This study approaches are to obtain regional snow information relathionship between chemical composition and short period snow fall event for future environmental problem(climate change, environmental load and so on). We set temperate zone heavy snow area(Fukushima prefecture) as study area. This study results((1)-(3)) is as fellow. (1) An ion and an element are high contain rate of non sea salt concentration in amphitheater and urban area as first snow period. (2) In case of low total ion concentration, non sea salt concentration is high depend on regional condition. (3) Snow fall ions make a transformation regional geographical condition(water area, amphitheater, obstructed geographical condition area.).

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 This paper proposes consumption-based CO₂ emission as an indicator of environmental load at a regional level. The followings are analyzed for Shiga prefecture (8 regions) ; 1) estimate production-based CO₂ emissions and consumption-based CO₂ emissions, 2) carbon leakage induced by CO₂ emission reduction, and 3) analyze structure of CO₂ emission by using CO₂ independent index(=production-based CO₂ emission / consumption-based CO₂ emission).
 In Shiga prefecture, CO₂ independent index in 2040 is 1.20. Among regions, the independent indexes are more than 1 in 4 out of 8 regions. It was checked that reductions of production-based CO₂ emissions would not induce carbon leakage by comparing the reduction rate of production-based and consumption-based CO₂ emissions. The contribution of non-metallic minerals sector to the independent index is remarkably large. So, it turns out that there is a possibility that the shrinkage of the sector may cause the large decrease of the independent index.

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 Changes in the occurrence of severe weather and clear days in the Yaeyama Islands under global warming conditions are assessed to estimate the impact of climate change on tourism. Although previous studies have investigated the impact of climate change on tourism using historical weather datasets and/or field surveys and have indicated a significant relationship between them, the investigation using future projection has not yet been studied comprehensively. In this study, the projection is thus conducted using, Database for Policy Decision making for Future climate change (d4PDF), a dataset generated by superensemble climate simulations. In order to use the dataset effectively, a simple method that considers the spread of the projected ensemble members is applied. This method estimates future changes and provide a range of uncertainty derived from the ensemble spread. The results indicate that the occurrence of severe events such as heavy precipitation or strong winds will decrease in summer, and the occurrence of clear days, which tourists prefer, will increase in winter. This suggests that climate change will induce regional weather changes which is supposed to be closely related with the satisfaction level of tourism in the Yaeyama Islands. Also, the approach proposed in this study has a potential to provide an efficient way to utilize massive climate projection datasets for various climate change impact assessment studies.

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 The advantages of using a large ensemble dataset is not only to evaluate occurrence probability of period and basin averaged rainfall but also to evaluate spatiotemporal characteristics of heavy rainfall from several thousands years rainfall data. In this study, we analyzed spatiotemporal distribution of annual maximum rainfall over Tokachi river basin in Hokkaido, Japan under historical and warmer climate condition from a large-ensemble dataset. The results showed that spatiotemporal distribution of annual maximum heavy rainfall under warmer climate condition is more concentrated. Because the concentration of rainfall causes increase of peak discharge and change of characteristics of flood damage, this change of rainfall characteristics included increase of rainfall amount must be considered for flood disaster prevention plan.

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 Land atmosphere interaction is a one of the important factor for Atmospheric Boundary Layer (ABL) processes, including cloud and precipitation formation. The present works thus aim to estimate the amount of soil moisture in idealized simulation affecting the shallow cumulus convection. Homogeneous soil moisture and horizontally homogeneous atmosphere is adapted. Potential of precipitation to occur on wetter or drier soil is quantified by running the model. Large Eddy Simulation (LES) with fully coupled to land surface and radiation model is used with different initial soil moisture percentage. Shallow cumulus cloud and rain shows different response under variety of soil moisture and wind conditions. Our study has showed that heat flux is influenced by soil moisture and wind condition. Decrease of soil moisture corresponds to decrease of net radiation and less difference of the maximum and minimum value of net radiation in diurnal cycle. It is also found that timing of convection does not vary significantly between the soil moisture availability of 100% - 60%, then it is gradually delayed for drier soil condition. Based on the study, it is concluded that cloud and rain formation process is influenced by the soil moisture and wind condition.

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 We conducted an internet questionnaire survey to clarify the characteristics and grasp the volume of the target of information provision for considering the communication policy and strategy to promote understanding and coping behavior of climate change risk. The analysis showed that the cluster with little interest in climate change, less knowledge, and unclear opinions accounted for more than 40% of all respondents, the cluster with high risk perception and enxiety about climate change and positive attitude toward mitigation and adaptation measures, and the cluster that is skeptical about climate change and do not recognize the necessity of any measures. We thought that the information providing approach to the cluster indifferent to climate change witch is the maximum volume was important. Then we discussed the content of information to promote understanding and countermeasures against climate change. By approaching with appropriate information and communication activities to each cluster with different thoughts and attitudes about climate change, it can be expected that deepening of understanding and positive evaluation and cooperation for mitigation/adaptation measures of climate change.

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 Anthropogenic climate change in this century will cause the increase in frequency and intensity of extremely hot day and, as a result, heat stress mortality is also expected to increase. This study analyses the economic damage caused by change in heat stress mortality under climate change considering uncertatinty in future climate and socio-economic change. As a result, the global economic damage caused by heat stress mortality relative to GDP would be limated to below 1% under RCP2.6 emission scenario assuming progress in GHGs mitigation. On the other hand, under RCP8.5 scenario, which is the most warming case, the global economic damage by the end of the century will be above 2% of GDP. While the primary factor of the economic damage increase in the developed regions is the heat stress mortality increase caused by the expected temperature increase, the VSL increase according to the expected economic growth will also contribute to the economic damage increase in the present developing countries.

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 Influences of transboundary air pollution and neighboring urban area sources are important for the environmental measures of PM_2.5. Research on PM_2.5 for Shiga Prefecture has been insufficient so far. Shiga prefecture has the various geographical features, for example, Lake Biwa, the basin and the mountains, and there are different characteristics from the Metropolitan area and remote isaland. In this study, PM_2.5 was observed at the northern and sourthern parts of Shiga prefecture and in Iga city in Mie prefecture separated from Shiga prefecture by mountains. Analyses of PM_2.5 concentration were carried out using the atmospheric chemistry transport model WRF/CMAQ. Good agreements between the WRF/CMAQ and the observation were obtained. In the winter season, transboundary air pollution caused similar daily variations of PM_2.5 concentration in the southern and northern parts of Shiga. In the summer season, the PM_2.5 concentrations increased in the sourthern part of Shiga prefecture and Iga city. These increases were due to the transport of air pollutants from the Kinki urban area.

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 The storage function (SF) models have been extensively used for the rainfall-runoff modeling in which the Kimura's model with lag time is widely used as a fundamental flow model, especially in Japan, due to its simple model structure. In this study, therefore, we aim to analyze the effect of lag time in the conventional Kimura's SF model on hydrograph reproducibility and compared with Prasad's SF model for an urban watershed in terms of error functions, storage hysteresis loop, and Akaike information criterion (AIC) perspective. The analysis of the effect of lag time on hydrograph reproducibility revealed that the use of optimum lag time in Kimura's model can greatly improve the performance. Further, the Kimura's SF model with optimum lag time exhibited higher hydrograph reproducibility associated with lowest error evaluation criteria and lowest AIC values in the single-peak events which makes it the superior model for single-peak events. Concurrently, Prasad's model depicted better performance in terms of reproducibility and AIC aspect during the multi-peak events, which indicates that it is the parsimonious model for multi-peak events.

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 Recently, as worldwide pandemic of dengue fever, researchers have attempted to predict the distribution of dengue vector mosquitoes. However, the earlier studies remained challenges in precisely understanding local prevalence of the vector mosquitos and its association with ambient environmental attributes. Here this study explored spatial and temporal oviposition patterns of the dengue vector mosquitos under heterogeneous meteorological, flooding, and land cover conditions using highly frequent data on the abundance of the dengue mosquito eggs observed throughout Metropolitan Manila. The abundance of the vector mosquito eggs (OI) tended to increase in the rainy season compared to the dry season. Spatial autocorrelation in the OI displayed a different trend depending on the seasons, suggesting that the spatial pattern of the oviposition of the vector mosquitoes are constrained by seasonally heterogeneous environmental conditions. The OI increased in response to increases in rainfall but in limited cases. In the residential area, the OI was higher than other land cover classifications.

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 We analyzed the relation between groundwater nitrate concentration and land use in the Miyakonojo basin. Nitrate concentration was measured in 1,202 wall in February and August from 2007 and 2016. Land use was based on 100m mesh data of National Land Numerical Information in FY 2009 and 2014, and was the ratio of land use type included within a certain distance from the observation point of nitrate concentration. As land use type, we picked up nine items such as rice field, other agricultural land, forest, wasteland, building land, road, railroad, other land and river and lake. As a result, we clarified the tendency of land use type at high and low nitrate concentrations. In addition, we also clarified the land use type that is highly correlated with nitrate concentration. At this time, we examined how to change the correlation coefficient with the ratio of land use type according to the distance from the observation point of nitrate concentration.

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 Due to that volcanic ash soils are distributed all over Japan, chemical evolution processes of water in these soils is important for evaluating groundwater pollution caused by agricultural activities. In this study, three kinds of volcanic ash soils were used for column experiments with leaching of KCl solution. As a result, we characterized reactive transport characteristics in volcanic ash soils. Relationship between ionic strength of soil solution and ion exchange capacities was determined. We also confirmed that selective coefficients of potassium and calcium depend on the ionic strength of soil water.

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 Estimation of the total phosphorus concentration distribution using satellite images on the Mekong River flood-plain was carried out. Partial least squares regression analysis was applied to satellite images of rainy season and dry season, and chlorophyll a concentration was obtained. Past studies about for relational expression between chlorophyll a and total phosphorus were examined, and the total phosphorus concentration was also determined from the concentration of chlorophyll a. From the regression equation in the rainy season the concentration distributions in the rainy season and the dry season were estimated. from the regression equation in the dry season, the concentration distributions in the rainy season and dry season were estimated. The correlation coefficient between the estimated value of the rainy season and the observation value by the regression equation of the rainy season was 0.97, and the correlation coefficient in the dry season was 0.070. The correlation coefficient in the dry season by the regression equation of the dry season was 0.66, whereas the correlation coefficient in the rainy season was -0.49. It is understood that the regression equation can not be applied to different seasons and it was found that it is necessary to obtain a regression equation on suitable season for more accurate estimation.

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 Reservoirs are generally closed water area, and largely impacted by inflowing rivers. Sediment in the Ogouchi reservoir has been known to be discharged from soils in catchment area via rainfall. It could be expected that prevention of discharge of manganese and phosphorous in soils would contribute to less manganese concentration in sediment and algal bloom prevention in the reservoir. This study focused on soil components in the reservoir catchment area. Amount of manganese and total phosphorous in soils were measured, and parameters were estimated for those two components by multiple regression analysis. Further, those two components were provided for correlation analysis with vegetations or slope in the catchments. It was found that there is a strong correlation between the amount of total phosphorous in soils and area ratio of a broadleaf tree.

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 In this article, we calculated the daily mean water temperature in a shallow lake by the optimal interpolation which is one of the data assimilation methods. We set three kinds of the weight of optimal interpolation to investigate an accuracy of calculation. As a result, the accuracy became quickly worse within 8 days of interplorating interval. In addition, when the interval of 8 days was longer, it was found that 30 to 50% of results by data assimilation was worse than results of heat budget method because results of both no data assimilation and by data assimilation were almost the same within 8 days.

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 The enterprise of Rice field dam is to install unique drainage devices in the rice fields. It is expected to mitigate peak flow rate from rice fields and to delay it. There are many types of drainage devices. It is nessesary to select a suitable devices for each region. Therefore, the purpose of this paper is to clarify storage function for each devices. We investigated water strage functions by comparison of three drainage devices, a free drainage, a box drainage vertically installed runoff control boards and a standard drainage, by hydraulics experiments and hydraulics simulations of falling water. A free drainage and a box drainage vertically installed runoff control boards are supposed to has a strage function so that they mitigate flood in the rice fields, but a standard drainage is supposed to has no storage function so that it does not mitigate it.
 As results, a box drainage vertically installed runoff control boards constantly works as a storage function and a free drainage works so only under the condition of high water depth and wide rice field area. Especially, a box drainage vertically installed runoff control boards decreases by 74% of peak flow rate and delay it for 280 minutes and a free drainage decreases by 44% of peak flow and delay it for 70 minutes under the conditions: total rainfall of 141 mm during one hours, central peaked type and rice field area of 2000m².

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 Three closely located lakes, namely Teganuma, Inbanuma and Kasumigaura, are located in Tonegawa basin, and their water qualities are influenced by similar weather condition.By analyzing the fluctuations of daily, monthly, and annual average water quality of these lakes, similarity is found by similar weather condition and individuality is found by characteristics of each lake. Daily COD of lake Teganuma raises by sunshine and rainfall, and decreases after rainfall.Daily COD of Kasumigaura raises by strong winds. Monthly COD of Teganuma and Kasumigaura raise in spring, and that of Innbanuma raises in summer. Fluctuations of annual average COD of 3 lakes are influenced by annual sunshine and annual rainfall.

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 Dam reservoirs are well known to greatly alter the downstream environments. However, few studies have explored effects of dam-induced flow alterations on stream ecosystems to date. Here this study investigated a river that harbors multiple hydropower dams to understand the impacts of hydrologic alteration on stream organisms (fishes, invertebrates, algae). We computed the Indicators of Hydrologic Alteration using the dam outflow discharge data and performed the principal component analysis. As a result, the first principal component was explained by extent of discharge and variation in flow regime (= 56.2%), and clearly distinguished the studied sites in the fully regulated river sections from the moderately regulated site. The first principal component displayed significant (P < 0.05) negative correlation with the fish individual number (r = -0.502), and positive correlation with the fish species diversity (r = 0.706). Hence, it is suggested that the partial riverine organisms may be affected by different extent of flow alteration by the hydropower dams.

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 This study aims to reveal the optimal spatial resolution of rainfall that is necessary for flood analysis using General Circulation Models (GCMs) and Regional Climate Models (RCMs) in climate change impact assessment study in local scale.Therefore, we made an attempt to evaluate the impact of different spatial resolution of rainfall on runoff analysis by using a distributed hydrological model and dynamical downscaling (DDS) experiments on selected past flood events. As the result, it is found that rainfall distribution and runoff analysis are different between JRA-55 20km, 5km, 2km and 1km DDS experiments. Furthermore, it is confirmed that peak discharge in runoff analysis is not affected by aggregated rainfall distribution based on JRA-55 1km DDS experiments relative to runoff analysis with DDS experiments.

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 Himawari-8, the next-generation geostationary meteorological satellite, was launched on 7 October 2014, and began operation on 7 July 2015. 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 far infrared), 2.5 minutes observation interval for the whole area of Japan and better spatial resolution than that of former Himawari-6 and -7 sensor systems. Some of observation bands are similar with the ones of Landsat/TM. Therefore, it is possible to observe the land-cover condition by visible and near infra-red data and the Earth surface temperature by thermal infrared data.
 This study visualizes and quantifies the heat island phenomenon by evaluating the daily variation in urban area thermal environments. Himawari-8 data are analyzed using surface trend analysis from a macroscopic point of view. Statistical values such as population and power consumption, which cause the heat island phenomenon, tend to be related to increased temperatures at noon, as well as to the remaining increased temperature in the evening. It is difficult to explain the phenomenon using only statistical values of human activities because it is also influenced by a city's location (latitude) and the surrounding land cover situation.

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 This paper evaluated the global impats of sea level rise and astronomical high tides using 8 GCM (CMIP5, RCP scenarios) and socioeconomic scenarios (SSP scenarios). As a result, the potential inundated area in 2100 was estimated between 350 thousand km² (NorESM1-M) and 460 thousand km² (MIROC-ESM-CHEM) under RCP8.5. The difference was 29% from the average value. The affected population in 2100 varied from 57 million (NorESM1-M, SSP1) to 117 million (MIROC-ESM-CHEM, SSP3) under RCP 8.5 while it varied from 43 million (IPSL-CM5A-LR, SSP1) to 96 million (MIROC-ESM-CHEM, SSP3) under RCP2.6. The economic damage varied from 164 billion dollars (GFDL-ESM2M, SSP3) to 526 billion dollars (MIROC-ESM-CHEM, SSP1) under RCP8.5 while it varied from 147 billion dollars (NorESM1-M, SSP3) to 452 billion dollars (MIROC-ESM-CHEM, SSP1) under RCP2.6.

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 It is concerned that sea-level rise due to global warming affects to the various phenomena in Fongafale Island of Funafuti Atoll, Tuvalu. Especially the overtopping waves, inundation and cultivation of Taro will be influenced strongly because these items involve to the sea surface height. This study estimated the influence against these items that are overtopping waves, inundation and cultivation of Taro. The results on nearshore wave height simulation indicated that the sea-level rise cause increase of wave height in both lagoonal and oceanic coasts. In the ocean-side coast, the increasing rate was over 200% partly. Additionally, calculated potential area of Inundation caused by extreme high tide will be increase by the sea-level rise of 10cm. Potential region of suitable for Taro-pit will be decrease by sea-level rise and the present Taro-pit will change to the unsuitable as cultivate region.

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 In Japan, some deaths were reported at an inert solid waste landfill site after exposure to hydrogen sulfide (H₂S) generated at the site. H₂S gas is produced when sulfate-reducing bacteria convert sulfate derived from waste gypsum board under anaerobic conditions. The recommended countermeasure is to supply oxygen by installing gas venting pipes. However, a large cost is necessary for pipe installation and the pipes are not applicable to coastal landfill sites. On the other hand, H₂S generation suppression by nitrate (NO₃) addition has been reported in sewage systems. In this study, in order to develop a method to suppress H₂S generation at a landfill site, the extent of H₂S suppression and organic carbon reduction by NO₃ or gaseous oxygen addition were quantitatively estimated. H₂S generation ratio was decreased to below 0.1 and organic carbon reduction rate was increased by NO₃ reagent or gaseous oxygen addition. However, NO₃ extracted from compost had no suppression nor organic carbon reduction effect.

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 With regard to an index in relation to organic carbon content in order to suppress high concentration hydrogen sulfide generation at solid waste landfill site, it is necessary to estimate an effectiveness of an index concidering utilization rate of organic carbon, rather than total organic carbon (TOC) which doesn't distinguish easily decomposable and refractory organic carbon. In this study, potential of hydrogen sulfide generation with extraction liquid from wood, i.e., cellulosic organic carbon was measured and compaired with the potential with easily decomposable organic carbon (microorganism culture medium) which was obtained by previous study. The potential with extraction liquid from wood was smaller than that with microorganism culture medium at same TOC. If the standard for suppression of high concentration hydrogen sulfide generation was established by TOC, wood had to be removed excessively from a solid waste. High concentration hydrogen sulfide was not generated from extraction liquid from wood and microorganism culture medium at less than 0.3 mmol-O₂ / (L·h) of oxygen consumption rate.

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 In order to support planning of disaster waste disposal, a numerical model simulating disaster waste transportation and disposal was developed. The proposed model tracks the movement of disaster waste between originating region, temporary storage areas and final disposal site. A crushing/classification process at temporary storage areas, Number of vehicle as a carrier, transit route, a capacity of temporary storage areas and final disposal site are freely settable in the model. The model was applied for a city in Mie prefecture aiming at evaluating of actual disaster waste disposal plan at the time of the occurrence of Nankai Trough earthquake. The result of simulation indicated that a number of crushing/classification equipment and workers were required in order to execute disaster waste disposal.

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 It is necessary to improve suitable the environmental conditions in the sea for coral habitats in order to encourage conservation and rehabilitation of the coral reef ecosystem in crisis of Yaeyama islands. Therefore, the application of the local environmental certification to encourage improvement of business activities such as agriculture, fishery, and tourism industry to reduce the impacts for coral reef ecosystems has been focused. As a part of this purpose, the amount of the load of the nutrient salt as nitrogen and phosphorus from each various stakeholder on the land are analyzed and evaluated quantitatively in this paper. Then, in order to examine the possibility to apply the local environmental certification to the pineapple cultivation, the estimation is conducted with considering three levels of load reduction by local environmental certification of pineapple cultivation which is one of main sources of nutrient salt. As a result, it was found that nutrient salts can be reduced by increasing the number of farmers such as eco farmers and special cultivated agricultural products in Okinawa Prefecture.

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 This study estimates total power generation and its component, and greenhouse gas (GHG) abatement cost for Japanese 2050's 80% GHG emissions reduction target. An economic model (General equilibrium model) is used for the estimation and energy technological model results are reflected in the energy representation in the economic model so that the energy flow outcomes can be more realistic than the outcomes of general economic model which typically uses abstract function. As results, GDP losses associated with the GHG emissions reduction in 2050 is 0.4% which is around 2% lower than conventional economic model approach. The emissions reduction potential in the energy technological model could be different from that of original in the economic model, which consequently changes production and household activities and carbon tax revenues.

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 HYPE(hydrological predictions for the environment) model was applied for Kinokawa river basin in order to evaluate an applicability of HYPE for Japanese watershed. Firstly, a fundamental HYPE in Kinokawa was constructed by using landuse, soil, topology information based on Swedish HYPE. Secondly, a calibration based on Markov Chain Monte Carlo method was performed in order to improve prediction accuracy of Kinokawa river flow rate. Then, point and non-point sources of nitrogen and phosphorus were implemented aming at runoff analysis. According to the comparison of simulated and observed nutrient load, it was shown that the accuracy of nutrient load predicted by HYPE was reasonable. In conclusion, it was suggested that HYPE was available for Japanese watershed aiming at water and nutrient runoff analysis.

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 It has been recognized that dynamics of water and the associated materials such as sediment and nutrients are important to conserve ecosystem existing in a watershed. Among others, excess soil and nutrients transports toward the coastal zones and deposition on corals are one of the major environmental problems in Okinawa, Japan, in which agricultural area is the major source of sediment yield. In this study, we focused on a soil erosion reduction measure by using biological ground cover by algae and fungi, called Biological Soil Crust, BSC. As the results of erosion experiments, interrill and rill erosion rate increased with increasing rainfall intensity and flow shear stress acting on the soil particles under the bare ground condition. These erosion rates decreased under the ground covered condition with BSC. Significantly, rill erosion did not occur while the soil is covered with BSC. The reduction effect of BSC was sustained even though the surface cover was detached by rain drops. Soil erodibities were identified from measured erosion rates, and the parameters of soil erodibilities were input into the Water Erosion Prediction Project, WEPP model. Simulation results of WEPP model revealed that the sediment yield under the ground covered condition with BSC decreased by around 90% of that under the bare ground condition.

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 This paper presents the reproducibility analysis of the distribution hydrological model using several rainfall data, such as XRAIN and ground observation rainfall data, applied to the upper basin of Kanda river in Tokyo. The highest reproducibility is observed by using high density deployed ground observation rainfall, among the simulation using other rainfall data including XRAIN with its spacial high resolution. From the simulation using XRAIN, direct use of XRAIN's spatial distribution data to the hydrological meshed model revealed higher reproducibility than the simulation using averaged XRAIN in the basin.

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 In August 2016, when typhoon 10^th approached Hokkaido, record heavy rainfall occurred near the Hidaka Mountain. In this research, we aimed to classify and discuss the heavy rain characteristics using the calculation of Brunt-Vaisala frequency to show the stability of the atmosphere and the dimensionless number. Brunt-Vaisala frequency in dry state and wet Brunt-Vaisala frequency including wetting effect respectively. In area with high altitudes, the Brunt-Vaisala frequency was calculated to be small irrespective of the dry and wet state, suggesting that the atmosphere is unstable. We classified the heavy rain according to the magnitude of the dimensionless number which is the ratio of the kinetic energy of the atmospheric flow around the mountain area and the energy necessary to cross the mountain. It was found that the rainfall increases with the altitude rose, especially in the case where the dimensionless number was large, resulting in more localized rainfall.

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 This study makes the simulation of a compound disaster involving flood and storm surge and evalu-ates the damage cost for the disaster in Japan. The tide level and daily rainfall, which cause the com-pound disasters, are calculated by means of frequency analysis for annual minimum atmospheric pres-sure. 2D non-uniform flow model expressing the inundation depth is carried out using the tide level data on coastline and daily rainfall distribution interpolated as input data. Damage cost is estimated using the inundation depth by each land use. The annual expected damage cost of flood in whole Japan is 1.1 tril-lion JPY, that of storm surge is 468 billion JPY, and that of compound disaster is 778 billion JPY. In 38 prefectures out of 46 prefectures of Japan, the damage cost of only flood is larger than that of only storm surge and the compound disasters.

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 The risks associated with changes in land use are a common concern, especially in relation to their potential impact on many cities around the world. Jakarta, Indonesia is a typical urbanized Asian city where flooding presents a challenge. In this study, our main objective was to evaluate quantitatively the impact of changes in the use of land upstream of the city by using a flood inundation model to analyze several land-use-change scenarios. We considered four scenarios of future changes in land use in Jakarta based on the SLEUTH model: the worst-case, compact-growth, and controlled-growth-I and -II scenarios. The controlled-growth is a scenario to decrease the growth rate and delay the progress of urbanization compared to the compact-growth scenario.
 According to our analyses, the predicted changes in land use with the land subsidence in the worst-case and controlled-growth-II scenarios would cause flood inundation volumes in 2050 to be 37% and 27% larger than in 2013, respectively. Thus, even under the controlled-growth-II scenario, the modeled changes in land use with the land subsidence would significantly increase flood inundation. Based on these results, we strongly recommend the Jakarta government to regulate land use in the forested upper regions and land subsidence in the lower regions as soon as possible to reduce future flood damage to the city.

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 Frequency-Damage (FD) method is a statistical analysis for evaluating flood risk curves based on long-term flood damage records. In this study, we propose an improvement of existing FD method that can take account of the years without any disaster damage in a small municipality. By applying existing FD and improved FD method to Japanese municipalities, we were able to show two distinct advantages of the improved FD method. First, improved FD method decreases over and under estimation of the expected value of flood risk compared with the annual average flood damage loss. Second, it reflects more accurately the probabilistic characteristics of flood risk. Therefore, it expands applicability from regional to smaller domains up to basic municipalities. This new method can be used for investigating the regional differences of flood risks and the flood risk characteristics of municipalities.

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 An integrated flood risk management (FRM) plan was established in the Philippines for the first time in 2012 after the disastrous flooding brought by Typhoon Ondoy in 2009. It is a crucial task to identify and analyze the barriers that may hamper the effective implementation of the FRM plan. In this study, barriers to FRM were identified from a collection of literature related to flooding then interrelationships among barriers were analyzed by conducting a pairwise assessment by experts. Barriers to FRM in Metro Manila are found to be related to three aspects namely, governance, social and scientific resources aspects. There are 4, 3 and 5 barriers identified in the governance, social and scientific resources aspect, respectively. The barrier interrelationships were elicited by 5 carefully selected local experts and practitioners in the Philippines. The results of this study show that barriers in the governance aspect heavily influence all other barriers while the barriers on the social aspect have the least influence but strongly depends on the other aspects. The collective perception of the 5 local experts and practitioners also showed satisfactory understanding on the barriers in FRM. This study was able to identify and analyze the interrelationship of each FRM barriers which can provide insights to decision makers on how to overcome them.

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 Statistical estimation of present hydrological frequency analysis has significant uncertainty caused by the shortage of extreme hydrological data. We proposed a new theoretical framework of hydrological frequency analysis including confidence interval based on probability limit method test. By using this confidence interval, reliable statistical estimation can be possible under limited extreme hydrological data and we can evaluate hydrological phenonmenon which was considered unexpected conventionaly with reasonable return period. In this research, runoff analysis is performed at Kusaki dam basin by using rainfall time intensity extended to confidence limit value of probable total rainfall as input. Through this runoff analysis, the fluctuation characteristics of probable flood peak discharge is shown. Also, the relationship between shape of probable rainfall intensity and probable flood peak discharge is clarified.

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 Hydropower generation has a large introduction cost compared with other renewable energy, but stable power supply can be expected. Since hydropower generation facilities are generally located in mountain forest areas, the introduction in forestry area is also assumed. In recent years, however, there are forestry areas where devastation is progressing due to sluggish wood cost and aging of forestry workers. In this study, we assumed the introduction of hydropower in the forestry area and analyzed the influence of forest phase change by forestry operating system on the flow regime, and evaluated the influence on generated electric energy and unit price of electricity generation. In addition to a slight increase in the amount of electricity generated by the forestry management scenario which carries out aggressive afforestation and logging, the forest road will be appropriately developed, which is considered to be indirectly useful for maintenance of hydropower generation facilities.

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 Hydropower(HP) is the major source of renewable energy supply in Nepal. The current power generation is only 1% of the gross theoretical hydropower potential (84,000 MW). In this research, we tried to quantify the potential locations for hydropower plant (HPP) sites within Bagmati River Basin and estimate the total energy that can be generated spatially. We used SWAT hydrological model for discharge simulation and GIS for spotting potential locations. Then, general power equation was used to calculate the total power that can be generated from the basin area. Potential sites having head difference of more than 10m was included for estimation of the energy. Different criteria (for example, technical and socio-environmental constraints) were setup for locating the potential sites. Flow duration curve (FDC) for each HPP sites were determined at different flow exceedance of discharge for determining design discharge. First 80 potential sites were spotted after applying the technical constraints and finally 73 sites were determined as HP potential sites with gross head differences of 12m to 689m when applying the socio-environmental constraints. These potential sites were categorized as micro hydro, small hydro, medium hydro and mega hydro and numbers of HP sites were found to be 4, 25, 35 and 9 respectively at 40% of flow exceedance. The total energy that can be generated from the basin area were calculated by summing up all the energy that can be produced from individual potential site and calculated to be 3442.6 MW. The results of the research can be utilized by the policy makers and developers of the renewable energy for generating HP for sustainable development and green environment.

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 Human activity is the most significant factor driving water demand. In this paper, we quantify the water demand in the transboundary 3S River Basin (Sesan, Sekong and Srepok) according to projected societal and economic developments, the so-called Shared Socioeconomic Pathways (SSPs). We considered the water demand across four water use sectors, namely domestic, irrigation, industrial and environmental, and derived estimations that were compatible with the three SSPs (SSP1, SSP2 and SSP3) for three periods: the 2030s, 2060s and 2090s. Three population projections, corresponding to the three SSPs, were made using the cohort component and ratio methods. The Land Change Modeler (LCM) model was employed to prognosticate the future land use land cover change. By the end of this century, the basin's population is projected to increase by 60%, 117% and 139% under SSP1, SSP2, and SSP3 respectively. Agricultural and urban areas are predicted to increase by 33% and 100% in the 2090s, respectively. Consequently, total water demand would increase by 98%, 101.9% and 102.8%, under SSP1, SSP2, and SSP3 by the end of this century respectively. The results of this study will help policy makers and planners in developing appropriate water supply plans to tackle the continuous but uncertain increases in future demand.

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 The Nihonbashi River is a branch of the Kanda River which is classified as a Class A river managed by the Tokyo Metropolitan Government. The 1964 Tokyo Olympic Games was an opportunity to advance the construction of the Shutoko (Metropolitan) Expressway over the Nihonbashi River and the Nihonbashi Bridge. The Nihonbashi and Otemachi areas are currently undergoing redevelopment projects in preparation for the 2020 Tokyo Olympic Games.
 To redevelop and improve the Nihonbashi River environment, a section of the Shutoko Expressway is planned to be relocated underground. Integration with the large scale private developments in the National Strategic Special Zones is being sought, based on Special Urban Reconstruction Law.
 This paper investigates the design philosophy for river control concerning the plans for the Shutoko Expressway construction over the Nihonbashi River at the time of the 1964 Olympic Games. Furthermore, this paper provides an overview of the differences in the urban river environment policies between 1964 and the present time.

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 In recent years, it has become necessary for local governments to establish low-carbon societies through their initiatives. Thus, they have formulated long-term plans for energy systems. However, unexpected future risks cannot be considered in these plans. In this study, we developed a long-term energy planning model using a two-stage stochastic programming method that could be implemented by local governments. This model can estimate an optimal energy supply system while considering future uncertainties; for example, demand and the unit value of CO₂ for power companies.
 When this model was applied to the energy system planning of Toyama Prefecture for the period 2016 to 2050, it indicated a significant increase in hydropower and geothermal power generation, that has abundant presence in Toyama Prefecture, and a reduction in power supplied from the grid. For the final 5-year period (2046 to 2050) of this model, the amount of power supply predicted from grid energy was 45.6 %, geothermal power was 29.5 %, hydraulic power was 14.3 %, and energy from other sources was 10.6 %.

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 This study examines the statistical causal relationship between recent chronic decreasing of skiing visitors and global warming. Concretely speaking, paying attention to the number of skiing visitors in Nagano Prefectures from 2006 to 2017, candidates of explanatory variables are extracted by usual OLS with time series data sets of several ski areas. Subsequently, with pooling data for each prefecture, we engage in panel data analysis and decompose it into the factor of climate change and the others. As the results, the annual change rate of skiing visitors due to total factor, the one due to climate change, and the one due to other reasons are -2.95%, 0.46%, and -3.41% respectably for Nagano. These findings show that decreasing of skiing visitors in this term stemmed largely from social reasons other than climate change and that the weather rather mitigated slightly the decline.

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 This study demonstrated to evaluate potentials of CO₂ emission reduction by implementation of ground source heat pump systems for heating use in a standard residence over the land of Japan. In each 10-km grid of different climate and geologic conditions, required borehole heat exchaneger length for the sustainable system in terms of soil and brain temperatures were determined by the annual operation simulation based on the three-dimensional geo-property database. The potential CO₂ emission reduction of a residence and the total reduction in each grid were calculated, and were compared among 46 prefectures. As a result, the potential reduction of each residence was high in the cold regions and the mountaineous regions. On the other hand, the potential reduction in entire grid was high in the relatively warm areas, especially in the industrial and urbanized areas along the coarst of Pacific ocean, because the residence density was large. These results revealed the potentially high contributons of ground source heat pump systems for CO₂ emission reduction, not only in cold regions where the sytstems have been developed in advance, but also in warm regions, i.e., in any prefecture of Japan.

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 Introduction of power system stabilization measures such as demand response (DR) and battery is indispensable under the large-scale deployment of variable renewables. Although a power supply model specialized in the electric power sector is commonly used for power system analysis, with this model alone, it is impossible to estimate the amount of future potential of DR technologies and power demand under low-carbon target. In this research, we combined the information of the technology selection model called AIM/Enduse[Japan], that can consider the entire energy system, with the power supply model, and estimated the introduction amount of the power system stabilization measures under the long-term low carbon scenario. Allowance of annual CO₂ emissions from power sector, electricity demand for both DR and non-DR technologies, and generation capacities were adopted from AIM/Enduse [Japan] as input parameters for the power supply model. As a result, introduction of system stabilization measures such as batteries and DR could reduce power generation cost under low carbon scenario by about 1.6 trillion yen, and could increase the capacity factor of gas thermal power plants by 3.5 - 6.1%. In addition, the results showed that it was necessary to introduce battery for short-term fluctuation of the scale exceeding the current amount of pumped-storage power generation in 2040. Moreover, despite the improvement of capacity factor of gas thermal power plants by the combining multiple power system stabilization measures, the capacity factor of thermal power plants would decrease to 25% after 2035 due to the high share of variable renewables. Improvement of DR modeling, consideration of future technology uncertainties and impact on power distribution grids, and iterative calculation between AIM/Enduse[Japan] and the power supply model are future tasks.

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 The objective of this paper is to find useful implications for effective ways to increase the number of Transferable Development Rights which is expected to conserve farmlands and natural areas in the U.S. After examining the relevant ordinances and other official documents by the 5 municipalities in Pinelands, New Jersey and in North Kingstown, Rhode Island, we found several negative factors which might discourage TDR transactions as follows: 1) the limited number of municipalities which can deal with each other, 2) small-sclae receiving areas, 3) prohibition of residential use in a sending area which allows residential use before the TDR transaction, and 4) additional condiotons to receive bonus floors in a receiving area.

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 To simply analyze the characteristic of new water quality index, which shows the level of activity along the rivers, Instagram data was used. Firstly, we grasped the relevance between the index and the observed number of river users. Secondly, rank weight of new index was estimated from relevance obtained. Finally, relation between estimated new index and Instagram data was verified. As a result, new index was related to the number of people playing in the water and at the waterside. “Putting face in the river easily” was four or five times worth than “playing in the river easily”, “impossible to enter the river but possible to approach the river” and “approaching the river difficulty”. In relation between posts including a word such as “fishing” and the new index, if the fish like “bass”, which can live in the bad quality water, is caught, the new index is lower. On the other hand, it is necessary to pay attention to the relation the posted point and investigation spot of the new index.

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 Sea level rise due to climate change may threaten humans who live near the coastal areas. To adapt to climate change, it is important to examine the cost of coastal protection in the context of climate change. It can be protected more efficiently and economically whether planted mangrove forests or installed dikes along the toropical and subtropical coastline. However, few studies have been conducted to examine the long-term feasibility and impact of adaptation measures at a national level. This study carried out cost analysis of such measures in Philippines and Vietnam. It was found that combining mangrove forests and dikes were potentially effective in Vietnam where the extent of inundation and economic damage is expected to large in the future. Conversely, the feasibility of such measure in the Philippines was lower than Vietnam, requiring site-specific management solutions to accommodate local conditions.

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 This paper introduce an assessment method for climate change risk for local officials with their subjective evaluation to some elements necessary for planning climate change adaptation, and clarify their needs of climate science and technologies and perception gaps among departments of local governments by applying the method to some local governments. The main results demonstrate as follows; i) the higher needs for scientific data is on climate change impact on irrigated rice cultivation, fruit cultivation, heat attack, natural forest, and mudflow disaster for shorter term and specific areas. ii) with the assessment method, visualized information of gaps and common points of departments are provided, and this is expected to be used in examining adaptation within cross-departmental organisation.

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 Under the Great East Japan Earthquake, Mound type Tsunami Evacuation Facility is focused in the reason of the survivors by being evacuated to Mound type Facility from Tsunami. On the basis of examination results in Fukuroi-city, Shizuoka-prefecture, SEO et al.¹⁾ proposed the design method of Mound type Tsunami Evacuation Facility. This report examines the crest height of Mound type Tsunami Evacuation Facility in detail among the various examinations of the design method. Especially, crest height by the comparison between maximum inundation depth before the construction of Tsunami Evacuation Facility and maximum inundation depth in front of the Facility after the construction as the result of tsunami simulation shall be examined. In the case of the change of the flow field significantly, it is necessary that we analyze by the resolution to express the peripheral structures, houses of the like, et al.

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 In order to measure the economic impact of changes in environmental quality due to climate change in Japan, by using a computable general equilibrium model (CGE) that integrates a utility function that has an environmental quality factor as an independent variable derived from a recreation demand function in a travel cost method (TCM), we aim to estimate the damage cost of beach erosion in each prefecture and in Japan and to evaluate economic effectiveness of hypothetical adaptation measure to restore sandy beach. We use the future projections of beach erosion rates calculated by 2 periods (2031-2050 and 2081-2100), 3 RCPs (RCP2.6, RCP4.5 and RCP8.5) and 3 climate models (MIROC5, MRI-CGCM3 and HadGEM2-ES), respectively. Also, we assume the average adaptation cost per unit area to be 21,596 JPY per square meter. The main findings in our study are shown as follows. 1) In the RCP8.5, the damage costs of beach erosion were estimated to be from 17.4 million yen per year to 25.2 yen per year in 2031-2050 and from 61.5 million yen per year to 64.4 million yen per year in 2081-2100, respectively. 2) In all periods, all RCPs and all climate models, four prefectures that the cost benefit ratio exceeds 1.0 were Kanagawa, Osaka, Saga and Kumamoto.

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