The meteorological services in Japan were initiated in 1875 and Japan Meteorological Agency is responsible as the National Meteorological Services. The major services are to issue the weather forecast in short-range, the warning/advisory against the typhoon and heavy rainfall. In order to ensure these services, JMA is continuously improving its systems of observations, national/intemational telecommunications and weather analyzing/forecasting. JMA has been making every effort to meet these social needs in improving the forecast in short-range and climate-related activities.

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Instabilities and vortical structures in the near wake of spheres and circular disks are reviewed, together with those of elliptic disks and rectangular disks which have two length scales. The linear global instability analysis (Natarajan & Acrivos 1993) yields critical Reynolds numbers of regular and Hopf bifurcations of the sphere wake, which are in excellent agreement with direct numerical simulations and experiments. The Strouhal number of shedding of hairpin-like vortices in the sphere wake is significantly dependent on Reynolds number, reflecting changes in vortex structure in the wake such as transition from laminar to turbulent flow. The vortex structure at high Reynolds numbers still remains to be clarified. Two periodic components exist in the wake of elliptic disks and rectangular plates of aspect ratio of 2 and 3, being caused by global instability in the near wake.

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Recently, development and utilization of wind energy have attracted interest both in technical and economical point of view among private sectors as well as local governments. The introduction of wind energy was accelerated in 1999 and the cumulative wind power capacity in Japan reached 100MW at the beginning of 2000. A capacity level of 150MW is very. close. A commercial wind farm of 20MW capacity was constructed in December 1999 and the another 30MW wind farm is under construction. The Government started new research programs on wind energy in order to develop wind turbine generator systems that are suitable for the Japanese external conditions. The decentralization in the electric power industry has started in March 2000.

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A brief summary of events surrounding the alarming collapse of America's Tacoma Narrows Bridge, on November 7th, 1940, is provided, followed by comments from one of the actual observers of the collapse, Professor F. B. Farquharson of the University of Washington. A difference of opinions concerning the actual cause of the collapse has since led to considerable strife between two of the bridge industry's most prominent individuals - Mr. 0. H. Anmann and Mr. D. B. Steinman, This tragic accident served as a seed for the birth of today's bridge aerodynamics. Advancements in bridge aerodynamics facilitated:(1) the reconstruction of the Tacoma Narrows Bridge;(2) the construction of the Mackinac Bridge, which, at completion, boasted of the longest suspension spans in the world; and (3) the recent development of streamlined (aerofoil) box sections.

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The Building Standard Law was revised in June 1998 in Japan. It was the first major revise after it had been established 50 years before. The trigger is said to be an agreement between the President Clinton of USA and a former Prime Minister Hashimoto. They made a promise on reducing the non-tariff barrier. They say that the revise of the Building Standard Law was decided as the result. This is a good example of internationalization of the building code. Since these situations are in actuality, we have to take into consideration of international harmonization when we discuss domestic code problems. However information of international activities does not seem to be widely distributed. In this paper, ISO activities and the relevant APC activities are introduced focussing wind load regulation. The wind load provisions in the revised Building Standard Law Enforcement and the relevant technical regulations are introduced as well as the Housing Performance Indication System in the Housing Quality Assurance Act. The information shearing is expected to have a great help when we proceed into the next step of international harmonization of building code.

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Stratospheric airship, that is ultra long duration high altitude airship, is somewhat different from conventional design airship. Mission altitude is about 20km, because winds are relatively weak around that altitude through the year. Solar cell and regenerative fuel cell equipped airships are able to be geostationary against air stream for long duration without fossil fuel exhaust to atmosphere, that is environment-friendly. Design point of view, no mass change is essential during mission flight, soit is necessary for altitude control to close airship hull against superheat phenomenon. Development of super pressurized hull structure with new high tensile strength material is critical technology for this flight vehicle. Airship design, tracking and control are very sensitive to wind condition, so the cooperation of meteorologists and aerospace engineers is very important for this challenging project.

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