Will climate change lead to militarily severe civil conflicts? In recent years climate change and civil conflict scholars have extended their discussions to whether or not climate change increases civil war onset and a general consensus has been reached. However, it is still not clear if climate change (such as temperature and rainfall fluctuations) also leads to bloodier results if civil conflicts have begun. Using 130 civil conflicts between the period 1960~2006, and temperature deviation as the proxy variable of climate change, this paper examines if climate change affects civil conflict severity. Empirical findings confirm that when the difference between the average temperature of the year civil conflicts start and that of the past 50 years increases, civil conflicts become bloodier. Possible reasons are economic and political concerns triggered by resource scarcity because of climate change. This forces both the government and belligerent groups to fight harder in order to maintain or change the current situations, respectively. The final section of this paper offers policy implications and directions for future research.