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大学生を対象として簡易に風向と風速を測定できる教材を用いて，約20 mの比高を持つ砂丘の上部から下部にかけて立地する新潟大学五十嵐キャンパス内で気象観測実習を行った．その結果，実習日の気象はどの観測地点においてもほぼ一様であり，砂丘の地形を反映したものではなかった．その一方で，局所的な建物や地面の状態の違いを観測することができた．今回の気象観測自体は実技的な面では特に大きな問題なく行うことができたが，科学的な背景についての深い理解にまでは繋がらなかった．今回の実践をより改良，または単純化することで将来の義務教育の学校現場に活用することができるだろう．

富士吉田森林気象試験地の気候特性を明らかにするため、2000 年から2008 年までの9 年間、気象タワーで観測されたデータを使用して解析を行った。年平均全天日射量、気温、水蒸気圧および風速はそれぞれ、14 . 1 MJm- 2 d- 1、9 . 5 ℃、1 . 07kPa および2 . 1 ms- 1 であった。平均年間降水量は1955 mm であった。主風向は南南西であった。ハイサーグラフは山中のアメダスデータと似通っていた。夏の全天日射量は近隣の気象測候所よりも小さく、標高が高いために雲や霧がかかりやすいことが原因と示唆された。気候区分やNPP 推定モデルから、この試験地は植物の成長には十分な放射量および降水量があることが示された。

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金沢大学環日本海域環境研究センター生物多様性研究部門

富山県の局地風である井波風に関しては，小川（2001）で挙げている。この井波風に関して，砺波平野南部にある不吹堂（ふかんどう）の分布や，成立過程を詳細に述べた，大浦（2000）がある。富山県の平野部各地に見られるスギなどの高木で家屋の周りに囲む屋敷林に関しての簡単なレビューは前号の田畑･田上（2007）や，田畑（2007a）に示したとおりである。本稿では富山県内の，富山･砺波･南砺高宮で 5～9m・s^の風速のときの，他の各地点の風向分布（回数）と，屋敷林の設営方向とを対比する。そして，田畑･山川（2007）や，田畑（2007a）でとらえられなかった，風速区分と地形との関連を解析する。

The Japan Meteorological Agency (JMA) operates a suite of numerical weather prediction models; the Meso-Scale Model (MSM), the Regional Spectral Model (RSM), and the Global Spectral Model (GSM) with horizontal grid spacing of 5 km, 20 km and 60 km respectively. In addition, a high-resolution Local Forecast Mode (LFM) with grid spacing of 2 km has been developed so as to prevent disaster and maintain safe civil aviation at JMA. With this model, numerical experiments of a wind shear in Haneda Airport on February 26, 2006 associated with a Cold Front Aloft (CFA) and dry trough were carried out on the supercomputer of CeNSS. The LFM successfully reproduced the observed time series variation of the wind at Haneda Airport, although the MSM failed to predict the ending time of the southerly wind. The reason is that the dry trough interacted with CFA did not propagate correctly in the MSM. The analysis using the frontogenetical function reveals that the frontolysis led by the one vertical circulation near the nose of CFA took place and resulted to the prevention of intensification of the front. On the other hand, the LFM could simulate the several vertical circulations so that the frontogenesis and the frontolysis appeared at different circulations. These results suggest the frontogenesis (frontolysis) is occurring more appropriately at finer resolution., 資料番号: AA0063154029, レポート番号: JAXA-SP-06-010

From the point of view of preparation of the living environment without the air pollutants, it is necessary to examine the relationship between the wind direction and the land form factor. The purpose of this study was to examine the influence of the landform factor on the wind direction in Sagamihara, Ebina, Zama and Atsugi cities, Kanagawa Prefecture. We used the hourly values of the wind direction in the four cities. The overall trend of the variation of the wind direction in all stations was that from April to September, the wind blew from the north and south, and from October to March, only the north wind blew. We observed characteristic wind roses at all stations. As for the results of cluster analysis, we created a dendrogram which combined the clusters of Sagamihara and Hashimoto and then Sagamidai, Zama, Ebina, and Atsugi. It appears that the wind flows in urban ventilation lanes in these regions. Therefore, in changes of landform the wind direction should be fully examined based on the regional and seasonal character.

It is well known that some topography causes a wind increase and unexpected gust factors. To examine the characteristics of the gust factors by every wind direction throughout Kyushu area, the authors have organized a database of strong wind data classified into non-typhoon and typhoon. The authors have confirmed the different tendencies of gust factors according to the wind direction at several terrains using the database. The database shows that the gust factors of winds by a typhoon are generally higher than by non-typhoon even when the wind speed is high. And the authors have found that the gust factor at Imajuku, the western part of Fukuoka City, is much higher in southern wind direction. Such a database on the gust factors is useful to estimate a peak gust in strong winds.

It is the trend of each municipality to store air pollutant measurements in the database, but adequate collaboration between other databases and systems has not been done. Sagamihara City achieved remarkable development under an urban planning project. However, the abovementioned information about the environment is merely stored in the database due to the large amount of data. We conducted an examination on the purpose of creating a prediction model that can be utilized for antipollution actions. In the examination, meteorological factors such as wind direction, velocity and temperature were used as the factors contributing to the diffusion of the nitrogen dioxide that was emitted into the air. Among all the substances observed and measured at continuous observation stations for environmental pollution throughout Sagamihara City, the data on the nitrogen dioxide that is supposedly emitted from stationary and mobile sources is used for the examination, leading the following conclusions: 1. The nitrogen dioxide density level was high when the wind direction was northwest, north-northwest and east at the city hall, and northwest, west-northwest and south-southeast at Hashimoto. The nitrogen density was high from October to March on a monthly basis and from 19:00 to 24:00 on an hourly basis. 2. In terms of the relationship between the wind velocity and the nitrogen dioxide density, when the wind velocity was high, the nitrogen dioxide density was low, and when the wind velocity was low, the nitrogen dioxide level was high both at the city hall and Hashimoto. 3. In the multiple regression analysis in which the nitrogen dioxide was chosen as a criterion variable and the wind direction, velocity and temperature as explanatory variables, statistical significance was found at the level of 1% for wind velocity, temperature and wind direction at the city hall, and 1% for wind velocity and temperature at Hashimoto. The regression coefficient obtained is necessary for the prediction of nitrogen dioxide density that is a criterion variable. 4. As a result, the following two prediction models for the nitrogen dioxide density were created: The prediction model for the nitrogen dioxide density at the city hall The prediction model for the nitrogen dioxide density at Hashimoto

Snow drifting processes and wind speed profiles by a collector and a blower snow fences were investigated in a cold wind-tunnel. The purpose is to know the effect of wind direction on drift control by snow fences. Snowdrifts were compared among the following three cases about the both type fences. One is a case which the snow fence is perpendicular to the wind direction. The others are it has tilts by 30° and 45°. When the collector snow fence had tilts, amounts of snowdrift by the fence were much less than that in the case of perpendicular to the wind direction. This mainly caused by that the half width of the fence had no effect on decrease of wind speed. On the other hand, the effect of the blower snow fence did not decrease when it had tilts to the wind direction. It is necessary to be investigated where the blown snow deposit in the case that the blower snow fence has tilts.

飛行データの解析精度の向上には、飛行経路に沿った大気の状態量を知ることが重要である。極超音速飛行実験(HYFLEX)で用いた米国NOAA極軌道衛星の観測に基づく大気状態の推定法について述べる。本推定法の精度は、気象ロケット観測結果との比較により評価した。その結果、温度と圧力はU.S. Standard大気モデルを用いるより精度が相当改善され、特に高高度では誤差が数分の1に減少することが確認された。しかし、風の推定の精度は十分ではなく、これは圧力推定の誤差によるものと考えられる。, In flight data analyses, information on the state of the atmosphere (temperature, pressure, and wind) along flight trajectory is necessary for the improvement of accuracy. Estimation of the state of the atmosphere based on NOAA polar orbit satellite remote sensing-data, which was used in HYFLEX (Hypersonic Flight Experiment) flight data analyses, are described. The accuracy of the present estimation is evaluated by comparing, with meteorological rocket observations. It is concluded that temperature and pressure can be estimated by the present method much better than by depending on the U.S. Standard Atmosphere model, and that the error can be much reduced at higher altitudes. However, the accuracy of the estimation of speed and direction of wind were not satisfactory, and are considered to be due to error in pressure estimation., 資料番号: AA0000675000, レポート番号: NAL TM-700

キールチューブ付5孔ヨーメータによって、速度ベクトルを求める場合の基本式を提案した。本基本式は従来の方法に比べて、校正係数が少なく、繰返し法によって解く場合の初期値の与え方を改善して、計算ステップ数を少なくし、圧力計測から風向、風速を求めるまでの計算処理時間を短縮した。本方法による風向、風速の測定精度は従来の方法と同程度であることが実験的に示された。, An attempt was made to improve the data reduction process of a 5-hole yaw-meter with a Kiel tube. A new system of equations to replace the old one is proposed, which is used to derive the magnitude and directions of the local flow velocity vectors. This system is simpler compared with the old one because fewer terms are used. As a result, the time to solve the system of equations by an iteration method is reduced. Also, the way of giving the initial values to start the iteration is improved. The measurement accuracy of the velocity and velocity angles by the present method is the same as by the old method., 資料番号: AA0004162000, レポート番号: NAL TM-678

将来の通信・放送および地球観測などに利用する成層圏プラットフォーム(SPF)飛行船の研究開発が、1998年より文部科学省と総務省の共同プロジェクトとして進められている。2004年度までに、膜材料・構造技術の実証を主目的とした成層圏滞空飛行試験と浮力・熱制御、飛行制御技術を含む運用技術の実証を主目的とした定点滞空飛行試験が小型の無人飛行船により成功している。本稿では、これら飛行試験で行った飛行船の地上ハンドリング技術の評価・解析を通して、将来計画されている大型の技術実証機に関する地上ハンドリング技術の課題などを検討する。, Japanese stratospheric platform (SPF) R & D activities for communications, telecommunications and observations of the global environment in the future started as a joint project in 1998 between the Ministry of Education, Culture, Sports, Science and Technology (MEXT) and the Ministry of Internal Affairs and Communications (MIC). In 2003, a ground-to-stratosphere flight test was carried out and successfully demonstrated membrane material and structure technologies using a small unmanned airship. In 2004, low altitude stationary flight tests were carried out and successfully demonstrated buoyancy control, thermal management, and flight control technologies using another small airship. This paper provides some explanations on the ground handling of small airships and considers ground handling technologies for a large technology demonstrator airship in the future., ISSNの誤記: 1349-1113, Incorrect ISSN: 1349-1113, 資料番号: AA0049795000, レポート番号: JAXA-RM-05-010