掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/j.ijdrr.2023.103729

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掲載種別：研究論文（学術雑誌）  

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担当区分：責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

日本各地で集中豪雨や台風による被害が増加する中，自主的な避難行動を促すために住民が災害のリスクを適切に認識することが必要である．本研究では，VRを用いて水害の疑似体験が可能なコンテンツを作成するとともに，住民参加のワークショップを通して住民の災害リスク認識，防災意識の変容を検討した．その結果，住民は高潮の浸水認識についてハザードマップの想定と合致する方向に認識するようになった．さらに，避難に関する物や情報の準備，家財を守るといった行動をするタイミングが早くなったり，浸水被害を避けるように避難経路・場所を変更したりするなど防災意識が向上する可能性も示唆された．

DOI： 10.2208/jscejhe.78.2_i_1015

CiNii Research

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担当区分：最終著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

集中豪雨が頻発し，日本各地で甚大な被害をもたらしている中，自主的な避難行動を促すことが被害の抑制に必要である．本研究では，iRICを用いた河川氾濫解析の結果を適用した避難シミュレーションを行い，垂直避難及び，自主避難所の設定の効果の検討を行った．シミュレーションの結果より，垂直避難の有効性，自主避難所への避難が避難完了率を高め，避難が完了するまでの時間を短縮することが確認された．複数の破堤ケースの検証によって，対象河川における避難時のリスクを把握できる可能性を示した．

DOI： 10.2208/jscejhe.77.2_i_1501

CiNii Research

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掲載種別：研究論文（学術雑誌）  

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/jscejhe.77.2_i_1501

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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担当区分：最終著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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担当区分：最終著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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担当区分：最終著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

CiNii Books

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

CiNii Books

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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担当区分：最終著者   記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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担当区分：最終著者   記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

CiNii Books

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejhe.73.I_475

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

DOI： 10.2208/jscejhe.73.I_487

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

DOI： 10.2208/jscejhe.73.I_481

CiNii Books

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

DOI： 10.2208/jscejhe.73.I_469

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejhe.72.I_235

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejhe.72.I_103

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記述言語：日本語   出版者・発行元：水文・水資源学会  

渦相関法を用いた地表面フラックスに関する研究は平原・海上・森林といったフィールドにおいて先行して行われてきたが，1990年代以降，都市域においても渦相関法を用いたフラックスの観測事例が増えてきた．フラックス観測データの蓄積により都市－大気間のエネルギー収支の定量的な把握が進んでいるが，一方，都市における熱収支は裸地や植生におけるそれとは異なる取り扱いが必要であることも明らかになっている．本稿では都市接地層で行われるフラックス観測について，適切な観測サイトの選定方法，観測高度の設定，観測を行う際に留意すべき事項，熱収支の考え方について解説する．また熱収支・CO2 フラックスの時間・季節変化の特徴，発生/吸収源などについて，これまで得られている知見を，著者らの研究を中心にまとめた．最後に，都市版のフラックスネットとして立ち上げられたUrban Flux Networkについて紹介しながら，近年の研究動向などを解説する．

DOI： 10.3178/jjshwr.29.57

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Japan Society of Civil Engineers  

Spatial and temporal distribution of water vapor is important because local severe rainfall is caused by the convergence of water vapor. On the basis of field measurements in the Matsuyama Plain, we found that urban absolute humidity was lower than rural absolute humidity. Following the manner of urban heat island phenomenon, we call this phenomenon "urban dry island" (UDI). The object of this study was to analyze the features and causes of the UDI. The UDI phenomenon was significantly found at daytime during fine days due to the difference in water vapor fluxes at urban and rural sites. The UDI was most prominent in the morning and in the late afternoon, in time zones where the sea breeze and land breeze altered each other and the wind speed temporally became low. Strong sea breeze transported humid air from the coastal regions to the center of the city and then caused the UDI to diminish. The UDI intensity was large in summer and small in winter. This was attributed to the small latent heat fluxes in winter and strong north-westerly monsoon, which enhanced the mixing of humidity. In addition, we investigated the impact of UDI on the formation of clouds using datasets of cloud base level, which was obtained by a ceilometer in summer. Cloud base level over urban areas tended to be higher than that over rural areas under the condition that the wind blew along the border between urban and rural areas. This was demonstrated by lifted condensation level, which was estimated from surface air temperature and water vapor content.

DOI： 10.2208/journalofjsce.1.1_521

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

Estimation of global solar radiation from photovoltaic generation was examined using a dataset of pyranometer and solar panel. The solar panel was equipped horizontally and then tilted at an angle of 20o. In the case of horizontally equipped solar panel, the photovoltaic generation was proportional to global solar radiation and once a calibration parameter was attained using one day in one season, solar radiation estimated from photovoltaic generation using the parameter highly agreed with measured data in other days with correlation more than 0.99. The good performance was not only fair weather days but also for other cloudy days. But the calibration parameter was not universal over other seasons. This is probably due to the difference of solar elevation and/or shade effect. In the case of tilted solar panel, the simple conversion resulted in worse and it was demonstrated that the conversion using direct/scatter separation improved the estimation where the correlation is 0.99. The estimation provided in this study is promising for monitoring of spatial and temporal variation of short wave radiation, because solar panel has been already equipped to a lot of houses and commercial, industrial, and public buildings and the generation data can be easily online-based available.

DOI： 10.2208/jscejhe.71.I_421

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

Spatial and temporal distribution of water vapor is important because local severe rainfall is caused by the convergence of water vapor. On the basis of field measurements in the Matsuyama Plain, we found that urban absolute humidity was lower than rural absolute humidity. Following the manner of urban heat island phenomenon, we call this phenomenon "urban dry island" (UDI). The object of this study was to analyze the features and causes of the UDI. The UDI phenomenon was significantly found at daytime during fine days due to the difference in water vapor fluxes at urban and rural sites. The UDI was most prominent in the morning and in the late afternoon, in time zones where the sea breeze and land breeze altered each other and the wind speed temporally became low. Strong sea breeze transported humid air from the coastal regions to the center of the city and then caused the UDI to diminish. The UDI intensity was large in summer and small in winter. This was attributed to the small latent heat fluxes in winter and strong north-westerly monsoon, which enhanced the mixing of humidity. In addition, we investigated the impact of UDI on the formation of clouds using datasets of cloud base level, which was obtained by a ceilometer in summer. Cloud base level over urban areas tended to be higher than that over rural areas under the condition that the wind blew along the border between urban and rural areas. This was demonstrated by lifted condensation level, which was estimated from surface air temperature and water vapor content.

DOI： 10.2208/journalofjsce.1.1_521

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Matsuyama plain has an obvious contrast of land use in urban and rural area. The purpose of this study is to investigate the effects of differences in land use on the formation of clouds, using the summer time datasets from the observations of cloud base level, solar radiation, surface heat flux, air temperature and humidity. The followings are main outcomes. Cloud base level over urban area was higher than that over rural area when wind blew along the border of the abrupt change of land use. Solar radiation over urban area tended to be smaller than that over rural area in the afternoon of days with a percentage of sunshine ranging from 50% to 80%. This was demonstrated by the development of mixing layer estimated from surface heat flux.

DOI： 10.2208/jscejhe.69.I_1747

J-GLOBAL

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Matsuyama in Ehime Prefecture has often experienced droughts and is one of the water-poorest cities in Japan. The purpose of this study is to analyze the effect of well pumping of groundwater on water resources of the watershed from 1950s to 2010s, using the datasets of groundwater level, river discharge, pumping from wells. The major findings are as follows. The groundwater level and river discharge decreased, while the average precipitation did not change in this term. The volume of water to 9 % of the precipitation in this watershed is pumped up from wells along Shigenobu River. WEP (water and energy transfer process) model, a distributed hydrologic model, shows that the well pumping brings the decrease of the groundwater level in the region from down to middle basin of the river. This agrees well with the fact that the drying up of the river is more extensively observed in recent years compared with that in 1950s.

DOI： 10.2208/jscejhe.69.I_535

J-GLOBAL

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

In recent years much attention has been paid on urban local climate such as heat island phenomenon and severe rainfall. Urban heat island is known as a phenomenon where urban temperature is higher than rural temperature. Whereas investigation for urban heat island phenomenon has been reported in many cities (e. g., Sakakibara et al., 1996), the investigation of water vapor distribution is still poor. Spatial and temporal distribution of water vapor is as important as air temperature, because local severe rainfall is caused by convergence of water vapor. On the basis of field measurements in Matsuyama plain, we found that urban absolute humidity is lower than rural absolute humidity. Following the manner of urban heat island phenomenon, we call the phenomenon 'urban dry island phenomenon'. The object of this study is to analyze the feature and cause of urban dry island phenomenon.

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

We examined the cooling effect of rivers under the conditions where surface water existed and where the water disappeared by drought. The followings were main results. There were differences on the surface temperature of the bridge and air temperature within river channel; they were clearly lower than surroundings under the condition of surface water existence, which was not observed in drought condition. However, air temperature above the bridge tends to be always lower than that of surrounding area. This tendency was consistent regardless of the existence of surface water in the river. The reduction of air temperature above the bridge was often observed under the condition where wind direction matched the direction of stream and where the wind speed was high. The influence of low temperature above the rivers reached around the double of river width in the transverse direction.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

We investigate the spatial characteristics of urban-like canopy flow by applying particle image velocimetry (PIV) to atmospheric turbulence. The study site was a Comprehensive Outdoor Scale MOdel (COSMO) experiment for urban climate in Japan. The PIV system captured the two-dimensional flow field within the canopy layer continuously for an hour with a sampling frequency of 30 Hz, thereby providing reliable outdoor turbulence statistics. PIV measurements in a wind-tunnel facility using similar roughness geometry, but with a lower sampling frequency of 4 Hz, were also done for comparison. The turbulent momentum flux from COSMO, and the wind tunnel showed similar values and distributions when scaled using friction velocity. Some different characteristics between outdoor and indoor flow fields were mainly caused by the larger fluctuations in wind direction for the atmospheric turbulence. The focus of the analysis is on a variety of instantaneous turbulent flow structures. One remarkable flow structure is termed 'flushing', that is, a large-scale upward motion prevailing across the whole vertical cross-section of a building gap. This is observed intermittently, whereby tracer particles are flushed vertically out from the canopy layer. Flushing phenomena are also observed in the wind tunnel where there is neither thermal stratification nor outer-layer turbulence. It is suggested that flushing phenomena are correlated with the passing of large-scale low-momentum regions above the canopy.

DOI： 10.1007/s10546-011-9612-6

Web of Science

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

We investigated the diurnal rainfall variation in Matsuyama plain using datasets from AMeDAS, MLIT, and local government. The evening maximum precipitation is especially remarkable in the inland region and along a river. It is known that a river is street of wind for land and sea breezes. Sea breeze would contribute to an increase in the water vapor content over inland regions through the moist air advection from coastal regions. During the period of 1980-2009, the time when the morning maximum precipitation appears shift two hours later every ten years. Similarly, the offshore land breeze is getting more significant at the rate of 200 ms-1h every ten years.

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

We investigated turbulent flow around building arrays of four different building aspect ratio (H/W) using large eddy simulation. This simulation was aimed to study the similarity of urban canopy flow and plant canopy flow which was expected with the increase of building aspect ratio. As aspect ratio increased, the streamwise flow speed within the urban canopy decreased. Drag coefficient of urban canopy increased with aspect ratio. This is probably due to the increase of frontal area index and the occurrence of transverse flow along the streets. According to quadrant analyses and turbulence statistics, momentum transfer became more efficient as aspect ratio increased. At a high aspect ratio, momentum was more effectively transferred at cross sections than gaps.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER GEOPHYSICAL UNION  

Rainfall interception ( RI) over an outdoor urban-scale model was investigated from the perspectives of water and energy balance. On average, RI was 6% of the gross rainfall and smaller than typical values in forests. No correlation was found between RI and gross rainfall or rainfall duration unlike the correlations found in forests. Most RI occurred in the first several hours of rainfall, and then RI rapidly decreased with time during a rainfall event. RI was dependent on the saturation deficit at the beginning of the rainfall event. The latent heat for RI was approximately balanced by heat conduction from the concrete surfaces. Differences in the canopy structure are considered as possible reasons for the different behaviors of RI between the present site and forests. Accordingly, three aspects of the canopy structure, i.e., effective wet surface area, efficiency for scalar transfer, and canopy heat capacity, are discussed.

DOI： 10.1029/2008WR007069

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER GEOPHYSICAL UNION  

Temporal and spatial variations in anthropogenic water vapor (AWV) emissions and anthropogenic heat (AH) in Tokyo were estimated using data from a geographic information system (GIS) and an energy-consumption database. The maximum value of AWV exceeded 500 W m(-2) in summer in central Tokyo. Estimations of AWV were validated with field-measured data. The estimated and measured data agreed well, indicating that anthropogenic sources such as district cooling systems release large amounts of water vapor into the atmosphere.

DOI： 10.1029/2007WR006624

Web of Science

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出版者・発行元：Japan Society of Civil Engineers  

Particle image velocimetry (PIV) was applied to the turbulent flow within and above an outdoor urban scale model. The setup of the PIV system and the preliminary results were presented. Two dimensional turbulent flow fields in a vertical cross section of street canyon (3 x 3 m) were measured continuously for 60 min; the spatial and temporal resolutions were 5cm and 1/30 sec, respectively. The mean wind vector and turbulent statistics were successfully obtained. Also the PIV results were validated with measurements of ultrasonic anemometer which is conventional instrument for the investigation of atmospheric turbulence. Most of them showed good agreements within the error of 10% although the data aquisition ratio was still low.

DOI： 10.2208/prohe.52.259

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出版者・発行元：Japan Society of Civil Engineers  

To investigate the impact of the actual sea surface temperature (SST) of Tokyo Bay on urban air temperature, an observation network was constructed. SST had been measured at 14 observation sites, such as the lighted buoy in Tokyo Bay since November 2006 to September 2007, and urban air temperature was simulated using the numerical modeling system, WRF, in which SST obtained from this observation was used. In this study, the following results are obtained.<BR>(1) From observational study, spatial distribution of air temperature is similar to that of SST, and air temperature over Tokyo Bay is considerably affected by air advection from the coastal land area.<BR>(2) Actual SST of Tokyo Bay has significant seasonal and diurnal variation compared with outer SST.<BR>(3) Air temperature at Tokyo increases about 0.1°C in summer if the outer SST is replaced with observed SST in Tokyo Bay in the numerical simulation.

DOI： 10.2208/prohe.52.283

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER METEOROLOGICAL SOC  

Urban climate experimental results from the Comprehensive Outdoor Scale Model (COSMO) were used to estimate roughness lengths for momentum and heat. Two different physical scale models were used to investigate the scale dependence of the roughness lengths; the large scale model included an aligned array of 1.5-m concrete cubes, and the small scale model had a geometrically similar array of 0.15-m concrete cubes. Only turbulent data from the unstable boundary layers were considered. The roughness length for momentum relative to the obstacle height was dependent on wind direction, but the scale dependence was not evident. Estimated values agreed well with a conventional morphometric relationship. The logarithm of the roughness length for heat relative to the obstacle height depended on the scale but was insensitive to wind direction. COSMO data were used successfully to regress a theoretical relationship between kappa B-1, the logarithmic ratio of roughness length for momentum to heat, and Re*, the roughness Reynolds number. Values of kappa B-1 associated with Re* for three different urban sites from previous field experiments were intercompared. A surprising finding was that, even though surface geometry differed from site to site, the regressed function agreed with data from the three urban sites as well as with the COSMO data. Field data showed that kappa B-1 values decreased as the areal fraction of vegetation increased. The observed dependency of the bulk transfer coefficient on atmospheric stability in the COSMO data could be reproduced using the regressed function of Re* and kappa B-1, together with a Monin-Obukhov similarity framework.

DOI： 10.1175/JAM2500.1

Web of Science

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出版者・発行元：Japan Society of Civil Engineers  

The interception of rainfall was observed at an outdoor urban scale model site. The model dimensions were 50 x 100 m, with 1.5-m cubic roughness blocks arranged uniformly. The amounts of rainfall and runoff within the area of 6 x 6 m were measured. In this study, we introduced the specification of the facility and preliminary results of rain events which were obtained in September 2006. Mean rainfall intensity of the rainfall events ranged from 0.6 to 1.4 mm hour<SUP>-</SUP><SUP>1</SUP>. Under these rain events, the ratio of runoff to rainfall decreased as the rainfall decreased. This tendency was commonly found in both the total rainfall and the real-time rainfall intensity.

DOI： 10.2208/prohe.51.253

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出版者・発行元：Japan Society of Civil Engineers  

This paper shows the seasonal dependency of vertical profile of air temperature, CO<SUB>2</SUB>, and H<SUB>2</SUB>O within and above a suburban canopy and the turbulent diffusivity of the scalars. The results were derived from field measurements of the vertical profiles and fluxes, which were conducted in a residential area (the mean height of canopy is 7.3 m) of Tokyo, Japan. The vertical profile of CO<SUB>2</SUB> in the daytime drastically varied with the season; the CO<SUB>2</SUB> concentration within the canopy was lower than that above the canopy in summer but was slightly higher in winter. The seasonal change of the daytime CO<SUB>2</SUB> profile is likely due to the effect of photosynthesis by vegetation in backyards. The normalized turbulent diffusivity of air temperature and CO<SUB>2</SUB> depended on height and atmospheric stability, which is similar to that for vegetated canopies. In contrast, the normalized turbulent diffusivity of H<SUB>2</SUB>O was relatively smaller than that of heat and CO<SUB>2</SUB>. Although the correlation coefficients indicated that the transfer efficiencies of CO<SUB>2</SUB> were generally smaller than that of heat, the magnitude of normalized turbulent diffusivity of air temperature and CO<SUB>2</SUB> was almost same.

DOI： 10.2208/prohe.51.271

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：METEOROLOGICAL SOC JAPAN  

This paper describes land-surface parameters, including the roughness lengths of momentum, heat, and water vapor, and the surface moisture availability derived from 1 year of field measurements at a suburban site in Tokyo, Japan. The main results are as follows. The estimated ratio of roughness length of momentum to heat, kB(T)(-1), had an average value of 7. This value of kB(T)(-1) was larger than those documented for vegetated and agricultural surfaces, but less than that reported for a light industrial area. In winter, kB(T)(-1) tended to be smaller, suggesting dependence on the vertical position of the heat source within the canopy. The kB(T)(-1) results also showed a diurnal change, in which higher values occurred in the afternoon. The parameter kB(q)(-1), the ratio of the roughness length of momentum to water vapor, ranged from 40 to 600. The parameter kB(q)(-1) depended on the water vapor deficit, the friction velocity, and the number of elapsed days after precipitation, all of which can change surface water availability. The value of surface moisture availability, beta, ranged from 0.02 to 0.3. beta gradually decreased with the number of elapsed days after precipitation.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

The spatial variability of both turbulent flow statistics in the roughness sublayer (RSL) and temperature profiles within and above the canopy layer (CL) were investigated experimentally in a densely built-up residential area in Tokyo, Japan. Using five towers with measuring devices, each tower isolated from the others by at least 200 m, we collected high-frequency measurements of velocity and temperature at a height z =1.8 z(H), where z(H), the mean building height in the area, is 7.3 m. Also, temperature profiles were measured from z = 0.4 to 1.8 z(H). The 'real mean' geometric parameters that were obtained for the areas within 200 m of each tower were fairly homogeneous among the tower sites. The main results are as follows: (1) The spatial variability of all RSL turbulent statistics, except the sensible heat flux, was comparable to that reported in a pine forest. Also, the variability decreased with increasing friction velocity. (2) The spatial variability of the RSL sensible heat flux was larger than that reported in a pine forest. Also, the variability depended on the time of the day and became larger in the morning. The difference among the sites was well related to the areal fraction of vegetation. (3) The spatial variability of the CL temperature profile depended on the time of the day and became larger in the morning. Nevertheless, the spatial standard deviation of CL temperature was always below 0.7 K. (4) It is suggested that the "warming-up" process in the morning when heat storage is dominant increases the spatial variation of RSL sensible heat flux and CL temperature according to the local properties around each tower and the variation decreases once there is further convective mixing in the midday.

DOI： 10.1007/s10546-006-9063-7

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

We investigated the 'local' and 'global' similarity of vertical turbulent transfer of heat, water vapour, and CO2 within an urban surface layer. The results were derived from field measurements in a residential area of Tokyo, Japan during midday on fair-weather days in July 2001. In this study, correlation coefficients and quadrant analysis were used for the evaluation of 'global' similarity and wavelet analysis was employed for investigating 'local' similarity. The correlation coefficients indicated that the transfer efficiencies of water vapour and CO2 were generally smaller than that of heat. Using wavelet analysis, we found that heat is always efficiently transferred by thermal and organized motions. In contrast, water vapour and CO2, which are passive quantities, were not transferred as efficiently as heat. The quadrant analyses showed that the heat transfer by ejection exceeded that by sweep, and the ratios of ejection to sweep for water vapour and CO2 transfer were less than that for heat. This indicated that heat is more efficiently transferred by upward motions and supported the findings from wavelet analysis. The differences of turbulent transfer between heat and both CO2 and water vapour were probably caused both by the active role of temperature and the heterogeneity in the source distribution of scalars.

DOI： 10.1007/s10546-005-9034-4

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

This study concerns the build-up of carbon dioxide, hereafter CO2, within a suburban canopy under nocturnal stably stratified conditions. The results were derived from wintertime field measurements of the vertical profiles of CO2, air temperature and turbulent exchange processes, in a residential area with a mean canopy height of 7.3 m in Tokyo, Japan. In the daytime, especially under very windy conditions, the CO2 concentration measured at a reference height of 29 in a.g.l. was almost the same as the background CO2 concentration (380ppmv). In contrast, during night-time the CO2 concentration significantly increased under stably stratified conditions. We therefore examined the ensemble mean vertical profile of CO2 concentration using the bulk Richardson number (Rb) as a stability index. Under stably stratified conditions (Rb > 5), the CO2 concentration above the canopy decreased with height such that the difference between within and above the canopy was as high as 40 ppmv. In contrast, the CO2 concentration within the canopy stayed at almost the same level, which indicates that the CO2 emitted from the houses accumulated within the canopy. Such behavior was not found in the H2O profile. We argue that these concentration profiles of CO2 and H2O are influenced by subsiding cold air from the rooftop, thus drawing the high CO, levels from ventilation fans down towards the ground. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.atmosenv.2005.10.059

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Scopus

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出版者・発行元：Japan Society of Civil Engineers  

In urban area, water and heat transfer is not decided only by surface energy balance, but also by artificial effects including waterworks and sewage system. To investigate how water and heat are transferred in urban catchment, meteorological and hydrological values are observed over one year. The catchment is a residential area located in Tokyo metropolitan and the area is 12.2ha. The following results are obtained.<BR>Groundwater from soil into sewer occupies 29% of whole wastewater by evaluating water balance of the catchment. The heat added by water use is up to 3.4 W m<SUP>-2</SUP> in winter and the value is 10% of whole anthropogenic heat. In winter, the heat that the wastewater gains through flowing the catchment is 28% of ground heat flux as a residual heat of surface heat balance.

DOI： 10.2208/prohe.50.511

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DOI： 10.1007/s00704-005-0150-3

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出版者・発行元：Japan Society of Civil Engineers  

The vertical profiles and horizontal distribution of atmospheric turbulence were observed at an outdoor urban scale model site. The model dimensions were 50 x 100m, with 1.5-meter cubic roughness blocks arranged uniformly. Eight sonic anemometers were arranged vertically or horizontally in the site to obtain the vertical profiles or horizontal distribution. In this study, we focused on the atmospheric stability effect on the vertical profiles and the horizontal distribution of the turbulent structure over the model site.<BR>The quadrant analysis was conducted using the data set of the vertical distribution. The analysis showed the dependence of the turbulent motion on the atmospheric stability (z'/L). The sweep mode is mostly dominant at all height in the surface layer when the stability is stable. In case of the unstable atmospheric condition, the ejection mode can crossover the sweep mode at the higher portion in the surface layer.<BR>The streak pattern was observed in a turbulent flow over the building like roughness from the measurement of the horizontal distribution. The width was about 3 or 6 times larger than that of the blocks. This result strongly implies the importance of the horizontal distribution the turbulent structure over urban area.

DOI： 10.2208/prohe.50.445

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出版者・発行元：Japan Society of Civil Engineers  

In this study, we have investigated the fluxes of energy, H<SUB>2</SUB>O and CO<SUB>2</SUB> between the water surface and the atmosphere over Tokyo Bay. And we compared these fluxes with those at a suburban area (Kugahara) in Tokyo, Japan. From recent observations (2004/12-2005/8), the interesting features of energy and scalar fluxes in Tokyo Bay were verified: 1) Sensible heat flux was positive in winter whereas it was negative in summer. 2) Positive latent heat flux was large in winter and it was dependent on wind speed. 3) The CO<SUB>2</SUB> flux in the suburban area was positive (CO<SUB>2</SUB> source), whereas that in Tokyo Bay was negative (CO<SUB>2</SUB> sink). These results were probably due to the advection of air from the urban area.

DOI： 10.2208/prohe.50.463

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出版者・発行元：Japan Society of Civil Engineers  

In this study we focused on the relationships between the vertical profiles of scalar within and above a suburban canopy and the cold-air subsidence locally generated within the canopy. The results were derived from the wintertime field measurements of the vertical profiles of CO<SUB>2</SUB>, air temperature, water vapor, and turbulent flows, which were conducted in a residential area (the mean height of canopy is 7.3 m) of Tokyo, Japan. Under stably stratified conditions, the CO<SUB>2</SUB> concentration above the canopy decreased with height, while that within the canopy kept almost same level. This indicates that the CO<SUB>2</SUB> emitted from the houses accumulated within the canopy. Such behavior was not found in H<SUB>2</SUB>O profile. The vertical profile of air temperature and observations on the surface temperature using a thermal infrared camera suggested that the cold air generated at roof level moved down to the ground level. The effect of 'cold air subsidence' within the canopy is the most plausible reason for the nighttime vertical profiles of CO<SUB>2</SUB> and H<SUB>2</SUB>O.

DOI： 10.2208/prohe.50.493

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

A simple urban energy balance model for mesoscale simulations (SUMM) was tested using results from an outdoor scale-model experiment. The model geometry is assumed to be an infinitely extended regular array of uniform buildings, each of which is composed of six faces (roof, floor, and four vertical walls). The SUMM explicitly considers the three dimensionality of surface geometry and theoretically predicts the energy balance at each face without time-consuming iterations. The SUMM was compared with outdoor scale-model experiments. The simulated energy balance and surface temperatures agree well with the values measured on a reduced-scale hardware model corresponding to the numerical model geometry.

DOI： 10.1007/s10546-004-7956-x

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

The seasonal trend of vertical temperature profiles within and above an urban canopy has been investigated. We measured air temperatures and wind velocities along a 29-m tower in a residential area of Tokyo, Japan continually for 14 months. The height of the daily maximum temperature Z(Tmax) varied with the season; Z(Tmax) was at the roof level in winter but near the ground in summer. The seasonal change of Z(Tmax) is likely due to the change of height at which solar energy is absorbed. At the time of the maximum temperature, the atmosphere above the canopy is always unstable whereas the air within the canopy is unstable in summer but stable in winter.

DOI： 10.1007/s10546-004-5644-5

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出版者・発行元：Japan Society of Civil Engineers  

Based on one year of field measurements, we described the annual fluxes of energy and CO<SUB>2</SUB> at a residential area of Tokyo. The major findings are as follows. 1) The total of <I>Rn</I>, <I>H</I>, and <I>LE</I> was 2.36, 1.35, and 0.90 GJ m<SUP>-2</SUP>, respectively. The latent heat flux <I>LE</I> was large despite the small areal fraction of natural coverage (trees and bare soil). The estimated local latent heat flux per unit natural coverage was two times larger than the available energy (<I>Rn</I>+<I>A</I>), which indicates that the ''oasis effect' was significant. 2) The annual CO<SUB>2</SUB> flux was upward due to fossil fuel consumption in houses and traffic and human bodily exhalations. The total CO<SUB>2</SUB> flux was 3352 gC m<SUP>-2</SUP> and was six times larger than the downward CO<SUB>2</SUB> flux at a typical temperate deciduous forest.

DOI： 10.2208/prohe.49.361

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出版者・発行元：Japan Society of Civil Engineers  

Based on one year of field measurements, we described the annual fluxes of energy and CO<SUB>2</SUB> at a residential area of Tokyo. The major findings are as follows. 1) The total of <I>Rn</I>, <I>H</I>, and <I>LE</I> was 2.36, 1.35, and 0.90 GJ m<SUP>-2</SUP>, respectively. The latent heat flux <I>LE</I> was large despite the small areal fraction of natural coverage (trees and bare soil). The estimated local latent heat flux per unit natural coverage was two times larger than the available energy (<I>Rn</I>+<I>A</I>), which indicates that the ''oasis effect' was significant. 2) The annual CO<SUB>2</SUB> flux was upward due to fossil fuel consumption in houses and traffic and human bodily exhalations. The total CO<SUB>2</SUB> flux was 3352 gC m<SUP>-2</SUP> and was six times larger than the downward CO<SUB>2</SUB> flux at a typical temperate deciduous forest.

DOI： 10.2208/prohe.49.361

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER METEOROLOGICAL SOC  

Based on 1 yr of field measurements, the diurnal, seasonal, and annual fluxes of energy and carbon dioxide (CO2) at a residential area of Tokyo, Japan, are described. The major findings are as follows. 1) The storage heat flux G in the daytime had little seasonal variation, irrespective of significant seasonal change of net all-wave radiation Rn. 2) The latent heat flux in the summer daytime was large despite the small areal fraction of natural coverage ( trees and bare soil). The estimated local latent heat flux per unit natural coverage was 2 times the available energy (Rn - G), which indicates that the "oasis effect'' was significant. 3) The CO2 flux was always upward throughout the year and the magnitude was larger in winter, mainly because of an increase of fossil fuel consumption. The annual total CO2 flux was 6 times the downward CO2 flux at a typical temperate deciduous forest.

DOI： 10.1175/JAM2153.1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Large-eddy simulations have been performed for fully developed turbulent flow within and above explicitly resolved simple cube arrays. The results from our model, hereafter LES-CITY, are shown to agree with laboratory experiments. We investigated the systematic influence of cube density on turbulent flow characteristics by performing numerical experiments for cube areal densities from 0 to 44%. The following results were obtained: (1) The dispersive momentum flux was quite large within the canopy layer due to a mean stream re-circulation, whereas it was smaller above the canopy. The spatial variation of temporally averaged momentum in the roughness sub-layer was 20% or less of the total kinematic surface drag. (2) The temporally and spatially-averaged flow structure confirmed the existence of conventionally described canyon flow regimes; isolated, interfacial, and wake. However, the intermittency of the canyon flow for all cube densities was quite large and the stream patterns were never persistent. (3) Turbulent organized structures (TOS) similar to those observed in turbulent surface-layer flows were simulated, which are characterized by longitudinally-elongated low speed streaks and the corresponding shorter streamwise vortices. The streaks in sparse and dense canopy flows were likely to be aligned to the street line and to the roof lines, respectively. Such heterogeneity of TOS partially accounts for the large spatial variation of momentum flux. (4) In contrast to the mixing layer analogy of vegetation flows, the TOS and the resulting turbulent statistics of urban flow above the canopy resembled those in surface layers. The recirculation within the canopy significantly influenced the turbulent statistical properties.

DOI： 10.1023/B:BOUN.0000027909.40439.7c

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出版者・発行元：Japan Society of Civil Engineers  

We investigate shear functions for momentum (&lt;I&gt;φ&lt;SUB&gt;M&lt;/SUB&gt;&lt;SUP&gt;-1&lt;/SUP&gt;&lt;/I&gt;) and heat (&lt;I&gt;φ&lt;SUB&gt;H&lt;/SUB&gt;&lt;SUP&gt;-1&lt;/SUP&gt;&lt;/I&gt;) and linear correlation coefficients of them (-&lt;I&gt;r&lt;SUB&gt;uw&lt;/SUB&gt;&lt;/I&gt; |&lt;I&gt;r&lt;SUB&gt;wT&lt;/SUB&gt;&lt;/I&gt;|) using data acquired over an urban surface layer in Tokyo Japan. Field measurement was conducted on a 29m height tower, 4 times the canopy height of 7.3m. 3D sonic anemometers were installed at 4 heights in the region 1.5&lt;I&gt;z&lt;SUB&gt;h&lt;/SUB&gt;&lt;/I&gt;&lt;&lt;I&gt;z&lt;/I&gt;&lt;4&lt;I&gt;z&lt;SUB&gt;h&lt;/SUB&gt;&lt;/I&gt; and fine wire thermocouples were mounted at 10 heights from the ground to the top. Main conclusions were obtained as follows.(1) Momentum flux decreases with height. Non-dimensional horizontal wind velocity follows a conventional stratified logarithmic profile when it is scaled by the shear stress extrapolated to the roof top level. However, the locally scaled wind profile fails the agreement.(2) Both of &lt;I&gt;φ&lt;SUB&gt;M&lt;/SUB&gt;&lt;SUP&gt;-1&lt;/SUP&gt;&lt;/I&gt; and -&lt;I&gt;r&lt;SUB&gt;uw&lt;/SUB&gt;&lt;/I&gt; have the dependency on height and they are enhanced near the canopy due to the &#039;bluff body&#039; effect.(3) At a height of &lt;I&gt;z&lt;/I&gt;/&lt;I&gt;z&lt;SUB&gt;h&lt;/SUB&gt;&lt;/I&gt; =2.7, &lt;I&gt;φ&lt;SUB&gt;M&lt;/SUB&gt;&lt;SUP&gt;-1&lt;/SUP&gt;&lt;/I&gt; follows the conventional similarity function while -&lt;I&gt;r&lt;SUB&gt;uw&lt;/SUB&gt;&lt;/I&gt; is still larger than a conventional one. The &#039;bluff body&#039; effect appears more significantly in -&lt;I&gt;r&lt;SUB&gt;uw&lt;/SUB&gt;&lt;/I&gt;.(4) Both of &lt;I&gt;Φ&lt;SUB&gt;H&lt;/SUB&gt;&lt;SUP&gt;-1&lt;/SUP&gt;&lt;/I&gt; and |&lt;I&gt;r&lt;SUB&gt;wT&lt;/SUB&gt;&lt;/I&gt;| have a good agreement with the conventional function and the dependencies on height are not found. In the case of heat, the conventional similarity theory can be applied to the urban surface layer.

DOI： 10.2208/prohe.48.139

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出版者・発行元：Japan Society of Civil Engineers  

The water and energy transport dynamics in urban catchments are investigated to facilitate better understanding of thermo-hydrological impact of urbanization on the receiving water. For this purpose, meteorological and hydrological variables have been monitored in a catchment with an area of 12.2ha located in the central Tokyo District. The amounts and dynamic patterns of urban wastewater showed quite reasonable results compared with existing survey reports. The time variation of sewage temperature showed a distinct diurnal pattern, which reflects water and energy consumption characteristicsin residential houses and is insensitive to a day of the week and season. In a thunderstorm event, the impact of summertime urban heating on the runoff was revealed by an abrupt increase of storm temperature. Finally, a dynamical model was proposed to estimate sewage temperature in response to hydrological and meteorological conditions as well as human behavior of water and energy consumption.

DOI： 10.2208/prohe.48.175

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出版者・発行元：Japan Society of Civil Engineers  

Large Eddy Simulations have been performed for fully developed turbulent flow within and above explicitly resolved simple cube arrays. The model (LES-CITY) was validated in comparison with laboratory experiments. The systematic influence of cubic density on turbulent flow characteristics was investigated through numerical experiments in a wide range of cubic area density (0 to 0.44).&lt;BR&gt;The following results were obtained. 1) The intermittency of flow: the temporally and spatially averaged flow structure confirms the existence of conventionally described canyon flow regime. However, the intermittency of the canyon flow for any cubic densities is large and the stream patterns are never persistent. 2) Turbulent Organized Structures (TOS): TOS are characterized by longitudinally elongated low speed streaks and corresponding streamwise vortices. The streaks in sparse and dense canopy flows are likely to be aligned to the street-line and to the roof-line, respectively.

DOI： 10.2208/prohe.48.607

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出版者・発行元：Japan Society of Civil Engineers  

To investigate the characteristics of potential temperature profiles, a field observation was continuously carried out at a residential site in Tokyo. Following results were obtained; 1) In winter the potential temperature has a maximum value around the roof top level, whereas in summer near the ground surface. The heat source moves up and down due to the seasonal and daily change of solar angle. This isa distinctive characteristic of the micrometeorology of the urban canopy contrast to vegetation canopy. 2) The maximum temperature at the roof top level implies that inversion layer is formed within the canopy. This is directly confirmed by the turbulent flux measurement.

DOI： 10.2208/prohe.48.163

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記述言語：日本語   出版者・発行元：水文・水資源学会  

DOI： 10.3178/jjshwr.16.477

CiNii Books

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記述言語：日本語   出版者・発行元：水文・水資源学会  

DOI： 10.3178/jjshwr.16.491

CiNii Books

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出版者・発行元：Japan Society of Civil Engineers  

To investigate the dependencies of the profiles on the atmospheric stability (z&#039;/L), field measurementsw ere carried out for wind velocity, temperature and turbulent fluxes in and above a dense residential canopy. 1) The vertical profile of wind velocity varies with (z&#039;/L). It deviates from the conventional similarity function in the unstable condition. 2) Momentum flux slowly decrease with height. This tendency is more significant in the unstable condition. 3) Skewness of u above the canopy is larger than the value reported in the vegetation studies. 4) Inversion layer is formed within the canopy around the sunrise due to the local heating of air near the roof top. 5) The gradient of potential temperature under unstable condition is dependent on the atmospheric stability but is relatively larger than the one of the conventional similarity function. 6) The range of roughness sub-layer for heat is smaller than the one for momentum.

DOI： 10.2208/prohe.47.1

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記述言語：日本語   出版者・発行元：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

都市接地層内における熱·水蒸気·CO&lt;SUB&gt;2&lt;/SUB&gt;輸送を把握するため, 東京都大田区久が原の住宅地にて長期観測を行った. フラックスの相関係数を用いてスカラー間の輸送効率を調べたところ, 以下のことが明らかになった. 1) 熱と水蒸気の輸送効率比は, 朝方大きく日中にかけて小さくなる傾向がみられる. 朝方の不安定時は, 大きなスケールの渦構造によって混合層上端からの乾燥空気が連行されることにより, 熱に比べて水蒸気が効率的に輸送されると考えられる. 2) 日中の定常と見なせる時間帯において, スカラー間の相関係数を比較したところ, 熱·水蒸気·CO&lt;SUB&gt;2&lt;/SUB&gt;の順で輸送効率が悪くなる. スペクトル解析·ウェーブレット解析を用いて輸送効率に寄与する渦スケールの特定を行った結果, サーマルやシアー不安定による組織渦が熱, 水蒸気, CO&lt;SUB&gt;2&lt;/SUB&gt;それぞれの輸送を担っている. しかし, これらの輸送イベントの各スカラー量に対する効果は同一ではない. その原因として, スカラー間の濃度分布の不均一性に差異があること, 熱がアクティブなスカラー量であるのに対し水蒸気·CO&lt;SUB&gt;2&lt;/SUB&gt;が受動的なスカラー量であること, が理由として挙げられる.

DOI： 10.3178/jjshwr.16.491

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記述言語：日本語   出版者・発行元：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

東京都大田区久が原の住宅街に気象観測用のタワーを建設して, 放射·熱·水·CO&lt;SUB&gt;2&lt;/SUB&gt;フラックスを測定し1年間の連続データを得た. 晴天日のデータをもとに各フラックスの季節変化や時間変化, および, 潜熱フラックス, CO&lt;SUB&gt;2&lt;/SUB&gt;フラックスに対する都市の構成要素の寄与を調べた. 主要な結果は以下のとおりである. 1) 無視しえない有意な潜熱 (ピーク時で夏季に200W m&lt;SUP&gt;-2&lt;/SUP&gt;, 冬季に30W m&lt;SUP&gt;-2&lt;/SUP&gt;) が都市から放出されている. 夏季は「庭木」が潜熱の主な蒸発源になっていると考えられるが, 200W m&lt;SUP&gt;-2&lt;/SUP&gt;の潜熱全てを庭木で説明しようとすると, 森林の約2倍の潜熱が庭木から放出されていることになる. また「コンクリート」からの潜熱は無視し得ない大きさであり, 特に冬季にはその寄与度が相対的に大きくなる. 2) CO&lt;SUB&gt;2&lt;/SUB&gt;は都市から大気に向けて放出されており, その大きさは夏季より冬季の方が大きい. 夏季はCO&lt;SUB&gt;2&lt;/SUB&gt;フラックスに大きな時間変化はないが, 冬季は8時ころと16∼23時ころにピークが見られる. 特に冬のフラックスはCO&lt;SUB&gt;2&lt;/SUB&gt;濃度の時間変化パターンに似ており, 地表からのフラックスがCO&lt;SUB&gt;2&lt;/SUB&gt;濃度の時間変化に大きく影響している. CO&lt;SUB&gt;2&lt;/SUB&gt;フラックスには「家庭からの人工排出」と「自動車交通」と「庭木」が大きく影響を及ぼす.

DOI： 10.3178/jjshwr.16.477

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DOI： 10.3178/jjshwr.16.477

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Field observations of area-averaged turbulence characteristics were conducted in a densely built-up residential neighbourhood in Tokyo, Japan. In addition to eddy-correlation (EC) sensors a scintillometer was used for the first time in a city. Significant results include: (1) Scintillometer-derived sensible heat fluxes, Q(H), obtained at a height 3.5 times the building height agree well with those using the EC technique; (2) source areas for the scintillometer fluxes are larger than for the EC sensors, so that at low heights over inhomogeneous terrain scintillometry offers advantages; (3) new similarity relationships for dissipation rates are proposed for urban areas; (4) a new technique that uses simultaneous scintillation measurements at two heights to directly estimate area-averaged zero-plane displacement height, z(d), is proposed. z(d) estimated in this way depends slightly on atmospheric stability (lower z(d) under more unstable conditions).

DOI： 10.1023/A:1019668424982

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出版者・発行元：Japan Society of Civil Engineers  

Using the data of the continuous field observation at residential site in Tokyo from March 2001, following results are obtained; 1) The existence of constant-flux layers for momentum, sensible-heat and latent-heat flux above the urban area are confirmed. 2) The probabilities of constant-flux layer achievement (C. F.-rate) are 32.5%, 51.1%, 43.9% and 17.0%, for momentum, sensible-heat, latentheat and carbon dioxide flux, respectively. The C. F.-rate for all fluxes simultaneously is only 0.9%. 3) In this observation site, the C. F.-rate is less affected by the wind direction but slightly related to the atmospheric stability. 4) When a large-scale turbulence or front passes through a sensor, the sensible-heat flux ratio of 29m to 21m is diverted from 1.

DOI： 10.2208/prohe.46.79

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出版者・発行元：Japan Society of Civil Engineers  

Land-surface parameters of urbanized terrain are evaluated based on the field measurement data. Following results are obtained;(1) The value of momentum roughness length (Z&lt;SUB&gt;0&lt;/SUB&gt;) is 1.56m and it is greater than the heat roughness length (z&lt;SUB&gt;T&lt;/SUB&gt;) and water vapor roughness length (Z&lt;SUB&gt;q&lt;/SUB&gt;). The ratios kB&lt;SUB&gt;T&lt;/SUB&gt;&lt;SUP&gt;-1&lt;/SUP&gt;=ln (Z&lt;SUB&gt;0&lt;/SUB&gt;/Z&lt;SUB&gt;T&lt;/SUB&gt;) and kB&lt;SUB&gt;q&lt;/SUB&gt;&lt;SUP&gt;-1&lt;/SUP&gt;=ln (Z&lt;SUB&gt;0&lt;/SUB&gt;/Z&lt;SUB&gt;q&lt;/SUB&gt;) are 8.0 and 20.5 respectively.(2) The value of evaporation efficiency (β) is 0.05-0.2. After precipitation β is significantly decreasing with time for a few weeks. Evaporations from vegetation and concrete material are estimated respectively. Vegetation has a potential to emit latent heat as much as net radiation due to the oasis effect. Concrete material has a potential to cover the β variation range over residential area. When horizontal wind velocity is large, β is decreased.(3) The averaged value of albedo is about 0.13. When there is rainfall, albedo is decreased. But the value is back to about 0.13 within 2-3 days.

DOI： 10.2208/prohe.46.91

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出版者・発行元：Japan Society of Civil Engineers  

The present study uses observational data from a residential site in Tokyo, Japan and a rice paddy in Chiba Pref., Japan, to investigate the relative facility with heat, water vapor, and carbon dioxide are transported by turbulence in the surface layer. The ratios of linear correlation coefficients |rwT/ruw| and |rwq/ruw| increase with stability and the ratios at residential area are generally smaller than at rice paddy due to bluff-body effects. At rice paddy, the ratios of linear correlation coefficient |rwc/rwq| is generally smaller than unity. Meanwhile at the residential area, the distribution of the ratio |rwc/rwq| scatters to |z&#039;/L|. This inequality may be caused by the complex source patterns of the urban surface and the vertical profile within the canopy. Inequalities of transfer between T, c, and q will imply that the diffusion coefficient between them have different value respectively.

DOI： 10.2208/prohe.45.253

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出版者・発行元：Japan Society of Civil Engineers  

This study demonstrates the numerical prediction of thermal sensation index for outdoor environment (SET*OUT) using Regional Atmospheric Modeling System (RAMS). SET*OUT, one of the major thermal sensation index, requires data sets of wind velocity, absolute humidity, air temperature and each component of short wave and long wave radiation in both upward and downward directions. Temporal and spatial variation of SET*OUT over the Kanto Region on August 10 1998 has been presented and discussed. The thermal sensation index for indoor environment (SET*IN) is referred to as a comparison. It is found that the variation of SET*OUT is strongly influenced by mean radiation temperature and sea breeze penetration. The mean radiation temperature, and consequently SET*OUT, have distinctive double peaks in the morning and the afternoon due to the shape factor of cylindrical human body for direct solar radiation. The first peak of SET*OUT in the morning roughly corresponds to the arrival of sea breeze front, and the value is generally larger than that of the second peak in the afternoon. Such a behavior of SET*OUT can be accounted for by the fact that the sea breeze increases wind velocity and activate the heat transfer from human body. SET*IN is similar to but slightly (0.5-1°C) larger than air temperature, which is due to the high humidity condition in Tokyo area.

DOI： 10.2208/prohe.45.259

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

地表面被覆の幾何構造が異なる世田谷・銀座・バンクーバーの3都市のコンスタントフラックス層において超音波風速温度計によって計測された乱流データに基づき, それらの乱流統計量に関して考察がなされた.草原上の観察から得られた既存の相似関数と比較検討し, 以下の結果を得た.(1)運動量に対する熱の鉛直輸送効率を表すそれぞれの乱流相関係数の比は, 大気安定度パラメーターに対して3都市ともほぼ同一の関数で表現されるが, 草原上で得られた既存の相似関数と比べて全般に値が小さい.都市では建物のWake効果あるいは熱源の空間的非均一性により, 運動量の熱に対する相対的な交換効率が草原上よりも高いことが示唆された.(2)主流方向風速の標準偏差, 温度の標準偏差, 乱流運動エネルギー散逸率, および温度分散の散逸率の4つの無次元乱流統計量について, 本論で対象とした都市のコンスタントフラックス層で成立する相似関数式が試算された.

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

密集低層住宅街(世田谷)の接地境界層において, 渦相関法とシンチロメーター法を併用した乱流フラックス観測を行い, 以下の結論を得た.(1)世田谷住宅街における放射収支・熱収支解析データを提示し, その特徴を示した.(2)2高度におけるシンチロメーター計測により, 顕熱と同時にゼロ面変位を推定する手法を提案した.推定されたゼロ面変位は, 平均的にはMacDonald et al.(1998)の形態学的手法から算定された値とほぼ一致した.また, ゼロ面変位が大気安定度に依存することを指摘した.(3)渦相関法とシンチロメーター法の比較により乱流フラックスの空間代表性が検討された.シンチロメーター法のソースエリアは渦相関法のそれに対して, 不安定時で2〜3倍の広さを持つ.30分平均値での顕熱は両手法で有意な差がない.顕熱の標準偏差は大気安定度に関わらずシンチロメーター法の値が小さい.これは計測スパンの長いシンチロメーター法における渦の空間積分効果であると考えられる.

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出版者・発行元：Japan Society of Civil Engineers  

Field observation was performed to investigate the atmospheric structure and concentration of CO&lt;SUB&gt;2&lt;/SUB&gt;, SPM (Suspended Particle Matter) over Tokyo Bay by using Radio Sonde, Doppler Sodar and airplane in summer 1999.&lt;BR&gt;The following results were obtained; 1) There is a descent-flow over Tokyo Bay. The peak value exits at the height of 300m. This expects the existence of circulation flow between Tokyo Bay and surrounding area. 2) The rise in potential temperature in the daytime is caused by the local descent-flow. 3) The vertical and horizontal distribution of SPM and CO&lt;SUB&gt;2&lt;/SUB&gt; is different each other. Vertical gradient of CO&lt;SUB&gt;2&lt;/SUB&gt; is positive over the bay. CO&lt;SUB&gt;2&lt;/SUB&gt; is transported over Tokyo Bay from surrounding high emission area. Vertical gradient of SPM is negative.The profile is affected by the emission of sea-salt at the surface of the bay and Pacific ocean.

DOI： 10.2208/prohe.44.79

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記述言語：日本語  

DOI： 10.2208/prohe.43.233

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DOI： 10.2208/prohe.43.91

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出版者・発行元：Japan Society of Civil Engineers  

Field observation was performed on two islands located in Tokyo Bay to investigate the atmospheric environment over Tokyo Bay by using Radio Sonde, Dopper Sodar and airplane in summer 1998.&lt;BR&gt;The following results were obtained; 1) The atmospheric boundary layer (ABL) over Tokyo Bay was composed of multiple layers.Especially, it was composed of three layers on August 10. 2) These multiple layers were formed by the effect of various kinds of return flows from the land. The upper boundary layer about 1250-2000m over Tokyo Bay was hotter and drier than the one over the land. 3) The airplane observation suggests that the air pollutant might be more concentrated over Tokyo Bay rather than over the land due to the difference of the boundary layer structure.

DOI： 10.2208/prohe.43.233

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出版者・発行元：Japan Society of Civil Engineers  

Three types of experiments on the measurements of spatially mean heat flux were performed by using two sets of scintillometer. In the Case-1, two sets of scintillometer are located adjacently and parallel, in the Case-2, their propagation paths are crossed, and in the Case-3 they are located parallel at the different height. The following results are obtained; 1) the fluctuations of the sensible heat fluxes measured by closely located scintillometer agree with each other, 2) the crossed scintillometer agree well when they are averaged every 30min, but their 1 min-averaged data don&#039;t agree, 3) the method to estimate the regional zero-displacement height &quot;&lt;I&gt;d&lt;/I&gt;&quot; by using two sets of scintillometer is checked and the proper height of &lt;I&gt;d&lt;/I&gt; is derived.

DOI： 10.2208/prohe.43.91

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記述言語：日本語   出版者・発行元：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

神宮の森と同じ植物生理特性を有する人工緑地を関東の各地域に配備した場合に,その緑地が潜在的にどの程度の大気保全効果を有するかを,神宮の森で観測された植物生理特性(神田他,1997a,b)と地域気象モデルのアウトプット(福田他,1997)に基づいて,定量的に見積もり,その地域的差異について論じた.大気保全効果として,ここでは,(1)蒸散量(気候緩和効果),(2)光合成量(CO2同化機能) (3)O3吸収量(大気浄化機能) (4)テルペン放出量(森林浴機能)の4項目を扱った.夏季晴天日を想定した算定結果によれば,都市域では主に飽差の影響(乾燥)により,気孔閉塞が生じやすい傾向にあり,そのため光合成量O3吸収量は山岳域に比べて低くなる.一方,テルペン放出量は葉温が支配的であるため,都市域で大きくなる.蒸散量は,気孔閉塞があるものの,ドライビングフォースとしての飽差が効いて,都市域で若干大きくなる.

DOI： 10.3178/jjshwr.11.498

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記述言語：日本語   出版者・発行元：土木学会  

DOI： 10.2208/jscej.1998.587_109

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

通過交通のあるストリートキャニオンにおける熱収支の実態を把握するために国道246号線において集中観側を行った. また, 通過交通が鉛直乱流混合に与える影響を検討した. その結果, 1) 自動車排熱量は乗用車と普通貨物車に依存しており, 最大で200W/m&lt;sup&gt;2&lt;/sup&gt;に及び, 日平均では日射量を卓越する事, 2) 顕熱の時間変動挙動は純放射量だけでなく, 自動車排熱量にも強く依存している事, 3) 潜熱量が無視し得ない事, 4) シンチレーション法がストリートキャニオンでの顕熱測定に有効である事, 5) 混雑車線が周囲大気に運動量を与えることにより, 鉛直乱流混合に影響を与えている事が明らかになった.

DOI： 10.2208/jscej.1998.587_109

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

明治神宮で行われた集中観測データを森林環境気象モデルに同化させ, 神宮の森の気候緩和機能と大気浄化機能が定量的に評価された. その結果以下の結論が得られた. 1) 数点のポロメーター計測データから未知パラメータを非線形回帰させた気孔コンダクタンスモデルは, 気象学的測定から得られた群落気孔コンダクタンスの傾向をよく表現した. 2 )この気孔特性を森林環境気象モデル (NEO-SPAM2) に同化させて熱収支計算を行ったところ, 実測値を良好に再現した. 3) 神宮の森の気候緩和機能を大きく左右する植物の活性度 (気孔コンダクタンス) は, 樹冠部ほど大きく, 下方へ向かうほど減少している. また植物の活性度は午前中の早い時間帯に最も盛んであることが示された. 4) 本モデルを用いて, 神宮の森における汚染物質吸収量 (鉛直下向きフラックス) を算定したところ, その日中の平均値は, 観測結果と定量的によく一致した. またピーク時のNO_2フラックスを神宮の森全体の面積に換算すると, 乗用車93台分が排出するNO_2量に相当することが明らかとなった. 5 ) また汚染物質吸収は早朝に効率的に行われること, 樹冠付近の葉への吸収が活発なことなど, 観測で得られなかった大気浄化の時空間変動特性が示された.

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

明治神宮の気候緩和機能・大気浄化機能を熱収支・汚染物質吸収量の観点から定量的に把握することを目的として1996年8月に集中観測を行い, 以下の成果が得られた. 1) 神宮の森の放射収支・熱収支が算定された. 正味放射量の約7割は蒸発潜熱に変換されており, 日中に神宮の森が放出する水分量は, 1秒あたり約150kg (ペットボトル100本分) に達する. また都市域の熱収支 (神田ほか, 1997) と比較することにより, 神宮の森の気候緩和機能が定量的に把握された. 2) ポロメーターにより計測される1枚の葉の蒸散・気孔コンダクタンスは, 計測地点の局所的な気象条件の影響を大きく受けるため, そのままでは群落全体の蒸散量に換算できないことが示された. 3) 晴天日の夕方の一般風が弱まる時間帯において, 0.5ms^&lt;-1&gt;以下の弱い森林吹き出し風の存在が示された. 4) 林冠上における汚染物質の鉛直下向きフラックスを傾度法を用いて算定したところ, 日中の平均値として, O_3は約0.30ppb ms^&lt;-1&gt;, NO_2は約0.11PPb ms^&lt;-1&gt;となり, 神宮の森による汚染物質吸収量が定量的に把握された. 5) 神宮の森で測定した汚染物質の濃度変動特性を検討した結果, 物質によりその挙動が異なった. 特にSPM濃度の日変化は夜間にピークをもち, 近接市街地とは逆の傾向を示す. これは夜間森林上に形成される安定層の影響であることが推察された.

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記述言語：日本語   出版者・発行元：水文・水資源学会  

DOI： 10.3178/jjshwr.10.329

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出版者・発行元：Japan Society of Civil Engineers  

The object of this study is to develop a method for estimating both the ground thermometric parameter (ρ c λ) and ground conductive heat flux (G) simultaneously by using the ground surface temperature (Ts). This method is based on the Fourier series expressions of the result of heat transfer equation. The method is tested by a field-measurement. The following results are obtained: 1) The estimated ρ c λ have a reasonable value. 2) Estimated diurnal variations of G agree very well with that observed. 3) The spatial distribution of ρ c λ is also estimated from the surface temperature distribution obtained by the thermo-graphy.

DOI： 10.2208/prohe.41.1097

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記述言語：日本語   出版者・発行元：THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES  

1996年8月に銀座オフィス街において,都市上空の熱収支特性に関する観測を行った.渦相関法とシンチレーション法を併用した計測により,以下の結果を得た.1)銀座オフィス街での熱収支の実態を明らかにし,顕熱・潜熱・蓄熱が同程度の割合で寄与していることを明らかにした.2)都市は顕熱に匹敵する『人工的な潜熱』を出しており,原因として冷房による潜熱放出が有力な候補であることを示した.3)建物側面の窓などからの蓄熱量は無視できない大きさであり,休日の人工熱及び潜熱は平日より少なかった.4)シンチレーション法によるキャノピー上端の顕熱量は,渦相関法によるビル屋上の顕熱とほぼ一致し,ビル屋上での計測の代表性が確認された.4)都市キャノピーにおけるシンチロメータの利用に際しては,ゼロ面変位の算定が重要であることを示し,その決定手法を提案した.

DOI： 10.3178/jjshwr.10.329

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DOI： 10.3178/jjshwr.10.329

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出版者・発行元：Japan Society of Civil Engineers  

The Heat Balance at Meiji-Shrine Forest, where is one of the largest green area in Tokyo Metropolitan, is observed by botha meteorological (MT) and a plant-physiological (PT) method. 70% of net radiation is distributed to latent heat flux. The diurnal variation of evaporation estimated by MT don&#039;t agree qualitatively with that by PT, because the latter is strongly affected by the local meteorological conditions of the sampling site. The characteristics of the stomatal conductance to meteorological conditions can be modeled well by Jarvis equation. The stomatal conductance modified by Jarvis model to exclude the local meteorological conditions, agree very qualitatively with the bulk stomatal conductance estimated by MT.

DOI： 10.2208/prohe.41.43

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出版者・発行元：Japan Society of Civil Engineers  

The photochemical atmospheric pollution is a serious problem. Recently, it is said that biogenic hydrocarbons emitted from forests make some effects on the photochemical reactions, but it has not been confirmed because of the difficulty of measurement. We performed a field observation to estimate the balance of biogenic hydrocarbons, ozone and heat at a forest. The following results are obtained; 1) Ozone concentration over the forest is higher than that under the forest. 2) Biogenic hydrocarbons seems to be closely related to the ozone concentration through photochemical process. 3) The forest acts as a sink of ozone as a whole, but its magnitude is smaller than the ground surface.

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本気象学会  

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記述言語：日本語   出版者・発行元：日本気象学会  

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記述言語：日本語   出版者・発行元：日本気象学会  

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本気象学会  

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

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記述言語：日本語   出版者・発行元：日本気象学会  

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記述言語：日本語   出版者・発行元：日本気象学会  

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記述言語：日本語  

DOI： 10.2208/prohe.52.283

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記述言語：日本語  

DOI： 10.2208/prohe.52.259

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記述言語：日本語   出版者・発行元：水文・水資源学会  

都市の遮断蒸発の動態解明に向け，屋外準実都市模型（以下COSMO）上にて遮断蒸発実験を行った．遮断蒸発量は平均して降雨の6%程度であり，森林域での報告例（10－50％）より小さく，その熱源は晴天時，都市キャノピーに貯えられた熱量であった．また，森林域で報告されているような降雨継続時間・総降雨量の関係は見られなかった一方，降雨初期飽差と強い相関があることが分かった．都市と森林域でのこれらの違いは両者のキャノピー構造の違いに起因することが考察された．つまり，キャノピー構造によって規定される，有効表積率，キャノピー構成要素のサイズ，熱容量の違いが都市と森林の遮断蒸発の絶対量，熱源・支配パラメータに違いをもたらしていると考えられた．

DOI： 10.11520/jshwr.21.0.34.0

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：日本流体力学会  

Particle image velocimetry (PIV) was applied to outdoor turbulent flow within and above urban scale model. This study shows the setup of the PIV system and some preliminary results. The PIV system achieved 60-min continuous measurements with the time resolution of 1/30 seconds for the section of 3x3 meters with the spatial resolution of 5cm. The 2 dimensional distribution of mean wind vector and turbulent statistics were successfully obtained. Also the PIV measurements were validated with measurements of ultrasonic anemometer which is conventional instrument for the investigation of atmospheric turbulence. Most of them showed good agreements within the error of 10%.

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記述言語：日本語   出版者・発行元：日本流体力学会  

Particle image velocimetry (PIV) was applied to outdoor turbulent flow within and above urban scale model. This study shows the setup of the PIV system and some preliminary results. The PIV system achieved 60-min continuous measurements with the time resolution of 1/30 seconds for the section of 3x3 meters with the spatial resolution of 5cm. The 2 dimensional distribution of mean wind vector and turbulent statistics were successfully obtained. Also the PIV measurements were validated with measurements of ultrasonic anemometer which is conventional instrument for the investigation of atmospheric turbulence. Most of them showed good agreements within the error of 10%.

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記述言語：日本語   出版者・発行元：日本流体力学会  

This paper shows the seasonality of vertical profile of air temperature, CO_2, and H_2O within and above a suburban canopy and the turbulent diffusivity of the scalars. The results were derived from field measurements of the vertical profiles and fluxes, which were conducted in a residential area (the mean height of canopy is 7.3m) of Tokyo, Japan. The normalized turbulent diffusivity of air temperature and CO_2 depended on height and atmospheric stability, which is similar to that for vegetated canopies. In contrast, turbulent diffusivity of H_2O was relatively smaller than that of heat and CO_2. H_2O is not efficiently transferred probably because the source of H_2O is localized at the lowest level of urban canopy.

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記述言語：日本語   出版者・発行元：日本流体力学会  

This paper shows the seasonality of vertical profile of air temperature, CO_2, and H_2O within and above a suburban canopy and the turbulent diffusivity of the scalars. The results were derived from field measurements of the vertical profiles and fluxes, which were conducted in a residential area (the mean height of canopy is 7.3m) of Tokyo, Japan. The normalized turbulent diffusivity of air temperature and CO_2 depended on height and atmospheric stability, which is similar to that for vegetated canopies. In contrast, turbulent diffusivity of H_2O was relatively smaller than that of heat and CO_2. H_2O is not efficiently transferred probably because the source of H_2O is localized at the lowest level of urban canopy.

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

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記述言語：日本語   出版者・発行元：日本気象学会  

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記述言語：日本語   出版者・発行元：日本気象学会  

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

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記述言語：日本語   出版者・発行元：日本流体力学会  

CiNii Books

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記述言語：日本語   出版者・発行元：日本流体力学会  

DOI： 10.11426/nagare1982.26.91

CiNii Books

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

This paper shows the seasonal dependency of vertical profile of air temperature, CO<SUB>2</SUB>, and H<SUB>2</SUB>O within and above a suburban canopy and the turbulent diffusivity of the scalars. The results were derived from field measurements of the vertical profiles and fluxes, which were conducted in a residential area (the mean height of canopy is 7.3 m) of Tokyo, Japan. The vertical profile of CO<SUB>2</SUB> in the daytime drastically varied with the season; the CO<SUB>2</SUB> concentration within the canopy was lower than that above the canopy in summer but was slightly higher in winter. The seasonal change of the daytime CO<SUB>2</SUB> profile is likely due to the effect of photosynthesis by vegetation in backyards. The normalized turbulent diffusivity of air temperature and CO<SUB>2</SUB> depended on height and atmospheric stability, which is similar to that for vegetated canopies. In contrast, the normalized turbulent diffusivity of H<SUB>2</SUB>O was relatively smaller than that of heat and CO<SUB>2</SUB>. Although the correlation coefficients indicated that the transfer efficiencies of CO<SUB>2</SUB> were generally smaller than that of heat, the magnitude of normalized turbulent diffusivity of air temperature and CO<SUB>2</SUB> was almost same.

DOI： 10.2208/prohe.51.271

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

The interception of rainfall was observed at an outdoor urban scale model site. The model dimensions were 50 x 100 m, with 1.5-m cubic roughness blocks arranged uniformly. The amounts of rainfall and runoff within the area of 6 x 6 m were measured. In this study, we introduced the specification of the facility and preliminary results of rain events which were obtained in September 2006. Mean rainfall intensity of the rainfall events ranged from 0.6 to 1.4 mm hour<SUP>-</SUP><SUP>1</SUP>. Under these rain events, the ratio of runoff to rainfall decreased as the rainfall decreased. This tendency was commonly found in both the total rainfall and the real-time rainfall intensity.

DOI： 10.2208/prohe.51.253

J-GLOBAL

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記述言語：日本語   出版者・発行元：水文・水資源学会  

本研究では，降雨-流出過程を完全に閉じることが可能な屋外スケールモデル実験サイト上において，降雨-流出の残差から遮断蒸発量を計測するための装置を整備し，降雨中の遮断蒸発量について検討を行った．その結果，以下のことが明らかになった．１）流出率には降雨量依存性があり，雨量が小さいときは流出率が小さくなる．また同程度の降雨量では夏季に流出率が小さくなる傾向がある．２）遮断蒸発量は飽差に大きく依存し，飽差が大きくなるほど遮断蒸発量が増加する．３）夏季は降雨中においても大きい飽差が維持される．負符号の地中熱流量（地中から地表への熱フラックス）は降雨中においても継続しており，この傾向は冬季よりも夏季に顕著に生じる．これが夏季の降雨中の飽差を大きくする原因の一つであると考えられる．

DOI： 10.11520/jshwr.20.0.117.0

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記述言語：日本語   出版者・発行元：The Japan Society of Fluid Mechanics  

DOI： 10.11426/nagare1982.26.91

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：水文・水資源学会  

ヒートアイランド現象や都市型集中豪雨などの都市大気環境問題を抱える首都圏に隣接する東京湾は，これまでに海陸風循環という形で影響を与えていることが指摘されてきたが，その駆動力となる海表面温度変化については詳細には理解されてこなかった．しかしながら，都市気象の現象を考える際，日変化を把握することが非常に重要であるといえる．そこで本研究では，東京湾内湾全域に海表面温度・海上気温の連続自動観測システムを構築し，東京湾が都市大気環境に与える影響を評価する．2006年11月より得られた冬季間の観測結果から，東京湾の海表面温度は潮汐変動に伴う外洋の暖水塊の影響，海上気温は周囲にある陸域の影響を受けている可能性が示唆された．今後も引き続き観測を行い，東京湾が都市気象に与える影響を定量的に評価していく必要がある．

DOI： 10.11520/jshwr.20.0.99.0

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Scopus

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語  

DOI： 10.2208/prohe.50.493

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.50.511

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.50.445

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.50.463

J-GLOBAL

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担当区分：筆頭著者  

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

Based on one year of field measurements, we described the annual fluxes of energy and CO<SUB>2</SUB> at a residential area of Tokyo. The major findings are as follows. 1) The total of <I>Rn</I>, <I>H</I>, and <I>LE</I> was 2.36, 1.35, and 0.90 GJ m<SUP>-2</SUP>, respectively. The latent heat flux <I>LE</I> was large despite the small areal fraction of natural coverage (trees and bare soil). The estimated local latent heat flux per unit natural coverage was two times larger than the available energy (<I>Rn</I>+<I>A</I>), which indicates that the ''oasis effect' was significant. 2) The annual CO<SUB>2</SUB> flux was upward due to fossil fuel consumption in houses and traffic and human bodily exhalations. The total CO<SUB>2</SUB> flux was 3352 gC m<SUP>-2</SUP> and was six times larger than the downward CO<SUB>2</SUB> flux at a typical temperate deciduous forest.

DOI： 10.2208/prohe.49.361

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記述言語：日本語  

CiNii Books

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出版者・発行元：水文・水資源学会  

東京都大田区に位置する低層住宅街にある気象観測タワーを使用し，CO&lt;SUB&gt;2&lt;/SUB&gt;・気温・H&lt;SUB&gt;2&lt;/SUB&gt;O・風速・乱流の鉛直分布を2004年11月_から_12月まで計測した．大気安定度別に各スカラーのプロファイルを検討したころ，都市キャノピー内部で夜間の大気安定時にCO&lt;SUB&gt;2&lt;/SUB&gt;が高濃度化するという興味深い現象を発見した．また気温分布と都市表面温度分布の計測より，屋根面で冷却された空気塊がキャノピー内部に堆積することを示唆する結果が得られた．本研究ではこの冷気流の存在とCO&lt;SUB&gt;2&lt;/SUB&gt;の高濃度化と関連性について考察した．一方，H&lt;SUB&gt;2&lt;/SUB&gt;OはCO&lt;SUB&gt;2&lt;/SUB&gt;と異なる濃度分布を示しており，発生源の位置が濃度分布の形成に重要な役割を持つことを示した．

DOI： 10.11520/jshwr.18.0.113.0

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出版者・発行元：水文・水資源学会  

ヒートアイランド現象をはじめとして都市の大気熱環境に関する研究は数多く行われている一方、水圏への影響に着目した研究は少ない。そこで、都市で発生した熱がどのように水圏へ輸送されるのかを定量的に明らかにするために住宅地における観測を行い、1年間分のデータを蓄積した。この観測より住宅地からの熱の流出過程に関する基礎的データを得たので報告する。対象とした集水域の下水流量のパターンを明らかにし、集水域の下水流量には地下水流入の影響があることが分かった。次に上水水温、下水水温、土壌温度の季節変化から地下水の持つ熱が下水の温度に影響を与えていることを示した。最後に集水域の水・熱収支を考え、地下水の影響を除いた生活排水の水温を求め、住宅地で熱利用に伴って上水に付加された熱量を算出した。

DOI： 10.11520/jshwr.18.0.117.0

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出版者・発行元：水文・水資源学会  

ヒートアイランドや大気汚染といった首都圏が抱えている問題に対し，隣接する東京湾のシンク・ソース機構は重要な役割を果たしていると考えられる．そこで本研究では，都市に隣接する水圏として独特な機能を持つであろう東京湾の特徴を把握するため，東京湾海上にフラックス観測システムを構築し，東京湾!)大気間のエネルギー・CO&lt;SUB&gt;2&lt;/SUB&gt;フラックスの計測を試みた．また，既に都市域で計測されているフラックスとの比較を行った．冬期の観測結果から，都市における潜熱輸送量は日射強制力に因るが東京湾海上では潜熱が非常に大きく風速依存性が強いこと，都市ではCO&lt;SUB&gt;2&lt;/SUB&gt;を常に放出しているが東京湾では吸収する方向に働いていること，東京湾海上での顕熱は都市からの移流によると思われる表面温度と気温の差に対応した日変化が現れるなど，東京湾特有の興味深い知見が得られることを確認できた．今後も連続観測を行い，東京湾の存在意義を定量評価する必要がある．

DOI： 10.11520/jshwr.18.0.114.0

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語  

DOI： 10.2208/prohe.48.139

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.48.175

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.48.607

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.48.163

J-GLOBAL

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担当区分：筆頭著者  

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記述言語：日本語   出版者・発行元：Japan Association for Wind Engineering  

DOI： 10.5359/jawe.2003.97_13

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：Japan Association for Wind Engineering  

DOI： 10.5359/jawe.2003.97_13

CiNii Books

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記述言語：日本語   出版者・発行元：日本風工学会  

DOI： 10.5359/jawe.2003.97_13

CiNii Books

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：社団法人日本気象学会  

CiNii Books

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記述言語：日本語   出版者・発行元：日本気象学会  

CiNii Books

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.47.1

J-GLOBAL

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出版者・発行元：水文・水資源学会  

都市キャノピー内部で発生した物質の乱流拡散には、都市キャノピー内外の温位プロファイルの把握が不可欠である。ストリートキャニオン内においては気温分布が計測されているが、長期間のデータに基づいた都市キャノピー内外での気温分布が報告された例は、筆者の知る限り見当たらない。本報では、低層住宅街に建設した気象観測用タワーによって得られたデータに基づき、都市キャノピー内外の気温プロファイルの形成機構について検討を行う。

DOI： 10.11520/jshwr.16.0.260.0

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出版者・発行元：水文・水資源学会  

近年、都市の幾何形状が上空大気に与える影響が問題となっており研究がなされてはいるが、体系的には理解されていない。また、都市キャノピー層における乱流輸送過程には、都市キャノピー層内部の乱流だけでなく大気境界層の大スケール乱れが影響を及ぼしていることが示唆されている。これらの解決のためには、都市キャノピー層から大気境界層にわたる広範囲な流れの解明が必要である。本研究では、LESモデルを用いて建蔽率を変化させた数値実験を行い、都市キャノピー内部から建物高さの3倍～4倍程度の高さに至る乱流の組織構造を検討した。

DOI： 10.11520/jshwr.16.0.266.0

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出版者・発行元：水文・水資源学会  

メソ気象モデルでは,都市一大気間の熱・エネルギーの乱流交換過程は,平板モデルと同様に取り扱われ,従来から提案されているモニンーオブコフ相似則がそのまま拡張適用されている．風洞実験により建物模型キャノピー内外の乱流特性が調べられているが,フィールドに拡張する際に不可欠である大気安定度依存性にまで言及しているものは数少なく,平原や森林で数多く提案されているモニンーオブコフ相似則が,都市においても適用できる保証はない．本報では住宅街でのタワー観測による運動量フラックスと風速勾配の関係およびシアー関数について検討した．

DOI： 10.11520/jshwr.16.0.262.0

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本流体力学会  

A long-term field measurement is performed to investigate turbulent transfers in a densely built-up urban surface layer. The ratios of fluxes measured at two heights are almost unity. We can expect the existence of the surface layer in this residential area. The turbulent transfer efficiencies of momentum, heat, vapor, and CO_2 are examined. Following results are obtained; 1) The ratio for heat/momentum is smaller the results in Kansas experiment. This behavior is expected over an urban surface where form drag due to bluff-body effects of buildings increases the transfer efficiency of momentum compared to scalar transfers. 2) The transfer efficiencies of vapor and CO_2 are smaller than that of heat. 3) Wavelet analysis shows this reason. Thermal structures and organized structures transfer heat efficiently. Vapor and CO_2 are also transferred as well as heat by some structures. But they are not or adversely transferred by other structures.

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

CiNii Books

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

CiNii Books

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記述言語：日本語   出版者・発行元：日本流体力学会  

A long-term field measurement is performed to investigate turbulent transfers in a densely built-up urban surface layer. The ratios of fluxes measured at two heights are almost unity. We can expect the existence of the surface layer in this residential area. The turbulent transfer efficiencies of momentum, heat, vapor, and CO_2 are examined. Following results are obtained; 1) The ratio for heat/momentum is smaller the results in Kansas experiment. This behavior is expected over an urban surface where form drag due to bluff-body effects of buildings increases the transfer efficiency of momentum compared to scalar transfers. 2) The transfer efficiencies of vapor and CO_2 are smaller than that of heat. 3) Wavelet analysis shows this reason. Thermal structures and organized structures transfer heat efficiently. Vapor and CO_2 are also transferred as well as heat by some structures. But they are not or adversely transferred by other structures.

CiNii Books

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記述言語：日本語  

CiNii Books

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記述言語：日本語  

CiNii Books

J-GLOBAL

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記述言語：日本語  

CiNii Books

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記述言語：日本語  

CiNii Books

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.46.79

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/prohe.46.91

J-GLOBAL

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記述言語：英語   出版者・発行元：AMER METEOROLOGICAL SOCIETY  

Web of Science

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記述言語：日本語   出版者・発行元：水文・水資源学会  

DOI： 10.11520/jshwr.15.0.204.0

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

CiNii Books

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

The present study uses observational data from a residential site in Tokyo, Japan and a rice paddy in Chiba Pref., Japan, to investigate the relative facility with heat, water vapor, and carbon dioxide are transported by turbulence in the surface layer. The ratios of linear correlation coefficients |rwT/ruw| and |rwq/ruw| increase with stability and the ratios at residential area are generally smaller than at rice paddy due to bluff-body effects. At rice paddy, the ratios of linear correlation coefficient |rwc/rwq| is generally smaller than unity. Meanwhile at the residential area, the distribution of the ratio |rwc/rwq| scatters to |z'/L|. This inequality may be caused by the complex source patterns of the urban surface and the vertical profile within the canopy. Inequalities of transfer between T, c, and q will imply that the diffusion coefficient between them have different value respectively.

DOI： 10.2208/prohe.45.253

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

This study demonstrates the numerical prediction of thermal sensation index for outdoor environment (SET*OUT) using Regional Atmospheric Modeling System (RAMS). SET*OUT, one of the major thermal sensation index, requires data sets of wind velocity, absolute humidity, air temperature and each component of short wave and long wave radiation in both upward and downward directions. Temporal and spatial variation of SET*OUT over the Kanto Region on August 10 1998 has been presented and discussed. The thermal sensation index for indoor environment (SET*IN) is referred to as a comparison. It is found that the variation of SET*OUT is strongly influenced by mean radiation temperature and sea breeze penetration. The mean radiation temperature, and consequently SET*OUT, have distinctive double peaks in the morning and the afternoon due to the shape factor of cylindrical human body for direct solar radiation. The first peak of SET*OUT in the morning roughly corresponds to the arrival of sea breeze front, and the value is generally larger than that of the second peak in the afternoon. Such a behavior of SET*OUT can be accounted for by the fact that the sea breeze increases wind velocity and activate the heat transfer from human body. SET*IN is similar to but slightly (0.5-1°C) larger than air temperature, which is due to the high humidity condition in Tokyo area.

DOI： 10.2208/prohe.45.259

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記述言語：日本語   出版者・発行元：日本気象学会  

地表面被覆の幾何構造が異なる世田谷・銀座・バンクーバーの3都市のコンスタントフラックス層において超音波風速温度計によって計測された乱流データに基づき, それらの乱流統計量に関して考察がなされた.草原上の観察から得られた既存の相似関数と比較検討し, 以下の結果を得た.(1)運動量に対する熱の鉛直輸送効率を表すそれぞれの乱流相関係数の比は, 大気安定度パラメーターに対して3都市ともほぼ同一の関数で表現されるが, 草原上で得られた既存の相似関数と比べて全般に値が小さい.都市では建物のWake効果あるいは熱源の空間的非均一性により, 運動量の熱に対する相対的な交換効率が草原上よりも高いことが示唆された.(2)主流方向風速の標準偏差, 温度の標準偏差, 乱流運動エネルギー散逸率, および温度分散の散逸率の4つの無次元乱流統計量について, 本論で対象とした都市のコンスタントフラックス層で成立する相似関数式が試算された.

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記述言語：日本語   出版者・発行元：日本流体力学会  

Field observation and numerical simulations were performed to investigate the atmospheric structure and distribution of air pollutants over Tokyo Bay. The following results were obtained : 1) Observed diurnal variation of potential temperature over Tokyo Bay is different from over the land or the sea. 2) There is a descending flow over Tokyo Bay. and it is the compensation for the divergent flow pattern. The peak value of descending flow exits at the height of 300-500m. 3) The rise in potential temperature in the daytime is caused by the adiabatic heating of descending flow. 4) Vertical gradient of CO_2 is positive over the bay. It suggests that CO_2 is transported over Tokyo Bay from surrounding high emission area.

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記述言語：日本語   出版者・発行元：日本気象学会  

密集低層住宅街(世田谷)の接地境界層において, 渦相関法とシンチロメーター法を併用した乱流フラックス観測を行い, 以下の結論を得た.(1)世田谷住宅街における放射収支・熱収支解析データを提示し, その特徴を示した.(2)2高度におけるシンチロメーター計測により, 顕熱と同時にゼロ面変位を推定する手法を提案した.推定されたゼロ面変位は, 平均的にはMacDonald et al.(1998)の形態学的手法から算定された値とほぼ一致した.また, ゼロ面変位が大気安定度に依存することを指摘した.(3)渦相関法とシンチロメーター法の比較により乱流フラックスの空間代表性が検討された.シンチロメーター法のソースエリアは渦相関法のそれに対して, 不安定時で2～3倍の広さを持つ.30分平均値での顕熱は両手法で有意な差がない.顕熱の標準偏差は大気安定度に関わらずシンチロメーター法の値が小さい.これは計測スパンの長いシンチロメーター法における渦の空間積分効果であると考えられる.

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記述言語：日本語  

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記述言語：日本語  

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記述言語：日本語  

DOI： 10.2208/prohe.44.79

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記述言語：日本語  

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：日本流体力学会  

DOI： 10.11426/nagare1982.18.101

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記述言語：日本語   出版者・発行元：日本流体力学会  

DOI： 10.11426/nagare1982.18.101

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記述言語：日本語  

CiNii Books

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記述言語：日本語  

CiNii Books

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記述言語：日本語  

CiNii Books

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記述言語：日本語  

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記述言語：日本語  

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

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記述言語：日本語  

DOI： 10.2208/prohe.43.91

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記述言語：日本語  

DOI： 10.2208/prohe.43.233

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記述言語：日本語   出版者・発行元：The Japan Society of Fluid Mechanics  

DOI： 10.11426/nagare1982.18.101

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

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記述言語：日本語  

明治神宮の気候緩和機能・大気浄化機能を熱収支・汚染物質吸収量の観点から定量的に把握することを目的として1996年8月に集中観測を行い, 以下の成果が得られた. 1) 神宮の森の放射収支・熱収支が算定された. 正味放射量の約7割は蒸発潜熱に変換されており, 日中に神宮の森が放出する水分量は, 1秒あたり約150kg (ペットボトル100本分) に達する. また都市域の熱収支 (神田ほか, 1997) と比較することにより, 神宮の森の気候緩和機能が定量的に把握された. 2) ポロメーターにより計測される1枚の葉の蒸散・気孔コンダクタンスは, 計測地点の局所的な気象条件の影響を大きく受けるため, そのままでは群落全体の蒸散量に換算できないことが示された. 3) 晴天日の夕方の一般風が弱まる時間帯において, 0.5ms^<-1>以下の弱い森林吹き出し風の存在が示された. 4) 林冠上における汚染物質の鉛直下向きフラックスを傾度法を用いて算定したところ, 日中の平均値として, O_3は約0.30ppb ms^<-1>, NO_2は約0.11PPb ms^<-1>となり, 神宮の森による汚染物質吸収量が定量的に把握された. 5) 神宮の森で測定した汚染物質の濃度変動特性を検討した結果, 物質によりその挙動が異なった. 特にSPM濃度の日変化は夜間にピークをもち, 近接市街地とは逆の傾向を示す. これは夜間森林上に形成される安定層の影響であることが推察された.

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記述言語：日本語  

明治神宮で行われた集中観測データを森林環境気象モデルに同化させ, 神宮の森の気候緩和機能と大気浄化機能が定量的に評価された. その結果以下の結論が得られた. 1) 数点のポロメーター計測データから未知パラメータを非線形回帰させた気孔コンダクタンスモデルは, 気象学的測定から得られた群落気孔コンダクタンスの傾向をよく表現した. 2 )この気孔特性を森林環境気象モデル (NEO-SPAM2) に同化させて熱収支計算を行ったところ, 実測値を良好に再現した. 3) 神宮の森の気候緩和機能を大きく左右する植物の活性度 (気孔コンダクタンス) は, 樹冠部ほど大きく, 下方へ向かうほど減少している. また植物の活性度は午前中の早い時間帯に最も盛んであることが示された. 4) 本モデルを用いて, 神宮の森における汚染物質吸収量 (鉛直下向きフラックス) を算定したところ, その日中の平均値は, 観測結果と定量的によく一致した. またピーク時のNO_2フラックスを神宮の森全体の面積に換算すると, 乗用車93台分が排出するNO_2量に相当することが明らかとなった. 5 ) また汚染物質吸収は早朝に効率的に行われること, 樹冠付近の葉への吸収が活発なことなど, 観測で得られなかった大気浄化の時空間変動特性が示された.

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

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記述言語：日本語  

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記述言語：日本語  

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

The Heat Balance at Meiji-Shrine Forest, where is one of the largest green area in Tokyo Metropolitan, is observed by botha meteorological (MT) and a plant-physiological (PT) method. 70% of net radiation is distributed to latent heat flux. The diurnal variation of evaporation estimated by MT don't agree qualitatively with that by PT, because the latter is strongly affected by the local meteorological conditions of the sampling site. The characteristics of the stomatal conductance to meteorological conditions can be modeled well by Jarvis equation. The stomatal conductance modified by Jarvis model to exclude the local meteorological conditions, agree very qualitatively with the bulk stomatal conductance estimated by MT.

DOI： 10.2208/prohe.41.43

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

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記述言語：日本語   出版者・発行元：東京工業大学工学部土木工学科  

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記述言語：日本語  

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