| Summary: | P(論文) The author, as a meteorological research member of the Wintering Party of the Eleventh Japanese Antarctic Research Expedition in 1969-1971, carried out micrometeorological observations at Syowa Station in Antarctica during the period from February 1970 to February 1971. The results have been reported in the following papers: MAKI (1971); MAKI (1972a, b, c, d); and MAKI (1974a, b). The observations on the structure of the atmospheric turbulence near the ground were made with the sonic anemometer-thermometer for the first time as the main theme of the meteorological research project. This investigation was carried out for the first year in the four year project of ""Explanation of Formation and Structure of Antarctic Anticyclone"". An atmospheric turbulence in stable stratification was measured on the 21 m-high tower built on the sloping terrain of Syowa Station during the period from February to December, 1970. Its characteristics are analyzed in relation to the stability (Richardson number, Ri) in the atmospheric surface layer. The vertical mean wind speed at the height of 20 m is observed to be about one- third of the longitudinal mean wind speed at the same height (U_<20>) above the slope with the inclination of about 10 degrees. The standard deviations of the longitudinal, lateral and vertical wind speed fluctuations decrease exponentially with the increase of Ri. The ratios of the standard deviations of the longitudinal, lateral and vertical wind speed fluctuations to the friction velocity are independent of Ri. The energy dissipation rate increases roughly in proportion to the 0.5 power of Ri. The scale of the atmospheric turbulence seems to be a solid body of a long and narrow cubic vortex having the dimensions of length : breadth : height=6.3:1.9:1. The charac- teristic scale of the atmospheric turbulence which is the largest turbulon (INOUE et al., 1955) is independent of the stability (Ri). Furthermore, the scale of the smallest turbulon increases exponentially with the value of Ri. The ...
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