Preliminary study of the vertical structure of mountain wind in nagano city, central japan

To examine the mitigation effect of mountain wind on urban heat island (UHI), air temperature and wind profile data were obtained by a tethered balloon, a pilot balloon and a helicopter observation in center of Nagano city, central Japan when mountain wind blew. These observation results suggest that, 1) a strong mountain wind developed and flowed into the center of Nagano on fair night with light wind, 2) the depth of mountain wind was estimated to be from ground level to approximately three hundreds meters, and 3) relative cooler air mass penetrating into above the city center by mountain wind indicates to be able to mitigate the UHI