APPEARANCE AND DRAINAGE AREAS OF THE COLD AIR STREAM ON THE SLOPE OF Mt. OMATSU, SUGADAIRA, CENTRAL JAPAN

Climatological Features of Sub-Hourly Temperature Variations in Japan

“…It is expected that the surface cold air is easily removed downslope at these sites. A number of observational studies at Sugadaira revealed repeated discharge and accumulation of surface cold air accompanied by wind and temperature variations during nighttime (Nakamura 1978;Kudoh et al 1982;Yoshino 1984;Toritani 1985). Similar variations were observed at other mountainsides (Doran and Horst 1981;Owada et al 1995).…”

“…Yokoyama et al (1981Yokoyama et al ( , 1984 described the wave motions observed in the nocturnal inversion layer having a phase speed similar to that of a shallow-water wave. Many researchers described the intermittency of drainage winds along mountain slopes accompanied by wind and temperature variations (Nakamura 1978;Kudoh et al 1982;Yoshino 1984;Toritani 1985). Ookubo et al (2005) reported large temperature variations on time scales of approximately 1 h around Lake Suwa (Fig.…”

Development of a Nocturnal Temperature Inversion in a Small Basin Associated with Leaf Area Ratio Changes on the Mountain Slopes in Central Japan

“…Croplands and sports grounds occupy in the basin bottom, and the mountain slopes are covered by deciduous trees (mostly Larix kaempferi (Japanese larch), Betula platyphylla (Japanese white birch), and Quercus crispula (Japanese oak)) and evergreen trees (mostly Pinus densiflora (Japanese red pine)). Grasslands used for gelande and pastureland also spread along the mountain slopes where Nakamura (1976Nakamura ( , 1978 observed the characteristics of gravity currents due to radiative cooling. Kudoh et al (1982) and Toritani (1985) revealed the development of an inversion layer with an 80-90 m depth in the basin synchronizing the occurrence of gravity currents in the case of calm nocturnal weather.…”