Most of the past studies on the levee destruction are determinism that for the different flood conditions the levee is failure or not failure. However in the real environment, there are a lot of uncertainty factors that would affect the analysis result of the levee stability very seriously. In this study, the authors would consider the variability of soil parameters of levee and propose the new idea for the reliability evaluation of levee during floods by using the probability theory.
 In consideration of the different water level conditions, the probability of safety factor of levee can be estimated. When the levee is completely saturated, the safety factor is 80% smaller than 1.2 with considering the uncertainty of the soil parameters in the levee with 7.5 m height. And another water levels, like 7.50 m, 7.25 m and 7.0m is be estimated, here the high water level is 7.0 m assumed.
 In conclusions, with considering the variability of the soil parameters, the safety factor of levee is a distribution. Furthermore the driving force and resistance force of levee can be summarized as the reliable design analysis. Finally in this study, the risk of flood (including of levee destruction and overflow) can be evaluated with the change of water level.

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 River flow discharge is commonly estimated from measured water surface velocity with floats, or noncontact current meters, or water surface slope; eg. Slope-area method is introduced in International Organization for Standardization (ISO, 1992) with assuming rigid-bed and constant Manning's roughness coefficient. On the other hand, fluvial hydraulics community indicates that the bed roughness composed of grain roughness and form roughness, and that form roughness depends on meso-scale bed forms. These kind of studies were well verified by experimental studies, and contributed to theoretical studies, though it is not easy to verify in the river reach. Observations during flood had been considered as almost impossible, because of high velocity and water surface fluctuation. However, due to development of the measurement technique, especially a tethered boat mounted ADCP, flood observational results have accumulated data of mentioning phenomena about fluvial hydraulics about bed evolution and the roughness change. Summarizing above mentioned aspects, it is inferred that the fluvial characteristics of river channels are major components of uncertainties in estimating flow discharge. The authors in this paper describe estimation of the flow discharge under erodible condition.
 Based on the ADCP measurements, the authors investigate how the fluvial characteristics under erodible bed condition affect to estimate flow discharge using the following time-series data: flow area, bed evolution, the Manning's coefficient, and flow discharge obtained by ADCP and Slope-area method. As a results, flow discharges obtained by ADCP and Slope-area method were identical excepting peak flow discharge period, though river bed and bed roughness fluctuated in great extent. The authors also discuss about not-identical parts at peak using relation between hydraulic resistance and micro-bed form. As a results, when the bed roughness changes due to deformation of bed form from duen to transition, Slope-area method always overestimate discharge value.

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 Improving the accuracy of peak runoff height estimation for flood risk reduction purpose is one of the research targets in hydrology. Peak runoff height is generally simulated by hydrological models deterministically. A recent study suggested that the rainfall-runoff system can be expressed as a stochastic differential equation by adopting the Fokker-Planck equation in association with rainfall pattern. The objective of this study is to estimate the uncertainty of peak runoff height by considering uncertainty of effective rainfall through the water holding capacity in addition to the uncertainty of rainfall pattern. Results show that the uncertainty of peak runoff height increase with the increment of uncertainty associated with rainfall pattern, whereas uncertainty of water holding capacity needs to be considered in the quantification of the uncertainty of peak runoff height.

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 River floods are natural disasters that affect millions of people every year. In addition, vast areas of floodplains used for cattle farming are inundated annually, and animals often drown. Depending on the floodplain characteristics, the floods can last for several days or even months. Even if the water depth is not sufficient to drown cattle, the long exposure to flood water may cause diseases. Thus, it is important to define safe zones and to identify safe routes for cattle to reach such zones.
 This study proposes flood evacuation zones for cattle in the Llanuras de Mojos (in the Bolivian Amazonia), based on the results of a two-dimensional flood simulation using a flood inundation model. Flood simulations provided the daily variation in the extent and depth of flooding. These results enabled flood hazard zones to be defined for cattle on different days. It was found that the left margin of the Mamore River was the most hazardous zone, with flood depths that were likely to drown cattle. The best evacuation route was identified as the right bank of the Mamore River located on the northern edge of the city of Trinidad.

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 Floods in Indonesia are considered to be one of the major natural disasters. Jakarta City in Indonesia has experienced many floods in the past, such as those in 1996, 2002, 2007 and 2013. In this paper several problems causing the floods in Jakarta were discussed and a flood inundation model was applied to the 2007 and 2013 flood events. Also, a counter measure to increase the flood flow carrying capacity of the Ciliwung River was evaluated by a numerical simulation. As a result of analysis, it was found that the applied flood inundation model relatively well reproduced the flood inundation situation in Jakarta. Further, the counter measure that increased the flood flow capacity of the target sections by 150% was found to reduce the flood inundation volume by nearly 15%. However, considering the fact that there are still many areas remaining inundated, it would also be needed to investigate the effects of other rivers and several other factors contributing to flooding in Jakarta.

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 The purpose of this study is to develop a new optimum operation system for large-scale reservoir on science-based which can be easily put into practice in developing countries. The Bhumibol and Sirikit reservoirs in the Chao Phraya River basin (CPRB) in Thailand were selected for this study. After the CPRB had a massive flooding in 2011, the Thai government has been planning new watershed management for the CPRB.
 This paper proposed the new useful reservoir operation method. This proposed method used new optimal rule curve determined by historical hydrological data. This paper verified the method using historical hydrological data from beginning of reservoir operation to February in 2015. As a result, the proposed reservoir operation method contributed stabilization of storage volume with minimizing risks of flooding and drought. The proposed reservoir operation method also contributed discharge volume for the irrigation in dry years.

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 The purpose of this study is to clarify the effect of reservoir operation on the flow regime in the lower watershed using numerical simulation. Using the simulated river discharge data, the spectrum characteristics of river discharge data was studied.
 As a result of numerical simulation, The spectrum of daily discharges available information was analyzed by using the fast Fourier Transform for daily discharges in Nakhon Sawan city and immediately downstream the Bhumibol reservoir. The river flow in Nakhon Sawan city has a periodic characteristic of 7-days, and the released water from the Bhumibol and Sirikit reservoir' have a periodic characteristic of 7-days. The reservoir operations affected the hydrological cycles considerably. Two large scale reservoirs have been affected to the flow regime in the lower Chao Phraya River basin of Thailand using the historical discharge data. As mentioned above, the river flow regime at least around 400km downstream large scale reservoir could be affected by the reservoir operation.

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 It has been 100 years since the flood prevention works began in the Ishikari river basin, the northern island Hokkaido in Japan. The purpose of this activity was to reduce groundwater levels up to 90 cm in addition to the flood control management because many regions in the Ishikari river basin were covered by peat and wetlands. This study investigated the change of groundwater level in association with historical information of land subsidence and field observation over some areas of paddy field where were used to be natural ponds or wetlands. The estimation method for the change of groundwater level was applied to a method which was used to investigate embankment subsidence in peat lands. Our results showed that the estimated change of groundwater level at several areas is comparable with observed values by our field survey.

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 Understanding the gap between a target ecological state of a river and its current state is the first pivotal step in the process of nature restoration. The target rivers in this study had many native species and few alien species in the past. But feasible target setting posed a challenge due difficulties in obtaining historical information of small and medium sized rivers in rural area. For this reason, river classification using topographical and geological features was done to clarify the characteristics of each river group. But some rivers had many alien species than others despite belonging to same characteristic group. To find out the reason, the water quality and the number of river structures were compared. The results showed that poor water quality and placement of structures in the steep downstream section of the rivers contribute to creating a suitable habitat for alien species.

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 Measurements on non-use values of environmental qualities are important for decision-making on projects. Non-use values are frequently measured by using stated preference data which may include biases. Thus, there is possibility that measured values on non-use would include other values such as use values. The purpose of this study is to examine a model to decompose use and non-use values by using both the stated and revealed preference data. Data on both trips for wetlands in Hokkaido and willingness to pays for improving biodiversity in the wetlands were used. Results indicated that the use value was about 146 yen per a year and non -use value was about 193 per a year in 339 yen per a year which was measured as the non-use value by using stated preference data only.

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 Sarobetsu river and Panke swamp which connect to Teshio River are the northern limit of Corbicula Japonica fisheries in japan. However, Fish catches continued to decrease and it is necessary that the effecttive measures are taken for resource conservation.
 In this study, we cleared the hydraulic structure of Sarobetsu River, and analized the relationship between fresh water clam habitat and hydraulic stracture. First, we performed continuous flow observation at plural points of Sarobetsu River, and examined water balance of Sarobetsu River. As a result, it was found that the outflow is dominant in Sarobetsu River, and then salt water intrusion is suppressed Also it was found that the dilution of salt water proceed after summer season because of preferentially freshwater supply into Panke swamp.In view of the salt supply to Panke swamp, flow rate of Sarobetsu River is important. Flow rate of Sarobetsu River is in increasing trend since 1980, as response to fish catches showed a decreasing trend. Flow rate increase is dependent on rainfall intensity, a change in rainfall condition of near 30 years is presumed to be a main cause of Corbicula Japonica decrease.

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 Cross sectional profile, hyporheic flow velocity and spawning redds distribution were surveyed, and hyporheic flow was also calculated, to understand influence of bed morphology, alluvium thickness and groundwater level along river on hyporheic flow distribution and chum salmon spawning environment. Water surface elevation distribution on the field bed surface, alluvium thickness and groundwater level beside the river were considered in the hyporheic flow calculation condition. The results revealed that welling up hyporheic flow velocity was low and little spawning redds was found in thin alluvium section. On the other hand, in the section which has characteristics with thick alluvium and higher groundwater level than river water level, groundwater flowing into river bed and welling up with hyporheic flow which was caused by a bar morphology, was confirmed. In the case that groundwater level were lower than river water level, hyporheic flow flowing out from river bed and reduction of hyporheic flow welling up were confirmed. These results suggest that thick alluvium thickness, hyporheic flow caused by bed morphology and ground water intrusion into river bed are satisfactory for spawning environment because of various length of hyporheic flow path exist.

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 The purpose of this study is to clarify actual state and mechanism of saltwater intrusion of artesian well in the edge of the Kurobe River alluvial fan. The long term and continuous water quality observation has been carried out for “Sho-zu of Shimizu-an” which is one of most popular springs located in Ikuji district, Kurobe city. As a result of observation, the saltwater intrusion of the artesian well has been progressing drastically for the last 10 years. Maximum chloride ion concentration was 157 mg/L observed in August 2013, if saltwater intrusion will progress it will be too difficult to drink. The tide level of Toyama bay had an uptrend with statistically significant and the seasonal change in EC agreed very well with the tide level of Toyama bay. The causes of the saltwater intrusion of artesian well were decreasing of groundwater level through the whole are of the Kurobe River alluvial fan and increasing of the tide level of Toyama bay.

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 The flow regime in the Uchikawa River (UR) where is located in Toyama Prefecture is extremely intricate because the channel network had been reformed. Especially, the west of the UR has been controlled by the government in order to manage water quality. The velocity distribution had been observed using the ADCP (acoustic Doppler current profiler) for 3 years in the UR. The water level, water temperature and electric conductivity had been measured at the same time. We had 88 days observation data.
 As a result of the observation, 57 distinct salt wedges were observed from 17:00-18:00 every time because of operation rule of the pumping station for water quality management. Moreover 37 distinct salt wedges had backward current in all layers near the tip of salt wedges. There has never been an observation like this before.

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 The purpose of this study is to clarify current situation and the long-term change of the groundwater environment in the Kurobe River alluvial fan (KRAF). The groundwater level and water quality observations in the KRAF were carried out in 2012 and 2013. This study compared the results between the field observation in 2012, 2013 and in 1990 and 2002. As a result of the field observation in 2013, groundwater level in February (winter) was approximately 2-5 m lower than that in August (summer) in whole alluvial fan because there were no irrigation water in the paddy and the discharge of the Kurobe River was too small. It is clarified that the KRAF has three different groundwater flow systems. As groundwater level, EC, water temperature, pH and ion components in 2012 and 2013 were compared between the observation in 1990 and in 2002, there were not large difference. Thus, the groundwater environment has been changed in the past 23 years in the KRAF.

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 This research paper aims to estimate the eutrophication of dam reservoirs for drinking water caused by future climate change, and to evaluate the impact against water utilities and the effectiveness of adaptation measures in a national scale. Based on two emissions scenarios, average annual Chl-α concentrations of surface layer water at present and in the future were estimated in 37 objective dam reservoirs, and affected populations by the change in water quality were calculated based on the water intake amount of 54 water utilities that take water from the 37 dam reservoirs in each region. It was estimated that a Chl-α concentration tends to increase till the 2100s. Although the ratio of affected population among supplied population has increased till the 2100s, the affected population will reach a peak in the 2050s and will decrease after the 2050s due to natural population decline in Japan. The research presented that, as an adaptation measure, an introduction of circulative aeration facilities in dam reservoirs can decrease the affected population and can reduce the cost of advanced water treatment system construction.

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 Future projection and assessment of water quality changes of water resources reservoirs in Japan which will be possibly caused by climate change and watershed environmental change, such as population decrease, were conducted in this study. The projection method developed in this study was composed of three components: vertical 1-dimensional models of water temperature and water quality prediction in reservoirs and a statistical model of water quality loading from watershed. As a result from simulations, phytoplankton biomass in reservoirs will be more affected by potential decrease of nutrients loading from watershed with the decline of watershed population than atmospheric temperature rise. However, our analysis suggested that reservoirs located in northern part of Japan where current population density is lower than average might face the possibility of water quality deterioration around the end of this century.

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 The tool to simulate CO₂ emission reduction from transport sector in ASEAN by introduction of low carbon transport policies from a view point of long-term was developed. The tool is supposed to be utilized to develop original long-term action plan by public officials and researchers in ASEAN.
 Various data sets for evaluation and several policy packages and its introduction effects are stored in the tool, and then users are able to evaluate CO₂ emission reduction effect easily to select appropriate policy packages and input necessity items.

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 This study clarifies the factors to determine risk perception of climate change and attitudes toward adaptation policy by analyzing the data collecting from Internet survey to the citizens in rural areas and farmers. The results indicate the followings: 1) more than 60% of the respondents perceive some sort of risk of climate change, and most people are awaken to wind and flood damage. and damage to daily life. 2) morer than half of the respondents recognize that adaptation and protection measures are preferable, whereas more than 70% of the respondents assume to accept adaptation policy as self-reponsibility, 3) the most significant factor to determinane attitude towerd adaptation policy is risk perception that is furthermore determeined by experience of disaster and social capital.

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 Although global integrated assessment models have been used for the long-term climate mitigation analysis, they are rarely evaluated their predictability. This article made an experiment of hindcasting by using AIM/ CGE (Asia-Pacific Integrated Model/ Computable General Equilibrium) which is one of the IAMs and evaluated the model results against to the historical statistics. The historical simulation is made under exogenous GDP, population and energy technological progress assumptions as well as future simulation and the energy consumption is compared with statistics information. There are three main findings. First, global aggregated information tend to show high reproducibility and for example, total energy primary energy is about 10% discrepancy to statistics. However, those of disaggregated regional results are lower than that and especially low income countries' results tend to be low. Second, as years go past, the reproducibility of primary energy supply and final energy gets lower. Third, reproducibility in terms of energy sources, oil and natural gas, and in terms of sectors, transport sector showed lower reproducibility than others and there are rooms to improve the model in these components.

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 Cambodia had changed from a net carbon sink in 1994 to a net emitter in 2000 where the highest contributor of GHG emissions was land use change and forestry (51%), followed by agriculture (45%), energy (4%), and waste (less than 1%). However, Cambodia has not formulated a concrete plan for GHG mitigation in the Agriculture, Forestry and Other Land-Use (AFOLU) sector. Therefore, it is an appropriate time to propose a scenario to assess GHG emissions and mitigation potential for this sector in Cambodia. This study applies AFOLU Bottom-up Model (AFOLU-B) to estimate GHG emissions and mitigation potential based on assumed socioeconomic indicators and on ongoing policies for the AFOLU sector through taking several constraints under mitigation cost and measures into account. The results yield that GHG emissions will change from a net carbon sink (0.94MtCO₂eq.) in 2010 to a net emitter (13.98MtCO₂eq.) in this sector in 2050. In the agricultural sector, the most effective mitigation measures are applied with the cost of less than 10US$/tCO₂eq.; rice cultivation contributes the biggest share (87%), while in the land use change and forestry sector, the most plausible mitigation measures are applied with the cost of less than 50US$/tCO₂eq.; reduced impact logging generates the largest mitigation potentials (99%) because of limited available land to apply plantations in the future. These findings are expected to provide insights for decision-makers to formulate climate change mitigation policy for the AFOLU sector.

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 Atmospheric blocking causes extreme weather condition in the middle latitudes. A previous study mentioned that the winter blocking will shift northeastward over the North Pacific for future climate. This study investigates about the effects of the shifting of winter blocking on extreme events over surrounding Japan by utilizing Coupled Model Intercomparison Project Phase 5 datasets. In the 20^th century climate, the winter blocking over the sea of Okhotsk tended to occur with extreme low temperature days over surrounding Japan, and it was predicted that the blocking will reduce in the future climates. It is revealed that the low temperature days over Japan will tend to occur with wide area and will decrease with blocking over the sea of Okhotsk in the future climate.

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 In the Aral Sea Basin, serious drought was induced by huge-scale irrigation projects. Toward sustaineble water management, impacts of climate change on water resource and water demand should be quantitatively estimated to provide a scientific basic information for the rational planning.
 In this study, terrestrial water circulation model was applied to project future water resource and demand. It is mainly consist of land surface model SiBUC (Simple Biosphere including Urban Canopy). In its irrigation scheme, local irrigation rule was reflected through in situ measurement on testing farms in Uzbekistan and furrow irrigation can be considered which is generally selected in this basin. The meteorological data for the model input are from Meteorological Research Institute atmospheric general circulation model (MRI-AGCM3.2S) based on A1B scenario. Spatial resolution is about 20km and time resolution is one hour. Since the GCM projected that both temperature and precipitation will increase in the whole basin, future drought situation should be quantitatively analyzed by physical model.
 As a result of the analysis, water resource will not change since increment of precipitation will consumed by evapotranspiration increase and little water will additionally flow out as surface runoff. On the other hand, water demand will increase due to temperature rise especially in the arid region. In the limitted area in mountainous region, precipitation increase reduces water demand for irrigation. Comprehensively, drought situation in this basin will increase under the future climate.

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 Human activities such as water withdrawal from rivers and groundwater for irrigation affect not only the global water cycle but also the atmospheric circulation. Previous studies have investigated the impacts of human activities on the terrestrial water cycle by using hydrological models or offline land surface models (LSMs). However, less attention is paid on the impacts of human water management on land-atmosphere interactions. In this study, we coupled an atmospheric general circulation model (AGCM) with the LSM of Pokhrel et al. (2015) that is integrated with irrigation and groundwater pumping schemes. The main objective of this study is to quantify the influence of human activities on the global water cycle. Model indicates declining water table depth in the Ogallala aquifer where the withdrawal from groundwater for irrigation the irrigation is large. Results also show that the evapotranspiration over Pakistan and India where the irrigation water demand is higher than in other the regions tends to increase, and the precipitation over the eastern parts of those regions also tends to increase.

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 The synthesis report of the IPCC fifth assessment report (AR5) stated that warming of the climate system is unequivocal. In cold and snowy regions, snowmelt water cover water demand. Therefore, the risk of water shotage might be increased by the climate change.
 In this paper, we studied the effects of climate change on the Jozankei Dam during snowmelt season. As results, it is found that fluctuation of the amount of snow and snowmelt water might be increased and heavy rain might be occured at the last half of snowmelt season in when percentage of storage is high in the future climate.

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 This study proposes a procedure to extend The Dynamic Integrated Climate-Economy model 2013R (DICE2013R) to enable the simulation of a new framework for climate change studies (Shared Socioeconomic Pathways (SSP)), and tentatively assesses long-term climate stabilization targets, considering the possible range of climate sensitivity. The results show that if a higher than actual climate sensitivity is assumed in the planning stage, a greater reduction in industrial CO₂ emissions will be required to achieve the 2°C target, and thus the climate change costs are also larger. In contrast, with a lower than actual climate sensitivity assumption, a lesser reduction in industrial CO₂ emissions will be required. Climate change researchers and policymakers need to balance the designation of climate policy and the uncertainty with respect to climate sensitivity, to avoid potential losses when climate change policy is implemented. The study also identified the mitigation and adaptation challenge levels, as defined in the SSP framework.

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 The high tropospheric O₃ concentration was observed in 8^th-12^th May, 2009 in Yakushima Is. In order to evaluate the atmospheric pollutant long-range transport and its origin, O₃ and particulate matter samples was collected during 9^th to 12^th May, 2009 in Yakushima Is. The back trajectory analysis indicate that the variation of O3 concentration was related to the air mass passing rout. In other words, the high O₃ concentration was observed when the air mass comes from the Asian continent and the low concentration of O₃ was observed when the air mass comes from the Pacific Ocean. It suggested that the origin of high concentration of O₃ were the NO_X and VOCs which is emitted from the China continent. These chemicals were changed into O₃ by the photo chemical reaction in the atmosphere during the long-range transport process to Yakushima Is. In particulate matter, relationship between NO₃^-, nss-SO₄^2- were observed in small particle of PM_1.0-2.5 and 1μm>PM fraction. On the other hand, correlation was not observed in PM_1.0-2.5 fraction. The high correlation was observed between Fe and Al in PM_2.5-10 fraction and the ratio (0.6) shows the same as the Asian dust. This result suggests that the PMc fraction may originate from the natural source in China continent, and the PM_1.0-2.5 and 1μm> fraction is originated from the anthropogenic source.

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 Elevated particulate matter (PM) concentrations in urban atmosphere in Japan are associated with fine particles emitted and/or formed in an urban area and those transported from the Asian continents. It is thus important to know each contribution for the improvement of urban PM pollution. In this study, a new approach to evaluate transboundary PM pollution is developed based on the measurement of optical properties of fine particles such as SSA (Single Scattering Albedo) and B/N ratio (absorption coefficient/fine particle number concentration), and applied to Sapporo, Japan. The results suggest that during the observation period (June - Dec. 2014), transboundary pollution contributed more than 70% to the PM concentrations in Sapporo, and that transboundary pollution contribution has a seasonal variation with a decrease in summer and an increase in autumn. The approach is expected to serve as an important tool towards effective measures for PM pollution control in Japan.

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 This paper attenpts to apply an online deliberative experiment to a issue of wooden biomass utilization. We have screened 34 stakeholders on the issue and provided them with expert konledge. Then we have analysed their attitude change by questionnaire data of before and after deliberation and by text mining of discourse. The results shows that i) proponents of wood biomass as general term has increased slightly after deliberation, ii) as for intermediate and demand side, ther emerged the group that would shoulder a burden morer than the present and the group that could not go along with, and for supply side, there emerged the group that are involved in if it would turn a profit iii) the effect of this experiment indicates that the most participants were able to express their opinions and collected information autonomously and then interactied each other.

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 While a small hydroelectric generation is one of the natural power generation without greenhouse gas emission, there are a lot of optimum sites for it in Japan. The reasons may be explained by the inadequate observation flow data and the difficulty of evaluation of the economic viability. We simulated stream regime through the use of runoff analysis model (HYDREEMS), which had high accuracy in case-study stream regime. Finally, through the use of HYDREEMS and electric generation unit price evaluation system, we conducted following electric generation unit price evaluations in two cases; 1) detection for optimal sites relationship between flow intake and electric generation plant, 2) comparison with two cases which were calculated by the use of sand-trap dam or not as an intake dam respectively.

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 This study estimated rainfall intensity using the time difference in the detection of rainfall between a X-band multi-parameter radar (X-MP radar) and rain gauges. The rainfall intensity was calculated by the time-difference in the detection of rainfall and an equation used to determine the terminal velocity of raindrops. This diameter can be considered to represent the height between ground level and the lower atmosphere, which the X-band MP radar detects. The determination of rainfall intensity (both 1 min and 10 min temporal scales) by X-MP radar was improved at ten raingauge stations which are located 22 to 42 km from the radar site.

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 This research discuss relationship between sea surface temperature in the Pacific Ocean and the Indian Ocean and climate Southeast Asia. We used Empirical Orthogonal Function analysis and K-means method for analysis and classified 5 group based on the characteristics of sea surface temperature in the Pacific Ocean and the Indian Ocean. Then we investigated precipitation, the number of typhoon and tracks for each group. The group including the year of 2011 has high sea surface temperature in the Pacific Ocean, the Indian Ocean and the Atlantic Ocean. At that time the ratio of the number of the typhoon in the Northwest Ocean Pacific that attack the Southeast Asia is 1.4 times the average one. This research indicate predictability of the typhoon number from large scale sea surface temlperature anomalies.

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 Large-scale watersheds need integrative water management because large-scale watersheds have a large variety of water-related issues like flash flooding, drought, quality, heavy rainfall etc. The purpose of this study is to propose both flood and drought risk potentials in large-scale watersheds for decision makers and/or administrators. In this paper, we discuss the flood and drought risk potentials based on 45-year rainfall data in the Chao Phraya River basin, Kingdom of Thailand. The Chao Phraya River basin was divided into 58 sub-basins, from which we estimated area-averaged rainfall using 873 rainfall stations data.
 We can identify the sub-basins which have high potential of heavy rainfall and drought. It is important to recognize that the whole Chao Phraya River basin has a tendency to drought during 1952-1997.
 Precipitation is the most important factor which decides the potential of water-related disaster like flooding and drought, and then we need to organize the behavior of precipitation statistically and stochastically.

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 In recent years, it has been pointed out that climate change due to global warming has effected to the scale and form of rainfall. In Japan, many regions have experienced floods, landslides from unusually intense rains, and much of the country has seen record-breaking rainfalls. By 20^th August 2014 , the number and scale of rainfall, flood had already become so exceptional that caused major landslides in Hiroshima prefecture. In order to reduce the damage from such disasters, It is necessary to accurately grasp the characteristics of rainfall phenomenon, typhoons and torrential rains immediately. Understanding whether the meteorological phenomena change in short time will help finding the time constant of the turbulent component of rainfall time series to evaluate the uncertainty runoff discharge. Thus, an illustration the intensity and duration of rain events is critical to indicate the rainfall properties. This study analyses one minute rainrate by using the data from high rain-gauge of XRAIN and the work also caried out the research about characteristics of the periodic fluctuation.

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 Numerical calculations of climate change and weather forecast has been widely carried out, and Monin-Obukhov length based vertical distribution of wind velocity (Log+Linear law) is used in the calculations typically. However, it is not suitable for the numerical calculations because the stability scale of Monin-Obukhov is an algebraic expression. Also, it is very difficult to give a physical interpretation that the scale of the mixing length is negative when the atmosphere is instable. In addition, the scale on the vertical direction of the mixed layer should be set a priori when the atmosphere is instable. In order to solve these problems, a new differential equation of physically rigorous mixing length with considering atmospheric stability has been proposed in this study. The precision of wind velocity distribution in the vertical direction was confirmed by both observed data and Monin-Obukhov length bese Log+Linear law in the study. The proposed stability length can be used more conveniently than existing Monin-Obukhov length based mixing length to deal with the boundary layer in atmospheric calculations such as GCM or weather models.

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 The weather condition in the middle latitudes is controlled by westerly wind and high and low pressures, and these phenomena are interpreted as the baroclinic instability waves. A rotating fluid experiment by Fultz and Hide are known as the typical laboratory experiments of baroclinic instability waves. In this study, we introduced a new equipment having the unique feature characterized by the heated and cooled bottom. By this condition, 4-6 zonal wave numbers were observed and flow field were dynamically changed with time. At the same time, it was observed that the vorticity on center changed with baroclinic waves with time.

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 The purpose of this study is to prepare basic snow distribution data to areas along the Sea of Japan. It is useful in estimation future snow distribution due to climate change. As study targets, we try to verify relationship between surface sea temperature (SST) and snow depth distribution. And, we obtained local snow condition to characterized ion composition change. These examination induced influence degree of Japanese seawater. These results are as follows; (1) Japan sea side area include basins effected by SST and cold air mass of continental origin, and the quantity of snow changes due to it. (2) As usual snow condition, the snow distribution of the seawater origin depends on the river topography condition base on CL^-/NA⁺ ratio analysis. (3) A local characteristic snow process exists in much snow areas distance left from the coast.

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 In this paper, the authors focused on the tropical night for 24 years in 12 spots of Japan. We defined the tropical night as 13 hours from 6pm to the next 6am. And we compared the daily minimum temperature(instantaneous) with the minimum temperature(hourly mean value) in the tropical night. And we research on the time of the minimum temperature in the tropical night.
 As a result, we found that the most interrelated the minimum temperature in the tropical night is the almost equal to the next daily mean temperature, and time of the minimum temperature is from 4am to 6am in a day.

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 In this study, an evapotranspiration model that can express the amount of evapotranspiration accounting for differences in soil moisture and permeation characteristics of individual land-surface features is proposed. The model is composed of two components; the pervious area model based on SMPT model to represent the permeation process of the surface soil, and the impervious area model considering depression storage in impervious areas. Furthermore, the pervious area model takes into account the state of the soil moisture and differences in land use of the land-surface features, and estimates the latent and sensible heat using a heat balance equation based on the bulk formula. The model was applied to the highly urbanized upper Kanda River watershed, and the impacts of differences in land use on the spatial distribution of evapotranspiration and land-surface temperature was analyzed.

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 Himawari-8, the next-generation geostationary meteorological satellite, has launched successfully. Highly improved sensor AHI (Advanced Himawari Imager) loaded on the satellite has 16 observation bands (3 for visible, 3 for near-infrared and 10 for infrared), 2.5 minutes observation interval for the whole area of Japan and better spatial resolution than that of former sensor system. Some of observation bands are similar with the ones of Landsat/TM. Therefore, it is possible to compare the earth surface temperature and land-cover processed by Himawari-8 and Landsat.
 This study deals with the quality of Himawari-8/AHI by comparing with the Landsat-7/ETM+ as an example of Tokyo metropolitan area and discussed the availability to apply for the urban thermal environmental monitoring. Focusing on the diurnal temperature variation, the authors confirmed that the heat effect is remarkable in the manufactured land surface can be classified by AHI visible and near infra-red data. As a result, it is found that the Himawari-8/AHI demonstrates the expected performance and possible to apply to the thermal environmental monitoring for the urban.

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 This study, using 15 years of panel data of 41 municipalities in Hyogo, was conducted to assess a pricing system for household waste disposal service in Hyogo, which is expected to contribute to waste reduction and to improve social welfare. The findings obtained from this study are presented below. 1) Increased price of bags per kilogram of waste reduces combustible waste per capita by 0.076%. 2) In all 18 municipalities that have introduced pricing systems for waste, the difference in social surplus before and after system introduction a positive value of 14.49-81.97 million yen. 3) In all 18 municipalities, the change in social surplus in present prices is greater than that by optimal pricing.

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 We design a model to examine the determinants of the participation and continuation in river preservation activity by using structural equation modeling with questionnaire data from residents who participate in river preservation activities. The proposed model demonstrates that attachment to the local community and rivers, cost benefit evaluation have influence of the same degree as a determinant of participation and that cost benefit evaluation has strong influence more than attachment to the local community and rivers about a determinant of a continuation intention. Furthermore, multiple group analysis in the structural equation modeling showed that cost benefit evaluation has stronger influence for continuation intention in the person who belongs to Adopt-Program participation group more than the person who doesn't belong.

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 We design a model to examine the role of the pro-environmental activities by the university (lecture of environment at the university, environment measure by the university organization, environment measure by an environment club of the university) to enhance the pro-environmental behavior of university students (purchase of eco-friendly goods, avoid the purchase of unnecessary goods, power-saving behavior). The validity of the model is verified by structural equation modeling (SEM), using the questionnaire data of university students at two universities (the university of shiga prefecture, hiroshima shudo university). The proposed model demonstrates that lecture of environment at the university enhance the pro-environmental behavior of university students indirectly. Furthermore, multiple group analysis in the structural equation modeling showed that environment measure by an environment club of the university of shiga prefecture has given a strong influence on pro-environmental behavior of students compared with environment measure by an environment club of hiroshima shudo university.

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 Field tests of demand response (DR) power model, the policy controlling electric power demand using flexibility change power rates, are being conducted in many cities as the solution of tight energy supply-demand balance and installation into distributed energy system. This study aims to discuss of the relation of power rates and residential behavior with questionnaires, and to estimate energy consumption change on summer with time schedule model targeting the Nagoya metropolitan area (within 20km of CBD). The results indicate that 1) high power rates promote residential going out, 2) DR promote not only residential energy saving behavior in the short-term, but also replacement to high energy efficiency facilities in the long-term, 3) the mainly effects of DR are reduction of energy consumption in peak time, 4) in inner city where many singles live, the effects of DR may be smaller than the result of field tests.

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 In this study, we constructed a simulation model to simulate for future water demand by different sectors (agriculture, industry, and domestic) in each prefecture of Japan. We also estimated the future water resource of each prefecture based on the data of AMeDAS, the GCM (Global Climate Model), and statistical literatures. The water demand model was constructed by using published statistical data and information derived from the geographical information system (GIS). The model can estimate water demand by different sectors from year 2000 to 2050 (the simulation time step is 5 years) for different socioeconomic scenarios and with the introduction of water-saving technologies. The water demand for different scenarios is estimated by considering changes in population, economic situation, area of cultivated land, population with access to a water supply, water recycling in industrial processes, among other factors. We finally evaluated the gap between the water demand and supply by each prefecture. An understanding of future water demand and supply using this model could help in a re-evaluation of appropriate water use, thus avoiding water shortages as well as allowing for an examination of the influence on river flows.

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 Steel productions from 2012-2050 in Japan were estimated under various global assumptions based on combination n of scenarios such as goods trade scenarios and process selection scenarios. Process selection scenarios decide volume of steel production by process with considering steel consumption projection, supply-demand balance of steel, and scrap surplus. The range of steel production by process was analyzed.
 Maximum steel production was estimated under the scenario which consumes scrap in domestic steel production at maximum level. In 2035, steel production reaches 149 million ton because of increase in electric furnace steel. It, however, decreases towards 2050 and amounts to 120 million ton. Minimum steel production is under the scenario which assumes technology progress in steel making and supply-demand balance consideration in each region. Steel production decreases from base year and is 44 million ton in 2050.

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 This paper focused on the roof sprinkling system which prevents damage caused by roof snow. This system can prevent the snow accumulate by sprinkling water before the snow piled up on the surface of roof. By elucidating how sprinkling water temperature decreased, finding the optimal sprinkling condition, we aim to make the roof sprinkling system practical.
 From the experimental results, when sprinkling water, we found that there is a strong linear relationship between the roof surface temperature and the sprinkling water temperature. So by adjusting the springkling water temperature, it is considered that the roof surface temperature can be controlled. Also, in the process of sprinkling water, by considering the heat loss, using formulas which is generally used in heat transfer engineering, we calculated the decrease of sprinkling water temperature. Furthermore, the formulas of the heat loss also considers the physical condition of the roof. So they are not only fitable for experimental facility. They can be also applied to the actual roof.

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