Abstract
Atmospheric turbidity coefficients were calculated at five sites (Nemuro, Sapporo, Shionomisaki, Tosa-Shimizu and Ishigaki) in Japan from 1980 through 1995. Theturbidity coefficients ranged 0.03-0.30 at Nemuro, 0.05-0.45 at Sapporo, 0.05-0.45 at Shionomisaki, 0.03-0.40 at Tosa-Shimizu and 0.03-0.40 at Ishigaki. In 1982-1984 and 1991-1993 they had the maximum due to large volcanic eruptions of Mt. E1 Chichon and It.Pinatubo, respectively. Except effect of the volcanic eruption, the turbidity coefficients had tendency of increase from 1955 through 1990 due to increase of human activities. Global increase of the turbidity coefficient of 0.042 may cause the decrease of the global mean surface temperature of 0.3°C.
