Abstract
This paper discussed the land and sea breeze circulation (LSBC)between Ishikari and Yuhutsu areas in Hokkaido. The diurnal variation of LSBC during boreal summer(July and August) of 1985-2009 was mainly investigated by using various data. LSBC was observed between Ishikari and Sapporo up to 13km from coastal zones of the Japan Sea. Tomakomai to Atsuma area also showed LSBC around16km from coastal zones of the Pacific Ocean. For inland region that area from Chitose to Naganuma, southerly wind was observed all day long. The reason is related to a fact that this inland region has strong southerly wind associated with the meridional temperature gradient between Ishikari and Yuhutsu area. Thermal balance between SST and temperature of land could be important to control the horizontal scale of LSBC. In the La-Nina years, SST over the Japan Sea at the vicinity of Sapporo area was higher than the climatology, and LSBC was enhanced and expanded its spatial scale.
