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The small rain tendency had continued from summer to winter of 2005 in Northern Kyushu. As a result, year precipitation in 2005 was 1020mm (common year ratio 0.64) in Fukuoka City. This value is a little value in third on the observation history. Then, the artificial rainfall experiment which had used a liquid carbon (LC) on February 4, 2006 was done twice in east side of Iki island in Nagasaki Pref.
On Feb.4,the NNW wind chiefly blew on the ground because of the distribution of atmospheric pressure of the type in winter. The altitude of target cloud top was about 2100m, the cloud bottom altitude was about 1000m, and the thickness of the cloud was about 1000m. The scatter rate of LC was 10g/s,and the scatter time was 120seconds.
The maximum area of an artificial echo was 24km2,and the maximum echo top was about 3000m. Longevity was 120 minutes.
As for a very thin cloud,artificial is assumed to be impossible like this through it is natural to bringing precipitation. However, we succeeded in bringing precipitation from this very thin cloud.

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The authers are constructing a Disaster Information System for Debris flows. This system was recorded the precipition data at T0514 observered by MILT Japan via high speed Fiber line.It is examined this system is possible to predict the Debris flows at Tarumi city, Kagoshima Prefecture, Japan caused by T0514 with Heavy rainfall. The potential of the disaster is displayed by a map. It is reasonable result.

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The heat flux during the pre-monsoon period in the inland area of Thailand are investigated using wind and moisture fields and sensible and latent heat flux by the NCEP/NCAR reanalysis, and precipitation, sensible and latent heat flux observational data in 1998 and 2003. From the middle of March before the monsoon onset, the latent heat flux is dominant and the land condition is wet. Moreover, the intermittent dominance of the latent heat flux is analyzed from the middle of February. The composite analysis in the intermittent dominant of the latent heat flux in the middle of February shows that the dominant area of the latent heat flux covers over the south part of China, the inland area of Thailand and Cambodia. In the upper troposphere, the trough is analyzed. Additionally, the precipitable water increases centering on the inland area of Thailand. It is suggested that the intermittent dominance of the latent heat flux from land contributes to the moist condition of the atmosphere. On the other hand, the latent heat flux does not increase until the onset of summer monsoon over India and the center part of Myanmar. The property of the heat flux from land is not similar over the Asian monsoon area during the pre-monsoon period.

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Large aparture scintillometer was used to measure regional sensible heat flux over Mongolian grassland. The observation was made as a part of the field campaign during the intensive observation period of RAISE (aingelands Atmosphere-Hydrosphere Interaction Study Experiment in Northeastern Asia) project. The receiver of the scintillometer was placed at different place every day to measure the sensible heat flux from different land surface. It was found that the measurements of the scintillometer were comparable with the eddy covariance measurements. A detailed analysis suggest that the scintillometry capture the flux from various land covers with in its source area.

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In the irrigated crop fields and the salinized bare field of the Hetao Irrigation District in the Yellow River Basin, evapotranspiration was estimated by the Bowen ratio energy budget method based on the micrometeorological measurements. By applying the bulk equation of evapotranspiration, canopy resistance was parameterized by solar radiation and soil water content for each field to develop the mono-layer evapotranspiration model. This model was incorporated to the SPAC model to calculate daily evapotranspiration and vertical profiles of soil water content. The model could reproduce evapotranspiration in each field successfully. Finally, using the land use map, which was analyzed by the LADSAT image data, the spatial distribution of daily evapotranspiration in the Hetao Irrigation District was developed.

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The SiBUC (Simple Biosphere including Urban Canopy) land surface scheme,which has irrigation scheme, uses mosaic approach to incorporate allkind of land use into land surface scheme. The SiBUC model can calculateirrigation water requirement, which is amount of water that must beapplied to achieve optimal crop growth. The SiBUC model is one ofparticipants of the GSWP2 (the 2nd Global Soil Wetness Project). Usingthe SiBUC model, global 10-year simulation considering irrigation effecthas been implemented, and global distribution of hydrological variablesincluding irrigation water requirement has been estimated. To understandinter-annual variability of irrigation water requirement, two correlation coefficients are calculated; between irrigation water requirement and precipitation, between NDVI (Normalized Difference Vegetation Index) and precipitation. From the analysis of two correlation coefficients, it can be implied that differences of correlation expresses whether the irrigation facilities are adequate or not. Moreover, it can be pointed out where agricultural productivity is resistant to precipitation variability or is vulnerable to precipitation variability. Due to the analysis of both outputs from the land surface scheme and satellite remote sensing data set, the condition for stability of the agricultural productivity also can be implied.

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Based on hydrological and meteorological data analysis, landcover type and green-up onset and offset are estimated using time-series analysis of PAL (Pathfinder AVHRR Land) data from January 1982 to Decenber1 1998. Our results show that air temperature determines green-up time and soil moisture (which is related to precipitation, temperature, snow melting and discharge) determines the vegetation type and its response in this area. Some of detected landcover changing places during analysis period are caused by air temperature warming because it brings promoting of evapotranspiration and dry soil condition. However, most of changing places are caused by not only natural condition but human activity directly or indirectly. Water usage system in this area affects large scale hydrological cycle and vegetation types so much.

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We have developed the global basins database (GBDB). GBDB includes the drainage basins map which consists of polygons of catchments which are subdivisions of basins into elementary drainage areas. Each polygon of a basin is identified by a Pfafstetter code and is attributed with geographic, topographic, and social information. The drainage basins map were generated from digital elevation models of which natural depressions are manually identified and which are modified by the methods of "stream burning" and "ridge fencing". We used the stream data and the basin data modified by collected data, atlases, and basin maps in the procedures of "stream burning" and "ridge fencing". We had two comparisons to verify the accuracy of the drainage basins map of GBDB. We compared the drainage basins map of GBDB with collected basin data, and the calculated upstream areas with the reported ones at river discharge stations. The results of those comparisons reveals that GBDB provides a more accurate and reliable drainage basins map than HYDRO1k database.

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[in Japanese]

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Recent, in connection with change of natural environment or social environment, there is much record local heavy rainfall and floods have occurred frequently all over the country. The usual flood forecast system cannot predict a water level correctly.
This study will show a new countermeasure of the rainfall/flood forecasting method to the climate change. It assumes that the rainfall forecast error is dependent on the degree of the strength of rain (standard deviation of rain).The new flood forecasting measure is one of the flexible measures which prevent the high water level by too much prediction and the lower water level by too little prediction using the assumption.
In addition, it is necessary to direct one's attention also to series change (hyetograph) for the further improvement in accuracy.

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This study proposes a new hydrogeological model with distributed runoff properties to be physically based. The proposed model originates from the Hydro-BEAM quantitatively equivalent to actual runoffs in subsurface layers. The runoff model including water movement on a ground surface and in subsurface layers is also used in numerical simulations close to realistic behavior. It implicitly connects a conjunctive linkage between surface and ground water behavior through belief modeling for unsaturated flow. It can be proven that the developed model successfully evaluates three-dimensionally distributed water resources of surface, unsaturated and ground water linked with each other.

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The daily long-term runoff analysis is carried out for about 4 years between Jun 2002 and April 2006 for 5 Dam river basins in Hokkaido area and Tohoku area. The study basins are of Iwaonai Dam, Izarigawa Dam, Jyozankei Dam, Asase-ishikawa Dam and Tamagawa Dam. These basins are in the cold climate district and precipitation data in winter season is scarcely because of snowfall and freezing. The hydrological model presented by Ando et al. is used in this study. This model is improved for the use of GIS elevation data and the seasonal relationship of the precipitation – elevation is considered in this study. The GIS mesh size for the calculation of precipitation and snow depth and melt are 100 m. Only the rain-gauge station at Dam site is available for the winter season for each basin, and so the data is used to estimated for the basin precipitation. Regional parameters of the net storm rainfall - direct runoff relationship and the groundwater recession constant are investigated and used in the analysis. The results showed that the calculated hydrograph agree with the observed hydrograph.

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[in Japanese]

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Rice cropping patterns of Mekong Delta was surveyed from past studies. A simple cropping pattern model was described based on the review. In the Delta, after 1990s, desalinization projects that construct tide gates and canals were widely constructed. From the results, past salinity effect pattern that upstream has the stronger influences than the downstream was disappeared. Even, in the downstream, triple cropping rice cultivated. Otherwise, paddy fields are converted into shrimp ponds. These trends can be modeled as the function of farmer's net benefits and income classes. But, in case of high net benefit cropping pattern has high risk of hazard damages. This risk evaluation is the main problem of this modeling.

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[in Japanese]

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The integrated model of geosurface and underground thermal/hydrological circulation has been estimated. This model is based on hydraulic and thermal properties of geosurface and underground. The input data are meteorological data (rain fall, wind velocity, sunshine hours, humidity, air temperature) and the output data as follows - water content of geosurface and underground, pressure (potential) distribution in underground, ground temprature distribution.This model provides regional distribution of evaporation, recharge, discharge, and so on.The validation and evaluation of practicality of the model have been implemented, and this paper shows the concept of the model and the validation result.

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The objective of this study is to evaluate the effects of the design rainfall duration on the design discharge. The 100 - year design rainfalls with various durations are estimated from the relationship between the durations and estimated 100 - year rainfalls. The design hyetographs are generated by means of a random cascade model that is used toprobabilistically disaggregate n - hour rainfall to hyetograph with finer temporal resolution. It is shown that the design rainfall duration have significant effects on design discharge of high coverage ratio and have less significant effects on approximately 50 % coverage ratio in the Doki river basin (106.8 km2).

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The present study aims to estimate spatial distribution of flood damage cost for a large-scale area. For the distributed approach, the land use and the hydrologic characteristics of region were considered. For that purpose, we attempted to combine an economic model for the analysis of economic loss by flood, and a hydrologic model for the analysis of flood inundation. Whole extent of Japan was employed as the objective area. The result showed the economic loss potential by flood according to land use. Moreover, the model has the advantage of the prediction of the flood damage cost by considering the change of precipitation or land use by the climate change or the human activity in the future.

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Safe and adequate drinking water supply is one of the most important basic human needs. Safe drinking water can play a vital role for improvement of primary school enrolment and to make children healthy. However in refugee camps, attention has not been given for improvement of quality of life.
The World Education Forum (Dakar, Senegal, April 2000) emphasised on, "All children have access to and complete, free and compulsory primary education of good quality by 2015". Although countries, International organizations and NGOs have been working to improve school enrolment rate and quality of teaching and learning of primary education in developing countries as well as refugee camps but still there is dire need to adopt strategies to improve primary education. Enrolment rate of primary education in Sub-Saharan Africa is still about 60%. After the Cold War, rapid expansion of globalization has been brought a lot of problems including the smuggling of arms and drugs as well as spreading of infectious diseases. Therefore, even assurance of security for education to achieve universal primary education has been threatened by conflict.
In this study, safe drinking water supply is considered as an entry point for improvement of primary school enrolment rate in refugee camps which play an essential role for sustainable peace and development.

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Water resources and water environment are poor, because Xin Jiang area is almost covered by arid area. National project has been bringing economic development and population increasing in this area. Tarim River, which is one of the longest inland rivers in China, mainly supplies water resources for human society and agricultural activity. River water environment has been damaged by increasing of irrigation water and pollutant load inflow. River water quality management policies should be quickly established for water resources conservation in near future.

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Currently, the severe situation of water consumption in the world still remains unchanged. Though water usage in some developed countries has entered into the stable stage, it is predicted that water usage in developing countries will increase rapidly with rapid development of urbanization.In this study, Japan, US and China was focused on as the represents of developed and developing countries. And this study examined the relation between water usage and the indexes of economy, climate, population, etc in these countries during growing and stable stage. The results showed that although being in the same stable period, the influencing factors in Japan and US were different and it is considered to be due to geographic difference. Therefore in forecasting the future water usage in China's cities which are still in growing period, climatic factors such as precipitation should be important index.

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Industrialization has been advanced worldwide in recent years. The available water on the earth is limited. Industrial water demand will increase and it must be considered that it should be managed appropriately in quantitative respect in the future. Although there are the total amount data of industrial water use in all countries, the domestic distribution of water use in each country is lacked in many cases. In this research, the method for estimation of domestic distribution was investigated. In order to evaluate the availability of the method, the influencing factor was analyzed in the countries which have both total and domestic distribution data. According to these results, the mesh size for establishing global distribution map of industrial water was also investigated.

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[in Japanese]

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[in Japanese]

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