1990年代前半の気温の変動とその原因

The variation of atmospheric temperature of early 1990s and its cause

氏名: 室谷 宏一
指導教官: 守田 治



 From 1992 to 1993, the decrease of global mean surface temperature took pla ce. Especially, this event was prominent in the midlatitude of northern hem isphere. In Japan, agricultural products was damaged from cool weather in s ummer of 1993.

 It was considered that this unusual weather was caused by the eruption of Mt. Pinatubo on 15 June 1991. This event was already investigated by many researchers using the observationed data from the orbital satellite SAGE I I [e.g. McCormick et al. , 1992 ], or using climate models [e.g. Hansen et al. , 1992]. While, it is well known that the El Nino event in 1991/1992 h ad influenced on the surface temperature in the midlatitude of the northern hemisphere.

 In this thesis, the effect of the eruption of Mt. Pinatubo and the El Nin o event on surface temperature in the midlatitude of the northern hemispher e is researched by the correlational analysis and the causal analysis. The result of the analysis clearly suggests that the eruption of Mt. Pinatubo i nfluenced largely on the surface temperature but the El Nino event did not so much as the former.