TC tracks, thus elevating the accuracy of TC rainfall predictions.

DOI： 10.1029/2023jd040246

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-16148

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.23-16131

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Abstract

The increasing rate of tropical cyclone (TC) rainfall has put populations in the Western North Pacific Region at greater risk of TC rainfall‐induced disasters. Statistical methodologies have shown potential in complementing existing prediction approaches. With TC track prediction accuracy significantly improving, statistical predictions have turned to TC tracks as a measure of similarity between TCs. Several studies have utilized Fuzzy C Means (FCM) to this end. However, FCM alone does not provide guidance on how many similar TCs should be used for predicting rainfall through ensemble averaging. While various number of ensemble members have been used to check the average error, such an approach yields only one number, which may not always be the most appropriate. In this study, we proposed a spatial and attribute filter to complement FCM identification of similar TCs. This filter excludes similar TCs with central pressure differences greater than 5% at strategic TC locations near land. The use of the filter yielded better rainfall prediction values than using FCM alone, as demonstrated in this study and validated against previous research findings. Our proposed model offers a reliable means of predicting TC rainfall when used in conjunction with accurately predicted TC tracks, representing a valuable complementary approach to existing prediction methods.

DOI： 10.1002/asl.1197

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Meteorological Society  

Abstract

The Asian Precipitation Experiment (AsiaPEX) was initiated in 2019 to understand terrestrial precipitation over diverse hydroclimatological conditions for improved predictions, disaster reduction, and sustainable development across Asia under the framework of the Global Hydroclimatology Panel (GHP)/Global Energy and Water Exchanges (GEWEX). AsiaPEX is the successor to GEWEX Asian Monsoon Experiment (GAME; 1995–2005) and Monsoon Asian Hydro-Atmosphere Scientific Research and Prediction Initiative (MAHASRI; 2006–16). While retaining the key objectives of the aforementioned projects, the scientific targets of AsiaPEX focus on land–atmosphere coupling and improvements to the predictability of the Asian hydroclimatological system. AsiaPEX was designed for both fine-scale hydroclimatological processes occurring at the land surface and the integrated Asian hydroclimatological system characterized by multiscale interactions. We adopt six approaches including observation, process studies, scale interactions, high-resolution hydrological modeling, field campaigns, and climate projection, which bridge gaps in research activities conducted in different regions. Collaboration with mesoscale and global modeling researchers is one of the core methods in AsiaPEX. We review these strategies based on the literature and our initial outcomes. These include the estimation and validation of high-resolution satellite precipitation, investigations of extreme rainfall mechanisms, field campaigns over the Maritime Continent and Tibetan Plateau, areas of significant impact on the entire AsiaPEX region, process studies on diurnal- to interdecadal-scale interactions, and evaluation of the predictabilities of climate models for long-term variabilities. We will conduct integrated observational and modeling initiative, the Asian Monsoon Year (AMY)-II around 2025–28, whose strategies are the subregional observation platforms and integrated global analysis.

DOI： 10.1175/bams-d-20-0220.1

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Other Link： https://journals.ametsoc.org/downloadpdf/journals/bams/104/4/BAMS-D-20-0220.1.xml

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Pre-release is the discharge from a reservoir before a flood to enhance flood control capability. Its success depends on the performance of rainfall forecasting. However, there is little information regarding the causal relationship between its performance and the success of pre-release. Therefore, the rainfall forecast required for pre-release at 326 multi-purpose reservoirs in Japan is shown quantitatively in this paper. In our analysis, pre-release was simulated based on tentative rainfall forecasts made using observed rainfall data from a period of 17 years (2006 to 2022) with some processing. Then, outputs were evaluated in terms of two risks: not avoiding emergency spillway gate operation and no recovery of water use capacity. The results of five elements were reached: (1) the characteristics of situations requiring pre-release, the required (2) forecast length and (3) spatial resolution, the required accuracy of (4) the rainfall amount, and (5) the position of rainfall zone. For (1), pre-release is required nationwide in typhoons or stationary fronts at a frequency of four instances per year. For (2) and (3), assuming perfect accuracy, the current specifications of rainfall forecast in Japan: forecast length of 84 h or more and the combined use of 5 km and 20 km spatial resolution are generally effective in themselves. For (4) and (5), possible uncertainties in the rainfall amount and the position of rainfall zone needs to be decreased by one digit for avoiding emergency spillway gate operations, while excessive pre-release tends not to result in no recovery of water use capacity.

DOI： 10.3390/w15071277

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Copernicus GmbH  

Abstract. Quantifying continental-scale river discharge is essential for understanding the terrestrial water cycle, but it is susceptible to errors caused by a lack of observations and the limitations of hydrodynamic modeling. Data assimilation (DA) methods are increasingly used to estimate river discharge in combination with emerging river-related remote sensing products (e.g., water surface elevation (WSE), water surface slope, river width, and flood extent). However, directly comparing simulated WSE to satellite altimetry data remains challenging (e.g., because of large biases between simulations and observations or uncertainties in parameters), and large errors can be introduced when satellite observations are assimilated into hydrodynamic models. In this study we performed direct, anomaly, and normalized value assimilation experiments to investigate the capacity of DA to improve river discharge within the current limitations of hydrodynamic modeling. We performed hydrological DA using a physically based empirical localization method applied to the Amazon basin. We used satellite altimetry data from ENVISAT, Jason 1, and Jason 2. Direct DA was the baseline assimilation method and was subject to errors due to biases in the simulated WSE. To overcome these errors, we used anomaly DA as an alternative to direct DA. We found that the modeled and observed WSE distributions differed considerably (e.g., differences in amplitude, seasonal flow variation, and a skewed distribution due to limitations of the hydrodynamic models). Therefore, normalized value DA was performed to improve discharge estimation. River discharge estimates were improved at 24 %, 38 %, and 62 % of stream gauges in the direct, anomaly, and normalized value assimilations relative to simulations without DA. Normalized value assimilation performed best for estimating river discharge given the current limitations of hydrodynamic models. Most gauges within the river reaches covered by satellite observations accurately estimated river discharge, with the Nash–Sutcliffe efficiency (NSE) > 0.6. The amplitudes of WSE variation were improved in the normalized DA experiment. Furthermore, in the Amazon basin, normalized assimilation (median NSE =0.50) improved river discharge estimation compared to open-loop simulation with the global hydrodynamic model (median NSE =0.42). River discharge estimation using direct DA methods was improved by 7 % with calibration of river bathymetry based on NSE. The direct DA approach outperformed the other DA approaches when runoff was considerably biased, but anomaly DA performed best when the river bathymetry was erroneous. The uncertainties in hydrodynamic modeling (e.g., river bottom elevation, river width, simplified floodplain dynamics, and the rectangular cross-section assumption) should be improved to fully realize the advantages of river discharge DA through the assimilation of satellite altimetry. This study contributes to the development of a global river discharge reanalysis product that is consistent spatially and temporally.

DOI： 10.5194/hess-27-647-2023

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.78.2_i_103

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.78.2_i_529

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.78.2_i_511

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.78.2_i_1237

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jclepro.2022.133812

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Language：English   Publishing type：Research paper (scientific journal)  

We developed a 0.01-degree gridded precipitation dataset of Japan based on historical observation datasets covering 1926 to 2020. Historical observations conducted by the Japan Meteorological Agency and other Japanese bureaucratic agencies were spatially interpolated using the inverse distance weighting method at daily and hourly temporal resolutions. Optimal parameterization for our interpolation process was selected by comparing interpolated results of various parameter combinations with precipitation observation conducted by the University of Tokyo Forests. We conducted cross-validation for over 1,000 stations with sufficient data throughout our data period and verified our product can reproduce the temporal variability of local precipitation. The strong points of our precipitation dataset are its high spatiotemporal resolution and the abundance of point precipitation source data. We expect our dataset to be highly relevant to various future studies as it can serve multiple purposes such as forcing data for hydrological models or a database for analyzing the characteristics of historical rainfall events.

DOI： 10.1038/s41597-022-01548-3

PubMed

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Publishing type：Research paper (scientific journal)   Publisher：Copernicus GmbH  

Abstract. Global hydrological models that include human activities are powerful tools for assessing water availability and use at global and continental scales. Such models are typically applied at a spatial resolution of 30 arcmin (approximately 50 km). In recent years, some5 arcmin (9 km) applications have been reported but with numerous technical challenges, including the validation of calculations for more than 1 × 106 grid cells and the conversion of simulation results into meaningful information relevant to water resource management. Here, the H08 global water resources model was applied in two ways to Kyushu island in Japan at a resolution of 1 arcmin (2 km), and the detailed results were compared. One method involved feeding interpolated global meteorological and geographic data into the default global model (GLB; in accordance withprevious high-resolution applications). For the other method, locally derived boundary conditions were input to the localized model (LOC; this method can be easily extended and applied to other regions, at least across Japan). The results showed that the GLB cannot easily reproduce the historical record, especially for variables related to human activities (e.g., damoperation and water withdrawal). LOC is capable of estimating natural and human water balance components at daily timescales and providing reliable information for regional water resource assessment. The results highlight the importance of improving data preparation and modeling methods to represent water management and use in hyper-resolution global hydrologysimulations.

DOI： 10.5194/hess-26-1953-2022

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1353/tech.2022.0053

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Language：Japanese  

DOI： 10.2208/jscejhe.77.2_I_109

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.77.2_i_217

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.77.2_i_1207

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.77.2_i_85

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejer.78.5_i_163

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Language：Japanese   Publisher：SOCIETY OF ENVIRONMENTAL SCIENCE, JAPAN  

People in society need to better understand the risks of climate change in order to achieve a decarbonized society for the Paris target and to adapt to the changing climate. For this reason, our research group has developed a method for visualizing the interconnections among climate risks comprehensively and in an easy-to-understand manner. In this study, the visualizations of interconnections among climate risks related to the seven sectors (water resources, food, energy, industry and infrastructure, natural ecosystems, disasters and security, and health) are explained, and the overall picture of the climate risk chains are presented. In addition, we will discuss the usefulness of the visualizations of climate risk interconnections (network maps and flowcharts) and the importance of dialogues with citizens on climate risk, by introducing an example of dialogue events conducted by using the visualization results.

DOI： 10.11353/sesj.34.214

CiNii Research

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/jjshwr.34.161

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Publishing type：Research paper (scientific journal)  

DOI： 10.3390/rs13101959

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Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing  

DOI： 10.1088/1748-9326/abce80

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Other Link： https://iopscience.iop.org/article/10.1088/1748-9326/abce80/pdf

Publishing type：Research paper (scientific journal)   Publisher：Institute of Electrical and Electronics Engineers (IEEE)  

DOI： 10.1109/tgrs.2020.2996239

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Blackwell Publishing Ltd  

DOI： 10.1029/2020WR027876

Scopus

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.2139/ssrn.3970225

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Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing  

DOI： 10.1088/1748-9326/abc586

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Other Link： https://iopscience.iop.org/article/10.1088/1748-9326/abc586/pdf

Publishing type：Research paper (scientific journal)  

DOI： 10.3390/w12113210

Scopus

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.76.2_i_109

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.76.2_i_535

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.76.2_i_115

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.76.2_i_823

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41598-020-75440-8

Web of Science

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/jjshwr.33.111

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.75.1_299

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

<p> A large ensemble of climate simulations is a powerful tool for estimating rainfall extremes under future climate. It has been also suggested that, to first order, the intensification of heavy rainfall in a warmer climate could follow the Clausius-Clapeyron (CC) relationship (7%/°C). Yet, observed evidence that detects CC-related changes both in daily and sub-daily (e.g., hourly) rainfall extremes between two periods (namely the past and the present) and model analyses with observations are limited. We show that the intensification rate of subdaily extremes is higher than that of daily extremes. This result supports a recently published analysis for Australia. We also show that the intensification rate of rainfall extremes derived from climate models with a multiple ensemble coincides with that derived from observations. On the other hand, we show that in some cases, the intensification rate of rainfall extremes derived from climate models from the past period to the future period is less than that from the CC relationship theory. This is a brief paper to provide the latest knowledge about the intensification of rainfall extremes and further analyses are required.</p>

DOI： 10.2208/jscejhe.75.2_i_1129

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.75.2_i_919

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.75.2_i_1111

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.75.2_i_1

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.75.2_i_1195

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Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Coping with climate change in socio-ecological systems is one of the most urgent issues facing the world. This is particularly true in socio-ecological systems, where climate not only influences social and ecosystem dynamics, but also modulates their interaction. In this paper, we presented a conceptual framework through a literature review and a trend analysis for assessing the impact of climate change that incorporates socio-ecological interactions. In particular, we focused on the Mongolian pastoral system, which has tightly coupled socio-ecological interactions, as a model for describing the framework. Our framework suggests that the flexibility in mobility of herders is the principal factor in determining the vulnerability of the socio-ecological system to climate change. The flexibility varies along a climatic gradient and socio-ecological interactions in each region have evolved to be suited to its local climate regime. Herders in northern and central regions of Mongolia move shorter distances, and less flexible, than those in southern (Gobi) region. Climatic hazards, on the other hand have been increasing across Mongolia with a trend toward warmer and drier conditions since the 1960s. We suggest that further warming and drying would have the greatest impact on northern and central regions due to lower flexibility in mobility among herders there coupled with the much higher livestock density in the regions. The findings support that maintaining flexibility of mobile herding will likely be crucial to reducing the vulnerability of the Mongolian pastoral system to climate change.

DOI： 10.3390/su11215883

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s00382-019-04868-0

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

DOI： 10.3390/w11040829

Scopus

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s10669-018-9684-7

Scopus

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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DOI： 10.1029/2018WR023434

Web of Science

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.75.2_i_1105

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2018EF000945

Web of Science

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

<p>Water scarcity indicators have been used for global water resources assessments, as there is no adequate physical quantity to indicate water scarcity. The most widely used indicators are the Withdrawal to Availability (WTA) and the Availability per capita (APC). WTA is the ratio of annual water withdrawal to annual water resources, and empirically, a region is judged under water scarcity when it exceeds 0.2 and 0.4. APC is the annual volume of water resources per person, and a region is judged so when it falls below 1700 m3/year/person and 1000 m3/year/person. Both are widely accepted, but the concrete basis for these thresholds has never been presented. Here, we conducted a series of global simulations using the latest global water resource model H08, and investigated what kind of water resources state the WTA and APC thresholds represent. This contribution is a summary of recent publication in Water Resources Research in 2018.</p>

DOI： 10.11520/jshwr.32.0_14

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Blackwell Publishing Ltd  

DOI： 10.1029/2018JD028864

Scopus

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Publishing type：Research paper (scientific journal)  

DOI： 10.3390/w10111614

Scopus

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/w10111614

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2018WR022931

Web of Science

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Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2018WR022931

Scopus

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DOI： 10.1002/2017EF000671

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/w10070872

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1748-9326/aaac08

Web of Science

Scopus

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11625-018-0530-0

Web of Science

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Other Link： http://link.springer.com/content/pdf/10.1007/s11625-018-0530-0.pdf

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11625-018-0536-7

Web of Science

Scopus

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.5194/hess-22-789-2018

Web of Science

Scopus

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Language：Japanese   Publisher：一般社団法人 日本土壌肥料学会  

DOI： 10.20710/dohikouen.64.0_155_1

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.74.5_i_1219

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.74.i_211

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.74.5_i_1213

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.74.i_145

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/w9100763

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/2017MS000943

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/2017GL072874

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley-Blackwell  

DOI： 10.1002/2016JD025222

Scopus

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/02626667.2016.1241398

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/2016JD025222

Web of Science

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejer.73.i_407

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.73.i_175

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

&nbsp;Natural disasters caused by heavy rainfall occur every year in Japan. In this study, a new method for generating synthetic extreme heavy rainfall events using Monte Carlo Simulation has been developed. We used AMeDAS analyzed rainfall data which is high resolution grid rainfall data. Depth area duration (DAD) analysis has been conducted to extract extreme rainfall events in the past. In the Monte Carlo Simulation, extreme rainfall event is generated based on events extracted by DAD analysis. We compared 100-year probable rainfall calculated by this method with other traditional method. New developed method method enables us to generate synthetic extreme rainfall events considering time and spatial scale.

DOI： 10.2208/jscejhe.73.I_373

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.73.i_121

J-GLOBAL

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Publisher：Copernicus {GmbH}  

DOI： 10.5194/tc-2016-222

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.5194/hess-20-4143-2016

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/2016JD024939

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/srep29723

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3389/feart.2016.00042

Web of Science

Scopus

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Publisher：Copernicus {GmbH}  

DOI： 10.5194/hess-2016-119

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

The H08 global water resources model enables us to simulate global water availability and use at high spatial and temporal resolution. H08 has been used to assess the impact of climate change and estimation of water footprint, and others. To express human water use more realistically, water abstraction schemes were substantially enhanced, and global water availability and use in circa 2000 were reconstructed.

DOI： 10.11520/jshwr.29.0_5

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

&nbsp;Heavy precipitation event occurred for 8 to 10 September, 2015, over Tochigi and Ibaraki Prefectures caused an over-topping and an outburst of the left levee of Kinu-river in Wakamiyato and Misaka-cho districts in Joso city, Ibaraki prefecture around 6am and 1pm on 10 September, respectively. This precipitation event was caused by clustered linear rain bands influenced by Typhoon Etau (No 18) and Kilo (No 17). This paper aims to report our field investigations held on 10, 15, and 19 September, and to raise a couple of discussions for further improvement of flood control and river basin management in Japan.

DOI： 10.2208/jscejhe.72.I_1273

CiNii Books

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

&nbsp;This study employs the updated climate scenarios and socio-economic scenarios in order to evaluate uncertainties and characteristics of projected economic impacts using impact functions of FUND model, which is as integrated assessment model having detailed sector-specific impact functions. We, in particular, focused on impact functions for water sectors: water resources, tropical storm, and sea level rise. The result susggested damages in three sectors would keep increasing under Representative Concentratin Pathwas 8.5 scenario, regardless of socio-economic scenarios. In addition, comparions of damages among three socio-economics scenarios (i.e. Shared Socio-econoic Pathways (SSPs) 1-3) revealed damages in water sector and tropical storm follow SSP3 > SSP1 &asymp; SSP2, while damages in sea level rise follows SSP3 > SSP1 > SSP2.

DOI： 10.2208/jscejer.72.I_213

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Previous studies have employed deterministic equations to project global economic losses by tropical cyclones. However, the relations between Tropical Cyclone (TC) risk and its explanatory variables (i.e. hazard, exposure, and vulnerability) would be stochastic rather than deterministic, suggesting possible advantage of using probability based method for global TC risk projection. In this study, we developed regression models which are based on Bayesian modeling and estimated global TC economic losses with taking account of stochastic fluctuations of losses. Furthermore, we suggest hierarchical Bayesian models considering TC intensity and geographical characteristics. The hierarchical Bayesian models yielded to improved performance in estimating TC losses in historical period.

DOI： 10.11520/jshwr.29.0_2

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Future changes in the proportions of global precipitation by different weather systems (tropical cyclones, centers and fronts of extratropical cyclones, and others) are quantified based on objective weather system detection method and the climate model realizations (1980-1999 and 2080-2099) from the Coupled Model Intercomparison Project Phase 5 (CMIP5). It was found that the subtropics, particularly in the Pacific and North Atlantic, are the regions where the weather system-wise proportions of annual and extreme precipitation display notable changes, indicating distinct shifts in climate regimes. All of these regions have a common feature: they are substantially influenced by, and are in reach of, many weather systems in the present climate.

DOI： 10.11520/jshwr.29.0_12

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley-Blackwell  

DOI： 10.1002/2016JD024939

Scopus

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

With more and more regions in the world are facing water scarcity due to the climate change and human activities, various technologies to increase the water supply such as seawater desalination have been promptly developed by the projects with huge investment cost, thus it is crucially necessary to assess their costs and benefits to determine whether or not the projects are financially feasible. In this study, it chooses to develop an empirical methodology to assess the cost and benefit of seawater desalination within three socioeconomics scenarios, i.e. SSP1, SSP2 and SPP3 and furtherly estimate the optimal time to apply (OTA) of such technology basing on their different income levels of those scenarios countries.

DOI： 10.11520/jshwr.29.0_39

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Thailand Monsoon Domain weather is govern by the Asian Summer monsoon which displays high variability in seasonal and interannual time scales. Different precipitation providing weather systems demonstrate different response to different weather related phenomenon such as Pacific-Japan (PJ) oscillation. Precipitation is decomposed into several systems namely tropical cyclones, extra tropical cyclones and fronts, and westward propagating disturbances, the precipitation which not related with any other systems categorized as &ldquo;others&rdquo;. Several objective detection methodologies were utilized in detecting different precipitation providing weather systems. The decomposed precipitation amounts related to different weather systems were correlated with PJ pattern and the correlations found to be in a positive phase in around Thailand. Positive PJ pattern tend increase precipitation events but not tropical cyclones and precipitation in late summer tend to enhanced by positive PJ phase. Dynamical response of the PJ pattern need to be further studied in association with different precipitation providing weather systems.&nbsp;&nbsp;

DOI： 10.11520/jshwr.29.0_69

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

The large uncertainty in future glacier projections partly results from a substantial range in future climate conditions projected by global climate models. Few studies have investigated local differences in impact of glacier projection caused from climate model projection spread within High Mountain Asia (HMA). Also intercomparison of climate models to understand specific model characteristics as the climate forcing is required. This simulation illustrated glacier area projection spread among climate models in HMA at sub regional scale. The largest range of area projections among 8GCMs is found at Western Himalaya. CCCma-CanESM2 and MRI-CGCM3 projected the largest and the smallest glacier area loss individually at almost all sub regions. CCCma-CanESM2 shows the highest temperature increases while MRI-CGCM3 shows a neutral to weakly positive trend and those could be cause the area projection differences. This study is a primary step to reduce the uncertainty of glacier projection arising from future climate projection spread.

DOI： 10.11520/jshwr.29.0_62

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Water resources is vital in social and economic activities.&nbsp;Total global water use is increasing, mainly due to economic and population growth in developing countries. &nbsp;It has one of risk with high agreement and robust evidence that freshwater-related risks of climate change increase significantly with increasing greenhouse gas concentrations.&nbsp;It is difficult to compare the risk with other field risk for considering both adaptation and mitigation policy.&nbsp;Economic losses of water scarcity due to climate changed has been estimated by economic researchers. We have no certainty at all about integration between hydrology and economics despite their efforts through several decades. In this study, we highlight key concerns about economic loss estimations of water resources due to climate change using several previous papers.

DOI： 10.11520/jshwr.29.0_121

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Drought is phenomena of below-normal precipitation and affecting people and nature environment. It was suggested from previous studies that plant species diversity enhances community vulnerability for drought. Extreme climatic event affect community assembly and evolution. Legacies of land use activities continue to influence ecosystem structure and function for decades or centuries or even longer after those activities ceased. These factors, however, did not consider with evaluation of drought effect in global scale studies.We evaluated the effect of annual precipitation in drought, pre-drought and post-drought year, plant species richness, land-use hiatory and soil type on EVI in drought, pre-drought and post-dtought year.

DOI： 10.11520/jshwr.29.0_68

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejer.72.i_241

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejer.72.i_35

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

&nbsp;Separation of permanent water body and temporal water body is essential for the grasp of global water distribution. Global 3-second Water Body Map (G3WBM) is a global scale high-resolution water body map recently-developed by the authors, which separates water body types by the idea of water frequency, using multi-temporal Landsat data. In this paper, we further improved the accuracy and computational efficiency of G3WBM algorithms, and refined the resolution from 90m to 30m. The validation against U.S. National Hydrography Dataset revealed that, although some small water bodies could not be visualized, more than 85% of permanent water bodies were classified correctly. Comparison between the water body mask constructed in this paper and G3WBM in the U.S. showed that water judgment accuracy was improved and over 2600km² of temporal water has been newly separated from permanent water.

DOI： 10.2208/jscejhe.72.I_421

CiNii Books

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DOI： 10.1088/1748-9326/10/12/124011

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1748-9326/10/12/124011

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DOI： 10.1175/MWR-D-14-00228.1

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2480/agrmet.D-14-00034

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/02626667.2014.888067

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Language：English  

DOI： 10.1002/2014WR015602

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.71.i_301

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Water scarcity due to climate changes and growing human population is a major concern for the world. Adaptation strategies should be developed for water scarcity in the future. Previous studies assessed the future water availability by hard technology as adaptation strategies. On the other hand, soft path such as water law would also be important for adaptation strategies. Water trade is reallocation of water among water users. If water trades are permitted in these areas, water can be moved from surplus areas/sections to critical need areas/sections. However the factors that determined the establishment of water transfer are not clear. Here we reviewed the several water trades in Australia, California and Chile to find factors that affecting water trades. Then we present potential areas to apply the water market based on the factors by investigating the water law in 197 countries and regions.

DOI： 10.11520/jshwr.28.0_100091

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

Water shortage has been becoming one of the most crucial issues in China, because of the rapidly increasing water demand for economic development. One way of alleviating water scarcity is to increase the efficiency of water use without developing additional water supplies. Therefore it is essential to develop a holistic policy tool which can help the policy-makers to decide the usage of water wisely. The fundamental work is to explicitly quantify the agricultural water use efficiency in target areas. In this study, the agriculture water use efficiency is measured by the Data Envelopment Analysis (DEA) method, and recommendations of sustainable water use are provided.

DOI： 10.2208/jscejhe.71.I_145

J-GLOBAL

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DOI： 10.3178/hrl.9.103

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Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.5194/piahs-371-69-2015

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：Japanese  

DOI： 10.2208/jscejhe.71.I_445

J-GLOBAL

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Copernicus GmbH  

DOI： 10.5194/piahs-371-69-2015

Scopus

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Drought is phenomena of below-normal precipitation and affecting people and nature environment. It was suggested from previous studies that plant species diversity enhances community vulnerability for drought. Extreme climatic event affect community assembly and evolution. Legacies of land use activities continue to influence ecosystem structure and function for decades or centuries or even longer after those activities ceased. These factors, however, did not consider with evaluation of drought effect in global scale studies.We evaluated the effect of plant species richness, land-use hiatory and soil type on NDVI in drought, pre-drought and post-dtought year.

DOI： 10.11520/jshwr.28.0_100123

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Rapid increasing water demand due to population growth with supply constraints under climate change might be raised up the risk of transboundary water conflicts. So far, it is not clarify that water scarcity really was affected on the occurrence of international water conflicts. In this study, we statistically explored the relationships of water conflict to several institutional factors as well as level of water scarcity in international river basins.

DOI： 10.11520/jshwr.28.0_100112

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/02626667.2013.862338

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley-Blackwell  

DOI： 10.1002/2014JD021734

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/2014JD021734

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DOI： 10.1088/1748-9326/9/6/064017

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DOI： 10.1088/1748-9326/9/6/064014

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DOI： 10.1007/s12665-013-2778-0

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/2014GL059744

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DOI： 10.1175/JCLI-D-13-00310.1

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1175/JHM-D-13-052.1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley-Blackwell  

DOI： 10.1002/2013JD020398

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/02626667.2013.857411

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/2013JD020398

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.5194/hess-18-4289-2014

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.5194/hess-18-621-2014

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

In Asia, the average river flow is projected to increase into the future. Despite the importance of glacier melts towards some major river basins in Asia, it is unclear the extent of contribution of glacier melts towards river flow in the context of climate change. Here we attempt to add the runoff outputs of CMIP5 models with glacier melts into a &ldquo;total runoff&rdquo;. The runoff outputs of six CMIP5 models are forced by RCP 8.5; and the glacier melts are estimated using a mass-balanced glacier model forced by CMIP5 models. We assess the impact of climate change on the water resources in 11 Asian glacierized basins. Our simulations show that annual runoff considering glacier melts would increase in all basins. However, decrease in the relative contribution of glacier melts to the total runoff until the end of 21^st century in some basins might have implications on their water supplies.

DOI： 10.11520/jshwr.27.0_100018

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Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.70.i_463

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Extreme drought event affects the processes of community assembly and evolution in arid land. In addition, legacies of land use activities, no less than climatic effects, also continue to influence ecosystem structure and function for decades or centuries or even longer after those activities have ceased. Thus, we hypothesized that if there is long history of anthropogenic land use at certain arid area, the ecosystem in such area can reduce vulnerability to typical land use and extreme drought. However, the interaction between the history of land use and drought vulnerability is still not clearly established in literatures. In this study, we empirically investigated the interaction using HIDE3.1 data and satellite derived PDSI data in Sub-Saharan Africa the Eurasian Continent and U.S.A . There are high-frequency droughts in Sub-Sharan Africa. We found that resistance and resilience under longer history of land use such as in Sub-Saharan Africa are higher than these at the region of shorter history such as in U.S.A.

DOI： 10.11520/jshwr.27.0_100125

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Water is indispensable resources for the society. Transition toward sustainable use of water is needed because water demand is rapidly growing globally. We projected future production of desalination globally based on the global water resources assessment carried out by Hanasaki and others.

DOI： 10.11520/jshwr.27.0_100133

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

Trans-boundary river basins have been affected by flow variability caused by water use. Down-stream countries are often forced to face water shortage and sometimes dispute and compete with up-stream countries for shared water resources. To avoid future water conflict, the basin at risk should be identified by hydrological variability and institutional mechanisms which agreements contains. This paper investigates the potential risk for trans-boundary water conflict in the future. This risk can be estimated with two components. One is water stress level projected by a global water resource model and the other is vulnerability level defined by both trans-boundary freshwater agreement and river basin organization. As a result, the potential risk for trans-boundary water conflict in Africa and Central Asia is found.

DOI： 10.2208/jscejhe.70.I_475

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

Tropical cyclones (TCs) are often associated with heavy rains and storm surges that bring severe damage to human society. Previous studies have indicated the possible increasing of TC intensity in the future. Thus, it is important to predict future TC losses. In this study, we developed regression models to estimate economic losses caused by TCs at global scale. The models used pressure drop, exposed population and gross domestic product (GDP) per capita as inputs. Furthermore, economic losses in 2100 were projected by considering socioeconomic and/or climate change based on A1B scenario. In addition, future losses with socioeconomic and climate change under four different social scenarios were also estimated. In the results, global economic loss and ratio of economic loss to GDP would increase with socioeconomic and climate change. The increase of losses is mainly because of socioeconomic changes (particularly in the North Indian and the Southern Hemisphere regions) rather than climate change.

DOI： 10.2208/jscejhe.70.I_469

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

Tropical Cyclones (TCs) have caused severe disasters in various places in Japan. Kochi prefecture has experienced TC disasters various times, and thus, it is important to evaluate impact of future change of TCs on Kagami river basin. In this study, we developed an algorithm to evaluate the impacts of future change of precipitation caused by TCs into discharge. The algorithm classifies TCs into some patterns according to track and intensity of TCs. Then, stochastically simulated TCs are classified into the extracted TC patterns. Subsequently, the functions to generate TC induced precipitation are also estimated for each of TC patterns. Execution of the proposed algorithm to Kagami river basin indicated annual maximum discharge might increase by nearly 30% when we consider 21 % decreasing of central pressure and future change of thermodynamic environment.

DOI： 10.2208/jscejhe.70.I_385

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Other Link： https://jlc.jst.go.jp/DN/JLC/20010510511?from=CiNii

Language：English   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Evapotranspiration (ET) over a diverse land use area in northern Thailand was successfully estimated by long-term eddy covariance measurements. Some measurement gaps due to instrumentation problems and administrative difficulties were unavoidable. Monthly ET trends revealed a maximum of 150 ± 10 mm in June and a minimum of 60 ± 10 mm in January. The annual mean ET was estimated to be 1300 ± 140 mm. The interannual variation in ET reflects the response of the land surface to meteorological events and land use/cover changes (LUCC); however, the effect of rainfall variation on ET was greater than that of LUCC. Effective heterogeneity was evaluated using the Bowen ratio; such information will be useful for understanding the effect of land surface heterogeneity on latent and sensible heat fluxes.<br>

DOI： 10.3178/hrl.8.45

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.70.i_361

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Language：Japanese  

DOI： 10.2208/jscejhe.70.I_307

J-GLOBAL

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.2208/jscejhe.70.I_565

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Future water resources and food productivity was estimated using the global integrated water resource assessment model H08 and the global glacier model HYOGA2. The development of climate scenario which includes advanced bias correction method developed for this study enables us to conduct simulation using multiple General circulation models. The estimation took into account the effect of not only climate change but also socioeconomic change and glacier melting. The result indicated the decrease of food productivity due to the increment of water and heat stress for crop. We will present the difference of climate scenario, socioeconomic scenario, and with and without glacier melt water in the conference.

DOI： 10.11520/jshwr.27.0_100017

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.agrformet.2013.05.007

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/NCLIMATE1911

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Language：Japanese   Publisher：SOCIETY OF ENVIRONMENTAL SCIENCE, JAPAN  

Biofuel is expected to contribute reduction of greenhouse gas emission as a high renewable energy, while a growing demand for biofuels increases the risk of impairs food security. However, previous assessments of the potential of bioenergy are still very rare. Further, recent studies generally tend to overestimate the potential of bioenergy because they considered all current non-agricultural lands as potential cultivation for biofuel product. In this paper, we estimated the potential amount of energy crop globally. Two different land-cover types, abandoned land and fallow land, are considered to evaluate energy crop plantations. The estimated global bioenergy potential is 237EJ on abandoned land and fallow land. This value is equivalent to about 47% of current world primary energy demand. Although it is smaller than previous one due to considering different terms of potential land use, we believe that our estimation is relatively close to realistic situation. In addition, soil degradation on abandoned land causes decreased number of global bioenergy potential on abandoned land, from 128EJ to 94EJ.

DOI： 10.11353/sesj.26.287

CiNii Books

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Other Link： http://agriknowledge.affrc.go.jp/RN/2010852792

Language：English   Publishing type：Part of collection (book)   Publisher：Taylor and Francis  

DOI： 10.4324/9780203141564

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Language：English  

DOI： 10.1038/ngeo1688

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Models to estimate glacier mass balance are critically sensitive to uncertainty of precipitation input. Although, there are large spatial variations of precipitation on glacier mountain areas, reliable precipitation data is not well established in these areas because this remote region lacks a dense gauge network. In this study, a precipitation data set with fine special resolution from 1998 to 2007 at daily time scales at high mountain area in South Asia using satellite radar observation has developed. The mass of glaciers was calculated using a glacier model.

DOI： 10.11520/jshwr.26.0.22.0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Hydrology and Water Resources  

DOI： 10.3178/hrl.7.6

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.2208/jscejhe.69.I_379

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DOI： 10.2208/jscejhe.69.I_337

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DOI： 10.2208/jscejhe.69.I_391

J-GLOBAL

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DOI： 10.2208/jscejhe.69.I_385

J-GLOBAL

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

Global- and continental-scale snow simulation has been used to produce snow estimates and attribute the change of snow into hydrological variables. However, uncertainties in global- and continental-scale snow simulation due to model structure, model parameters, and meteorological forcing has not been well documented. In the present study, we used MATSIRO land surface model and conducted ensemble simulations for snow, i.e., perturbed parameter ensemble simulation and multi precipitation ensemble simulation. The results show that uncertainties in parameters are larger in the melting season than accumulation season and uncertainties in precipitation are large in accumulation seasons. The uncertainties of parameters in melting season are comparable to that of precipitation.

DOI： 10.2208/jscejhe.69.I_439

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

Freshwater creatures are affected by mankind's impact such as irrigation and water pollution more than by land and marine creature and this leads to ecosystem deterioration in the river. The purpose of this study is to evaluate the these change every global river using future estimated river discharge and decide dangerous area for the survive of fish species. The results showed that the area which will be dangerous in the future were North America, South America, Africa, Oceania, South Asia and East Asia. The present study suggests that deterioration of river ecosystem will happen in many areas of the world in the future.

DOI： 10.2208/jscejhe.69.I_1267

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Language：English   Publishing type：Research paper (international conference proceedings)  

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DOI： 10.1080/02626667.2013.814914

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DOI： 10.5194/hess-17-2393-2013

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DOI： 10.5194/hess-17-2375-2013

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

A Bias-correction method applied to daily climate variables simulated by multiple General Circulation Models (GCMs) is proposed in this study. The purpose of this study is to propose a method which preserves the trend of not only mean but also variation of statistics. To validate the proposed method, the bias-corrected data in the period 1981-2005 of 5 GCMs are compared among methods. The proposed method can generally reduce the difference between bias-corrected and observed data than previous method except for the daily lower value. Furthermore, the difference of method is smaller than that between with or without bias-correction. This study successfully proposed a new bias-correction method which has two advantages; the trend of variation is preserved; the reproducibility of observed data is better than previous method in monthly/daily higher value.

DOI： 10.11520/jshwr.26.0.200.0

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J-GLOBAL

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2012JD018192

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2012WR011869

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2011JD015890

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DOI： 10.1038/NGEO1476

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DOI： 10.1016/j.jhydrol.2012.02.045

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DOI： 10.1007/s00704-011-0520-y

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DOI： 10.1002/asl.367

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DOI： 10.1007/s00484-011-0445-2

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J-GLOBAL

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J-GLOBAL

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J-GLOBAL

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J-GLOBAL

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J-GLOBAL

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DOI： 10.1175/JHM-D-11-013.1

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

The results of bias-correction methods applied to monthly temperature and precipitation data which is simulated by multiple General Circulation Models (GCMs) are compared among GCM outputs in this study. The difference is so apparent that we should care about it when we apply a bias-correction method. There still remains left to not validate enough, we believe the fact explained in this study is useful to choose a bias-correction method for impact assessment.

DOI： 10.11520/jshwr.25.0.90.0

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Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.68.i_217

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.2208/jscejhe.68.I_445

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DOI： 10.2208/jscejhe.68.I_1393

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Blackwell Publishing Ltd  

DOI： 10.1029/2011JD015890

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

The Seto River basin, in the Sameura Dam river basin, is located in the upper Yoshino River in the mountains of Shikoku in western Japan. The management of water resources in the Seto River basin (basin area 53.7 km2) is very important for the water supply to the Kochi City and Takamatsu City. The hydrological model with an hourly time scale for a mountainous basin is applied to the Seto River basin for 20 years between 1991 and 2010. The result was compared with the discharge of Kochi Water Diversion at the Seto River Weir. The results indicated that the model approximately reproduces the groundwater runoff.The relationship between the drought and the seasonal variation of runoff in 10 days average in the Kochi City and Takamatsu City is also studied in this paper. The drought in the Kochi City occurred when the runoff at the Seto River Weir decrease under around 15 mm/10days. It has much difference between the 10 days average rainfall and 10 days median rainfall in the summer season, that caused the drought in the Takamatsu City.

DOI： 10.11520/jshwr.25.0.194.0

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.2208/jscejhe.68.I_1369

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DOI： 10.1007/s10584-011-0197-3

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DOI： 10.1029/2011GL048426

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DOI： 10.1016/j.atmosres.2011.02.002

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DOI： 10.1016/j.watres.2011.02.011

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DOI： 10.1029/2010WR009726

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J-GLOBAL

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jenvman.2010.09.014

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.24.0.119.0

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Language：English   Publishing type：Research paper (international conference proceedings)  

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DOI： 10.1109/IGARSS.2011.6049855

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DOI： 10.1080/02626667.2011.583249

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.24.0.144.0

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3178/hrl.5.73

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.ecoinf.2010.05.005

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jhydrol.2010.07.001

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11269-009-9571-6

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.ecolmodel.2010.03.009

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jhydrol.2009.09.028

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Language：English  

J-GLOBAL

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Language：Japanese  

J-GLOBAL

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.23.0.120.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.23.0.81.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

This study focuses on the parameter estimation of a groundwater parameterization used in global-scale land surface model. Traditional parameter estimation techniques use constant parameter within a basin after best parameters are calibrated and transfer parameter based on similarity of climate. In this study, a grid-scale parameter estimation is formulated based on the precipitation climatology.

DOI： 10.11520/jshwr.23.0.52.0

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1248/jhs.55.860

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.ecolmodel.2009.05.018

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2009GL039006

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2008WR006948

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

In the present study, we developed a global glacier model, HYOGA. Daily time series of glacier mass balance is calculated at 50m vertical sub-grid elevation band at each 0.5-degree grid by the model.<BR>Although the model is only calibrated against the climatology of mass balance observations, the estimated time series of 59-year (1948-2006) global glacier mass balance corresponds well with those of observations. Regional average of glacier mass balance showed that the decrease of glaciers is accelerated after the 1990s.

DOI： 10.11520/jshwr.22.0.7.0

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.5194/hess-13-2241-2009

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Most of the Land Surface Models (LSMs) employ a soil model with a simplified lower boundary condition of free (gravity) drainage or zero flux; hence the interaction between the groundwater (GW) and soil moisture is largely neglected.In this study, we illustrate the effect of parameterization of saturated-unsaturated zone interaction on the prediction of hydrological fluxes by using a coupled LSM-GW model.

DOI： 10.11520/jshwr.22.0.57.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.22.0.35.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.22.0.30.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.22.0.28.0

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Yukiko Hirabayashi, Shinjiro Kanae, 2009, &#039;First estimate of the future global population at risk of flooding&#039;, &lt;i&gt;Hydrological Research Letters&lt;/i&gt;, vol. 3, no. 3/4, pp. 6-9

DOI： 10.3178/hrl.3.6

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.atmosenv.2008.04.008

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1623/hysj.53.4.754

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.atmosenv.2008.03.039

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1175/2007JCLI1854.1

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1623/hysj.53.1.11

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/hyp.6624

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.21.0.54.0

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.5194/hess-12-1007-2008

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.5194/hess-12-1027-2008

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Publisher：Japan Society of Civil Engineers  

Water footprints, or the total consumed water toproduce commodities, were estimated for imported food to Japan, using an integrated globalwater resources model that consists of a physically basedhydrological module and a cropgrowth module. In order to analyze the sustainability of water resources, the model was enhanced to quantify fourmajor sources: precipitation, river, reservoirs, and non-renewable groundwater. The results showed that the water footprint of Japan was 42.7km³/yr. The virtualwater, or the required amount of water that is needed toproduce the imported food domestically, wasestimated 62.7 km³/yr. Therefore, it indicates 20.0 km³/yr of water was saved through international trades. Among the total water footprint, 7.3 km³/yr (17%) was originated irrigation water, and 2.9 km³/yr (6.8%) was non-renewable groundwater.

DOI： 10.2208/prohe.52.367

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.21.0.30.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.21.0.99.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.21.0.84.0

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：English   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

A statistical approach that considers the bias and uncertainty of models is proposed for interpreting the simulated river discharge as a flood risk. A 29-year simulation was performed to estimate parameters of the Gumbel distribution for the probability of extreme discharge. The estimated discharge probability index (DPI) showed clear agreement with observed values. Even more strikingly, high DPI in the simulation corresponded to actual flood damage records. This indicates that the real-time simulation of the DPI could potentially provide flood warnings. This paper also suggests an application using the same statistical method for real-time flood risk prediction that overcomes the lack of sufficiently long simulation data through the use of a pre-existing long-term simulation to estimate statistical parameters. A preliminary flood risk prediction that used operational weather forecast data for 2003 and 2004 gave results similar to those of the 29-year simulation for the Typhoon Tokage (T0423) event on October 20th 2004, demonstrating the transferability of the technique to real-time prediction, which is differently biased.

DOI： 10.3178/hrl.2.22

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Melting Particle is important to estimate rain fall rate in winter season. There are many studies concerning melting particels relating to radar bright band or changes of dielectric constants, but few studies about quantitative observation.We observe rain or meteorological elements since July 2003 at IIS, Tokyo by using Micro Rain Radar(MRR, METEK GmbH Germany). MRR is the small, inexpensive instrument that can detect the radar reflectivity of each Doppler spectrum.In this study, we report the melting situation with comparision MRR observation to calculation of particle melting on 29th December 2004.

DOI： 10.11520/jshwr.21.0.5.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.21.0.98.0

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1175/MWR3418.1

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1175/JHM589.1

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

The predictability of the Indian summer monsoon is examined from an ensemble of 16 atmospheric general circulation model simulations with prescribed sea surface temperatures (SST). The predictability is estimated with a statistical index (Ω) to quantify similarity among the ensemble members. The model simulations show that the predictability of precipitation and the low-level moisture flux during May and June are much larger than that in July and August. The role of land-atmosphere interaction is also focused. During May and June the predictability of soil moisture and near surface temperature are increased by large predictability of precipitation. At the same time, the predictability of cumulus type precipitation could be improved or maintained by positive feedback of large predictability of soil moisture and near surface temperature through atmospheric instability in atmospheric boundary layer. Finally, we suggest two new statistical methods to estimate the phase and shape predictability, and discuss the monthly change of the predictability of the Indian summer monsoon using 3 types of predictability including Ω.

DOI： 10.2208/prohe.51.313

J-GLOBAL

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11269-006-9038-y

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Long-term change concerning the rainfall-runoff response in the Shigenobu catchment was revealed as objects of climate change impact.Annual data-set of the precipitation, discharge and the temperature were investigated in the catchment by the MLIT(Ministry of Land,Infrastructure and Transport) from 1962 to 2002. We analyzed the response relationship between the precipitation and the discharge as the rainfall-runoff event. The result is noteworthy because we could find the rainfall-runoff characteristics change in the case of less than 100(mm/event) as the precipitation that shows the catchment context due to climate change impact.

DOI： 10.11520/jshwr.20.0.19.0

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Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.1007/s11269-006-9038-y

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Language：English   Publishing type：Research paper (international conference proceedings)  

Scopus

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.20.0.61.0

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

Total Runoff Integrating Pathways (TRIP) is a global river routing model which can help to collect and route runoff to the river mouths for the major rivers. In the previous version of TRIP, a simple approach of constant flow velocity is used. In general, that approach is sufficient to model mean long-term discharges. However, to model flood events for example, more sophisticated approach is required. In this study, we implement a variable velocity approach to TRIP. Input runoff data for the experiments are provided by the second Global Soil Wetness Project (GSWP2). We show that the new approach significantly improves the quality of simulated river discharge. At the Pakse station of the Mekong, the correlations between simulated and observed discharges are about 0.94 and 0.83 for the new and the previous approach of TRIP, respectively.

DOI： 10.11520/jshwr.20.0.2.0

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Publisher：Japan Society of Civil Engineers  

A new river discharge predicting system all over Japan utilizingJapan Meteorological Agency's Meso-scale model Grid Point Value (MSM-GPV) datasets isdeveloped. The system, "Today's Japan, " consistsof a land surfacemodel Iso-MATSIRO and a river routing scheme J-TRIP. An Web browser-based visualization interface is also included. This paper presents structure of the system, and manipulates hindcasts for2003 and 2004 andverifies them by using observed discharge data. The results indicate that the systemis robust enough and acceptable for reproducing big flush floods and snowmelt floods, but also find some significant underestimates and shortcomings of reproducing low-flows.

DOI： 10.2208/prohe.51.403

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.20.0.57.0

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

In recent years, torrential rainfall in urban areas during warm seasons has become frequent, and urban effect such as the heat island phenomenon is considered as a possible reason for this trend. In this study, effect of urbanization on torrential rainfall was evaluated through a case study on the Tokyo Metropolitan Torrential Rainfall which occurred from the night of September 4, 2005 till the dawn of September 5, 2005 by using a Meso-Scale Atmospheric Model MM5. As a result, it was suggested that the heat island phenomenon effects the precipitation distribution and intensity of torrential rainfall in urban areas.

DOI： 10.11520/jshwr.20.0.103.0

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Language：English   Publisher：Japan Society of Civil Engineers  

A global integrated water resources model was developed. The model consists of four sub models, a bucket type land surface model, a global river routing model, a process based agricultural model and a reservoir operation model. The model was designed to work with near surface meteorological data and currently available global grid-based digital GIS data. It enable us to conduct 1) monthly or daily assessments of global water supply and demand, 2) numerical experiments concerning the interaction of human activity and land hydrology, 3) analyses on global water balance components in which energy and water balances are perfectly closed. In the former part of this report, the structure of model and the simulation setting are described. In the latter part, the performance and limitation of the model are discussed using the results of a preliminary global simulation.

DOI： 10.2208/prohe.50.529

CiNii Books

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Language：English  

DOI： 10.1126/science.1128845

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1175/JHM511.1

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1175/JHM510.1

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jhydrol.2005.11.011

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.gloplacha.2005.12.007

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1175/JCLI3686.1

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Language：Japanese   Publisher：水文・水資源学会  

2005年はチェンマイにおいて40-50年来の規模の洪水が5回発生し、同地域に甚大な被害をもたらした。筆者らは当洪水および洪水予警報システムを調査するため、2005年11月から1ヶ月間チェンマイにて現地調査を行った。同洪水による浸水地域は、人工堤防がないため地形にほぼ対応しており、河川水位から浸水被害が予測できることが分かった。また絶対的な観測所数の不足は見られず、水位相関法を用いた予測は高い相関を示していた。しかし一方で、リアルタイムデータを得ていないためデータ報告の谷間に水位上昇した場合に予警報が遅れるなどの問題点を抱えることが明らかになった。さらに、洪水警報発令権のある内務省管轄機関はタイ王立灌漑局やタイ気象局から情報を受け取るという立場にあるため発令判断能力は乏しく、後者にとって機関内での洪水予測の優先度は低いために予算や人員を割けない等の問題点も見られた。

DOI： 10.11520/jshwr.19.0.34.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.19.0.118.0

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：Japanese   Publisher：水文・水資源学会  

水資源に対する地球温暖化の影響予測のために、農業用水を時間的・空間的に高解像度で推定する必要がある。また近年、水資源利用における天水の重要性が指摘されており、灌漑水に対して天水の寄与分がどの程度なのかを知ることは重要である。そこで、農業プロセスモデルSWIMを用いて、2001年のGCMによる気象予測データを入力値とする必要水量の推定を全球グリッドベースで行った。灌漑用水を必要なだけ与えた場合と、天水のみで栽培した場合の二通りのシミュレーションを行い、両者における栽培期間中の農地からの蒸発散量を比較して、天水と灌漑必要水の構成割合を求めた。さらに、地球温暖化が生じた場合におけるこれらの値の変化を、2050年と2100年の気象予測データを用いて推定した。この結果、地域によって変動のしかたが異なる様子が明らかになった。今後は、実測値との比較などを行い、精度について検証してゆくことが課題となる。

DOI： 10.11520/jshwr.19.0.22.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

This paper presents a simple method for including elevation into spatial interpolation of annual rainfall in a 4000 km2 region located in Ardebil province in the North-West of Iran. We considered an elevation factor in calculating distance in three-dimensional Inverse Distance Weighting (IDW) method. The effects of using various amounts for this factor on obtained distributed annual rainfall map have been evaluated.

DOI： 10.11520/jshwr.19.0.87.0

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Language：Japanese   Publisher：水文・水資源学会  

本研究では，タイ内陸部を中心にプレモンスーン期の陸面熱フラックスを，NCEP/NCAR客観再解析による風・水蒸気場・および潜熱・顕熱，降水量，熱フラックスの観測データ（Tak）を用いて解析した．モンスーンオンセット前の3月中旬からすでに潜熱フラックスが卓越し続けており陸面が湿っている．また2月中旬から潜熱フラックスが顕熱フラックスを上回る状態が時々現れる．潜熱フラックスが卓越している時期の合成図解析によると，中国南部からタイ内陸部，カンボジアにかけて潜熱フラックスが顕熱フラックスより大きい地域が広がり，インドシナ半島内陸部を中心とする上層のトラフが解析される．さらに可降水量がタイ内陸部を中心に増加しており，陸面からの潜熱フラックスによる大気の湿潤化への寄与が示唆された．インドやミャンマー内陸部ではモンスーンが開始するまで潜熱フラックスは増加せず，タイ内陸部と特性が異なる．

DOI： 10.11520/jshwr.19.0.6.0

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Language：Japanese   Publisher：水文・水資源学会  

地球温暖化により世界の水資源に顕著な影響が出るのではないかと懸念されている。この影響を評価するには降水パターンの変化といった水の供給側の変化に加えて、乾燥化（湿潤化）に適応するための灌漑の増加（減少）といった水の利用側の変化も同時に考慮する必要がある。また水の需給には大きな季節変化があることから年単位以下の時間スケールでの評価が重要である。これまでにも温暖化の水資源への影響を定量的に評価する試みが数多く行われてきたが、水需給の表現が不十分であったり、季節変化を無視していたりする問題があった。そこで詳細な水需給過程が表現できる花崎ら（2006）による全球統合水資源モデルと高解像度の温暖化予測気象データ（K1データ）を利用することにより、温暖化時の水資源評価を試みる。

DOI： 10.11520/jshwr.19.0.21.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

DOI： 10.11520/jshwr.19.0.116.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

GAME (GEWEX Asian Monsoon Experiment) had been conducted under the frameworks of WCRP/GEWEX from FY1996 to FY2004. Herein, We introduce the new framework & program name as MAHASRI (Monsoon Asian Hydro-Atmosphere Scientific Research and Prediction Initiative). MAHASRI is addressed a succesor of GAME, however its extended into ocean studies and so on.

DOI： 10.11520/jshwr.19.0.63.0

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Language：Japanese   Publisher：水文・水資源学会  

DOI： 10.11520/jshwr.19.0.98.0

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：日本リモートセンシング学会  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2004JD005492

Scopus

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2004JD005492

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2004JD004825

Scopus

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1029/2004JD004825

Web of Science

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Language：Japanese  

DOI： 10.2208/prohe.49.1495

J-GLOBAL

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Language：Japanese  

Yukiko HIRABAYASHI, Shinjiro KANAE, Taikan OKI, 2005, &#039;Long-term Variation of World Terrestrial Water Cycle in 20th Century&#039;, &lt;i&gt;PROCEEDINGS OF HYDRAULIC ENGINEERING&lt;/i&gt;, vol. 49

DOI： 10.2208/prohe.49.409

J-GLOBAL

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Other Link： http://orcid.org/0000-0001-5693-197X

Language：Japanese   Publisher：Japan Society of Civil Engineers  

It is shown that a similarity parameter has new mathematical structure. Heretofore, the correlation coefficient is used for quantifying the correlation relationship between two ensemble members. Koster et al&lt;SUP&gt;1&lt;/SUP&gt; introduced a statistical parameter, called Ω to quantify the similarity among several ensemble members with calculating the ensemble numbers and the two types of variances. However the mathematical structure of Ω had not been revealed in their studies. The present authors applied to derivate Ω for understanding the mathematical meaning of it. As results, we could have a knowledge that Ω consists of mainly two terms. One is the average value of cross correlation coefficients (ACCC) across all ensemble members. Another is the similarity of the mean value and the variance across all ensemble members. Therfore, the authorscan conclude that Ω shows the similarity of the &#039;shape&#039; of all ensemble members and the mathematical characteristics is more capacious than the correlation coefficient. The paper ends with some remarks on the mathematical characteristics of &#039;as a new evaluation methodology for the predictabity of numerical forecast.&#039; in monthly or seasonal time scale.

DOI： 10.2208/prohe.49.1

J-GLOBAL

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Language：English   Publishing type：Research paper (international conference proceedings)  

Scopus

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Language：Japanese   Publisher：水文・水資源学会  

第二全球土壌水分プロジェクト（Second Global Soil Wetness Project: GSWP2）は高精度の気象データと世界最先端の陸面過程モデルを利用して陸面状態量（土壌水分、積雪被覆）や陸面フラックス（蒸発量、流出量）のグローバルデータ構築を目指す国際プロジェクトである（Dirmeyer et al. 2002）。このGSWP2の枠組みを利用し、全球日単位の流出グリッドデータを構築することを目的とする。現在GSWP2には世界の１５の気象研究機関が参加し、それぞれが出力データを提出している。しかし全く同じ入力データが与えられたにも関わらず、出力データには大きなばらつきがあった。また入力データ（気象データ）にも誤差やバイアスが含まれていることが明らかにされてきた（Tanaka et al., 2005）。そこで感度実験の結果を利用することで気象データの誤差やバイアスの影響を除去しながら各モデルの流出量の特徴を明らかにし、その知見をもとに１５の出力データの最適な組み合わせを見出し、流出グリッドデータを構築する。

DOI： 10.11520/jshwr.18.0.69.0

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Language：English   Publishing type：Research paper (international conference proceedings)  

Scopus

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Language：Japanese   Publisher：水文・水資源学会  

近年日本各地で豪雨による洪水が頻発している．2004年は10個の台風が日本列島に上陸してこれまでの上陸回数の記録を更新し，死者行方不明者が200人を超えるなど，豪雨・洪水による被害がここ数年で最悪の年となった．豪雨に対して気象庁はスーパーコンピュータを用いて雨量を事前に定量的に予測し，周辺自治体や住民に警戒を呼びかけている．しかし，豪雨による河川水位は定性的な予測にとどまり，定量的な予測は行われていない．洪水ハザードマップも作成されてはいるが特定の河川や地点・地域に限定されており，充分に機能しているとは言い難い．このため周辺住民にとっては洪水危険予報の信憑性はそれほど高くなく，避難判断の遅れによる洪水被害の拡大が懸念されている．そこで，本研究の目的を「気象予報データから日本全域で河川流量の変動を定量的に予測する」とし，日本全域での河川流量予測システムを開発して，河川流量の定量的な予測の実現可能性について検証を行った．

DOI： 10.11520/jshwr.18.0.73.0

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Publisher：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

The present-day and future extremes on river discharge simulated by a relatively high-resolution atmospheric general circulation model (GCM) were analyzed. Validation of the GCM experiment with gauge observations and off-line data showed that the drought frequencies were well replicated in the model. Future projection of the model under the IPCC-A1B scenario showed increase of flood frequencies in south east and northern part of North American continent, east Europe, Scandinavian Peninsula, Indus river, south part of China, Australia, south Africa and south part of South American continent. Frequencies of the drought were increased in south west part of North American continent and South American continent, Mediterranean region, south part of Africa, middle Asian countries, north part of India, Indochina Peninsula, and Australia.

DOI： 10.11520/jshwr.18.0.70.0

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Publisher：Japan Society of Civil Engineers  

A global river discharge simulation is conducted taking into account irrigation water intake and reservoir operation. The monthly irrigation water demand is calculated globally by a modeling approach, and it is withdrawn from the river section in the same calculating cell. Four simulation runs (with/without irrigation intake × with/without reservoir operation) are compared, to clarify the effect of irrigation water intake on the river discharge simulation.<BR>In the latter part, irrigation water demand and supply is assessed in monthly interval for nine basins in the world. The result suggests that the irrigation water intake significantly decreases the river discharge in specific period and affects the water resources in the whole river basin.

DOI： 10.2208/prohe.49.403

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Language：English   Publishing type：Research paper (international conference proceedings)  

Web of Science

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Language：English   Publishing type：Research paper (international conference proceedings)  

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2151/jmsj.2004.1315

Web of Science

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1126/science.1100217

Web of Science

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Language：Japanese   Publisher：Japan Society of Civil Engineers  

The extent of the coupling strength between the land and the atmosphere controls the behavior of the atmospheric processes. Precipitation is induced by the soil moisture variation. K02 focused on the coupling strength between four AGCMs. It is mentioned that the coupling strength has much model dependence. The authors are participating the GLACE (Global Land-Atmosphere Coupling Experiment) which follows the K02 experiment. Before undertaking the GLACE experiment, it is conducted the K02 experiment to compare or evaluate our AGCM (CCSR/NIES) result with K02 results. As a result, the coupling strength on the precipitation process is much weaker than the latent heat flux. This is the same characteristics in three of four models in other K02 participants. Moreover, the coupling strength on the latent heat flux shows the relatively high value over the Central Eurasia or the North America.

DOI： 10.2208/prohe.48.223

J-GLOBAL

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2151/jmsj.82.241

Web of Science

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Language：English   Publishing type：Research paper (international conference proceedings)  

Scopus

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