Climatological Research on the Local Wind “Yasuda-Dashi” Arising in Niigata Pref

  • Yuma IMAI, 2013: Climatological Research on the Local Wind “Yasuda-Dashi” Arising in Niigata Pref .

Abstract


In some areas on the Japan Sea coast of Hokuriku and Tohoku region, the local easterly strong winds called “Dashi” arise. The “Dashi” winds are considered to get strong in the place where gorges are opened up to plains. Above all, “Kiyokawa-Dashi” in Yamagata Prefecture and “Arakawa-Dashi” and “Yasuda-Dashi” in Niigata Prefecture are famous. In this paper, climatological features of “Yasuda-Dashi” are taken as a target because of its few prior studies. As a result of analysis, it is revealed that the wind only strengthens around the outlet of the Agano gorge. It also seems to arise frequently in spring and seldom in summer, and to occur not in the afternoon but at midnight and in the morning. These spatial distribution and temporal properties suggest that the wind relates to synoptic pressure gradients and solar radiation. However, there are some obscure points on its structure and generation mechanism yet. Therefore, such issues are expected to solve soon.

Keywords:gap wind, Yasuda-Dashi, Agano gorge, spatial distribution, temporal properties, Niigata Pref.