三瓶演習林の気象の変遷

Climatic condition has been observed over 40 years at Sambe Forest, Shimane University. According to our observation, average temperature, annual rainfall and average snow depth were 13℃, 2,390 mm and 82 cm, respectively. Maximum temperature was observed July and August. Rainfall concentrated into summer, especially in July. We usually had snow from November to April with maximal in February. The climatic condition at Sambe Forest fluctuated to some extent. During past 40 years, however, we detected no difference in five-year average of the temperature, rainfall and snow depth. As an unusual event, we experienced extraordinary snowfall in 1963. Sambe Forest had more than 100 cm snow even in March with maximal snow depth of 245 cm in February. In sum, the climatic condition was rather stable at Sambe Forest.

　自然環境の制約の中で行わざるをえない農林水産業では，当地の気象条件を把握せずには産業がなりたたない．気象条件はかなり狭い範囲内でも異なり気象台や測候所の観測だけでは不十分である．よりこまかいメッシュでの気象観測が必要である．
　また，酸性降下物や地球環境の温暖化の影響についても日々の気象データの積み重ねなしでは議論も意味をなさない．
　三瓶演習林でもこれまで断続的ではあるが業務として気象観測を行ってきた（山下ほか１９９８）．ここで昭和２８年以来蓄積された三瓶演習林での気象データを解析し，三瓶演習林近辺の気象条件を特徴づけ，その変遷を明らかにする