Diurnal variations of surface wind speeds during fair weather in the summer were revealed in central Japan, including data at Automated Meteorological Data Acquisition System (AMeDAS) and mountain station data above 2000 m above the mean sea level (a.s.l.) archived by an inter-university cooperative project, in relation to the altitude and concave-convex conditions around each station. AMeDAS stations belonging to Japan Meteorological Agency (JMA) are located below 1500 m, and most of them were categorized as being in concave topography with stronger daytime wind speed anomalies than in nighttime. At stations above 2000 m a.s.l. operated by each university, wind speed anomalies at night were stronger than those during the day except at the station without convex topography within a 1-5 km scale. Nocturnal enhancement of wind speeds at representative mountaintop stations appeared with prevailing Pacific Highs in synoptic pressure patterns, but it did not always appear in the same day and the absolute nocturnal wind speed varied day by day. The degree of concavity was not clearly related to the wind speed anomaly, and the degree of convexity was linearly related to the wind speed anomaly at a scale of approximately 10 km.

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As urbanization progresses, the outdoor thermal environment is deteriorating due to the decrease of vegetation and increase of constructed surfaces. Environmental problems such as the heat island phenomenon occur not only in large cities but also in mid-sized and small cites. Increasing tree or vegetation plantings is one of the most effective strategies to mitigate environmental problems and create a comfortable living environment. In this study, the microclimatic effect of a windbreak forest surrounding a residence was analyzed based on field measurements and numerical simulation results. Spherical thermographs of surface temperature distribution observed in an actual residence were used to identify the thermal effect of the windbreak forest and surface materials. A coupled numerical simulation method of computational fluid dynamics (CFD) and outdoor thermal simulation was used to evaluate the microclimate and thermal comfort in outdoor living spaces. The proposed simulation method was validated by comparing the simulated results with the measurement data. In addition, the residence was modeled using the coupled simulation program to quantify the microclimate and outdoor thermal comfort. Simulation results show that this simulation method is capable of predicting the solar shading effect and wind speed reduction due to trees as well as thermal improvement from decreased ambient air temperature and surface temperature.

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An analysis of the diurnal variation of precipitable water and convective activity was conducted for days around Mt. Tanigawa. Precipitable water and convective activity exhibited a pronounced diurnal variation, with dual maxima in the daytime (10-14 JST), and in the evening (18-22 JST), and these maxima of convective activity almost coincided with maxima of precipitable water. The mechanism responsible for the diurnal variation with dual maxima of precipitable water and convective activity, was discussed using GPS network data, and the findings of Iwasaki and Miki (2001 and 2002). The process of diurnal variation with dual maxima of precipitable water, around Mt. Tanigawa can be divided into 4 periods.
1) Late night to early morning: Precipitable water decreases due to large scale subsidence associated with a Pacific High, and the large scale subsidence persists throughout analysis period even in the daytime; 2) Early morning to noon: As a valley-wind circulation develops, moisture transport from the semi-basin (valley) to the mountain also becomes active. Because the effect of the moisture transport exceeds the effect of the large scale subsidence, precipitabe water around Mt. Tanigawa begins to increase gradually; 3) Noon to around 15 JST: Because the atmosphere in the valley becomes dry due to the compensating downdraft of the valley-wind circulation, the moisture transport from the semi-basin to the mountain decreased. The effect of large scale subsidence exceeds the effect of the moisture transport, so that precipitable water decreases in the daytime; and, 4) Around 15 JST to late night: Precipitable water is recovered due to moisture convergence from the socalled “extended sea breeze,” and moisture advection from the mountains, located on the windward side of Mt. Tanigawa.
An increase of precipitable water in the daytime, and the evening, must work to unstabilize atmosphere, and surface heating, due to solar radiation that enhances the instability in the daytime. These effects contribute to formation, and/or development, of Cb groups in the daytime and the evening around Mt. Tanigawa.

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The relationship between the diurnal variation of convective activity and precipitable water was examined in summer seasons using water vapor radiometer, C-band radar and radiosonde data. Convective activity over the “semi-basin” exhibited a diurnal variation with dual peaks at 15-17 JST and 19-20 JST, and the SSI (Showalter Stability Index) decreased from morning to evening due to the increase of water vapor in the lower layers associated with a thermally induced local circulation.
When precipitable water exhibited a pronounced diurnal variation, the evening convective activity maximum (19-20 JST) was evident and cumulonimbus clouds had a tendency to develop over a limited region south and east of Mt. Haruna. On average the convective activity maximum occurred about an hour before the precipitable water maximum, and when precipitable water reached a maximum at an early (late) time, cumulonimbus clouds also formed at an early (late) time. Furthermore, the mechanism responsible for the evening convective maximum over the “semi-basin” is discussed, based on the results of the diurnal variation of convective activity and precipitable water.

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The purpose of this study is to clarify the effects on reducing temperature by improving the pavements and planting turf or trees. The "water retention pavement" and the "reflective and permeable pavement" were settled on the car park. Turf with protecting material against the weight of cars was planted on another area. In addition to these three types of surfaces, gravel surface, regular asphalt and the area under shading trees were selected as other three types of surfaces. Surface temperature and underground temperature at 7cm depth were measured at those six types of the surface areas during summer in 2008. The lowest temperature was observed at the area under the shading tree. The next lower area was the turf. At the area of the "water retention pavement" and the "reflective and permeable pavement", the temperature were about 17degree C higher than the area under the shading tree, but about 10degree C lower than the area of the regular asphalt pavement at the hottest hours in mid summer. The globe temperatures were measured by using globe thermometers. The globe temperatures under the shading trees were almost as same as the air temperature. But the difference of globe temperature between the area under the shading tree and other area were more than 10degree C during mid day hours in days.

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Surface energy-balance closure in a typical gully region of the Loess Plateau on the eastern edge of Qinghai-Xizang Plateau were studied based on the turbulence and radiation data observed at the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL) in a period of 6 consecutive sunny days for each month from June to August 2008. The results show that the sensible heat flux considering the vertical advection item of energy transport to the energy budget equation (H_ec + H_mv) in the gully region on summer sunny days accounted for 39.4% of net radiation, and the surface soil heat flux considering the heat storage term from the surface to the flux-plate (G + ΔG) for 29.6%, and the latent heat flux (LE) account for 26.5%, after all corrections. The closure rate of surface energy for the typical environment of the Loess Plateau reached 93.2% and was higher during the day than at night. Consideration of soil heat storage (ΔG) and the vertical advection effect (H_mv) significantly improved the surface energy closure rate. It is seen that in the typical semi-arid Loess Plateau region, even in the rainy season, sensible heat is still dominant over various components of surface energy expenditure.

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The results of laboratory measurements on the performance of the HVAC system powered by solar air heater, solar cell and wind generator, are described. Experiments were performed in various weather conditions both in winter and summer. The experimental results show that 30-90% of thermal energy to regenerate the desiccant in this system and 20-65% of the energy to power the system were supplied by natural energy in summer, and 30-97% of the energy to power the system was supplied by natural energy in winter. The results of measurements on the performance of a desiccant dehumidifier unit with solar air collectors are also described. Room exhaust air is used to cool the 17% of the desiccant rotor area in this unit. Experimantal results show that the amount of dehumidification was increased by 6% and the amount of energy to cool the air was decreased by 8% by this rotor cooling process.

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The results of measurements on the performance of a desiccant dehumidifier unit with solar air collectors are described. Room exhaust air is used to cool the 17% of the desiccant rotor area in this unit. Experimental results show that the amount of dehumidification was increased by 6% and the amount of energy to cool the air was decreased by 8% by using this rotor cooling process. Results also show that the outlet temperature of the solar air collectors in summer was more than 80℃ which is effective in regenerating the desiccant in this system and more than 50% of the thermal energy to regenerate the desiccant was supplied by the solar air collectors in a day.

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The horizontal air temperature profile of Lake Inawashiro, Fukushima Prefecture, was observed on July 7th, 1963, a day. A high temperature area was found over the center of the lake (Fig. 2) when lake breezes developed. The development of this high temperature area is explained by the subsidence of relatively warm air from the higher levels, probably caused in part by the development of a small anticyclonic wind system and in part by vertical air circulation over the lake. The air is cooled as it advances shoreward over the lake surface, producing the air temperature profile over the land shown in Figure 3.

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施設栽培された夏作,冬作の温室メロンの蒸発散量を比較測定し,気象要因,植物要因が蒸発散量の生育時期別変化および日変化に及ぼす影響を検討した.生育時期別の蒸発散量は,定植から開花後1週間まではS字型曲線で示すことができ,その後は果実生長にともなって徐々に低下した.定植から収穫までの全蒸発散量は1株当たり夏作116kg,冬作60kgであり,日蒸発散量の最大値はそれぞれ3.0kg, 1.3kgであった.蒸発散量は生育初期には葉面積の増加につれ急増し,着果以降は葉の蒸散能力の低下につれて低下した.そのため,かん水量は葉面積の増加につれ増やし,果実の生長につれ減らす必要がある.日射量,飽差,蒸発散量の日変化をみると,夏季晴天日においては日射量は正午ころ最大となるが,飽差はそれより遅れて最大となった.そのため,午後の蒸発散量は午前の蒸発散量に比べて大きくなった.冬季においては,飽差について特徴的変化が認められた.すなわち,夕方から早朝にかけての飽差は暖房により高く,昼間の飽差は低換気率のため低くなった.これにより,蒸発散量と飽差との相関は低くなった.回帰分析の結果,蒸発散量に影響する主要な気象要因は日射量であることが認められた.

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1985年夏季の晴天条件下に中部日本域で発生した短時間降雨を、ルーチン気象観測データを用いて統計的に解析した。解析期間の中部日本域における降水量は夕方の18時ぐらいに顕著なピークを持ち、0時から12時までの深夜から午前中にかけての時間帯にはほとんど降水がなかった。夕方の顕著な降水ピークは、午後になって発生する驟雨性の短時間降雨に対応したものである。日々のデータについて見ると、このような降雨は可降水量40mm以上の気象条件下で発生しやすくなり、その活動度は乾燥(または湿潤)対流に対する大気安定度の減少にともなって増加していた。短時間降雨の降雨域は内陸の山岳地帯に集中しており、降雨頻度が高い地域の時間による移動はあまり大きくなかった。ただし降雨域の山岳への集中の程度は,短時間降雨の活動が活発な日ほど小さくなる傾向があった。
一方、中部日本域では春季から夏季にかけての一般風が弱い晴天日の日中に、連日のように熱的な局地循環低が発達する。熱的局地循環は地形の影響を強く受けており、内陸の山岳が局地循環の顕著な収束域となっていた。以前に実施された研究によって、熱的局地循環が平野および盆地(盆地底)から山岳に水蒸気を輸送する働きを持つことと、中部日本域のような100km程度の水平スケールを持つ地形で、夕方における山岳上での水蒸気の蓄積が最大となることが明らかになっている。すなわち内陸の山岳では水蒸気の蓄積によって午後になると積雲が生成しやすくなり、今回の地上気象データの解析からも、午後の山岳域における水蒸気量の増加と日照率の低下が認められた。実際の短時間降雨にともなった降雨域もこのような山岳域に集中しいることから、熱的局地循環の発達が夏季の中部日本における対流性降雨の発生のトリガーとなっている可能性が本解析により示唆されたといえる。

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A trap for capturing Monochamus alternatus adults alive was devised by adding a plastic funnel to a commercial attraction trap. The funnel was set in a bucket to prevent collected adults from escaping. About 30% of collected beetles escaped from buckets with funnels per day on average under experimental conditions. Twenty-one traps were set in pine stands and captured beetles were collected every 3-4 days. The escape ratio during each census period was estimated at 34-56%, corresponding well to the value estimated from the laboratory experiment. On days, the temperature in the buckets reached 45-49°C, which seemed to be lethal to the beetles. The maximum temperature in buckets covered with aluminum foil was about 6°C lower than in the uncovered bucket, but was still too hot to keep captured beetles alive.

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At Lake Noziri, the writers made the observations of the vertical distribution of the hydrogen ion concentration etc. on July 25, September 9, and September 22 of 1965.
On July 25, when the rainy season just ended, the writers observed no layer where the lake water is more alkaline than that of any other layer. After the day, weather lasted, and on September 9, they observed an alkaline layer (pH=8.1) conspicuously developed as hitherto observed, in the thermocline of the lake. The writers think the development of the alkaline layer to be attributed partly to the enough radiation of the sun.
On September 22, however the disappearance of the alkaline layer was observed, the writers consider this phenomenon to be attributed to the circulation, though imperfect, of the lake water caused by heavy rainfall accompanied with the typhoons which had passed before the time of the last observation, near the lake.

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Despite growing recognition of post-race exertional heat illness (EHI) in the horse racing industry, reports on its prevalence are limited. The purpose of this study was to investigate the prevalence of post-race EHI and climate conditions at racecourses in Japan. The overall prevalence of EHI from 1999 to 2018 was 0.04% (387 cases for 975,247 starters) in races operated by the Japan Racing Association (JRA). The yearly prevalence has been increasing, exceeding 0.07% in the last four years of the studied period. The overall prevalence in summer (May–September) was 0.086% (352 cases for 409,908 starters). The monthly prevalence varied among the 10 JRA racecourses, which are distributed from latitude 34 to 43°N, ranging from no cases to 0.459%. During summer, prevalence of post-race EHI was high when the mean monthly ambient temperature was high at a racecourse. To evaluate climate conditions, we investigated the wet-bulb globe temperature (WBGT, °C) from 9 AM to 5 PM on sunny race days in July and August of 2017 and 2018 at three racecourses with a high prevalence of EHI among the 10 racecourses. The durations of time during which WBGT was between 28 and 33°C at these three courses were 95, 94, and 65% of the minutes measured, respectively. This result indicated that most races on the

days were held when WBGT was between 28 and 33°C at the three racecourses. These findings could be useful in developing the appropriate countermeasures to be taken during hot weather at each of the studied racecourses.

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A method for computing photosynthesis rate of a tree using realistic plant models, AMAP, is discussed in this paper. Photosynthetic rate calculation is an important factor to estimate the growth rate of plants and landscape dynamics in green spaces. However, photosynthesis of plants is difficult to compute because of plants' complex three-dimensional structures composed of leaves, branches and trunks. Complicated structure makes it hard to quantify irradiation intensity caught by each leaf, which is a major factor to define photosynthetic rate. On another front, simulation models which recreate a plant structure inside computer make progress. This enables simulating light acquisition of leaves by ray-tracing methods. Accordingly we compute photosynthesis rate in a

day using AMAP plant models. The results show that photon weight for ray-tracing greatly influence the amount of photosynthesis rate, and should be set carefully according to target scale. And these calculations suggest that an impact of light shading by branches is slightly large. This method can be applied to a simulation of plants dynamics, for example. And such a simulation will be expected to offer new insights of the landscape managements.

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The results of numerical simulation on the effects of solar chimney system combined with underground coolth for ventilation and cooling in a four storied new school building in Kitakyushu are described. The inside surface temperatures of four walls of solar chimney were estimated using the outside temperature and solar radiation in summer. The air velocity and pressure within the solar chimney were estimated by simplified method and CFD calculation and both results agreed quite well. It was found that the air flow rates were highly dependent on the inside wall temperatures and section ratio of solar chimney for a given section area. The results showed the temperature difference of 0.4℃ at the top of the solar chimney, the pressure difference of 0.2-1Pa and the air velocity of 0.05m/s for the solar chimney section area of 4.93m^2. It is expected that the natural ventilation by the 8m high solar chimney with 4.93m^2 of section area could provide about 5900m^3/h of ventilation on days from the results of CFD simulation.

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東京都心のビル屋上において，アゼスゲ(湿生区)とノシバ(シバ区)の試験区を設け，温度上昇抑制効果及び熱収支特性を評価した。その結果，シバ区，湿生区の屋上面の夏期晴天時の平均温度は平均気温より低く，屋上面の熱流の発生量も少なかった。さらに，湿生区の屋上面の温度はシバ区に比べ0.5～0.7℃ 程度低く推移する傾向が見られた。湿生区は，群落内の温度が外気温よりも低くなり，蒸発散による潜熱と，アゼスゲ地上部による日射の遮蔽によって，冷却が効率的に行なわれていることが明らかになった。群落内の低温は，群落上にも影響を与え，屋上面の温度上昇抑制だけではなく，群落上の冷却という形でヒートアイランド現象を緩和することが示唆された。湿生区は潜熱の発生量が多く，顕熱と植生基盤の蓄熱量の和はマイナスの値をとる期間が多くなったことから，熱収支からも冷却効果を裏付ける結果を得た。

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