Abstract
This paper investigates influence of base flow discharge on stream temperature formation in a river network for refining a stream temperature network model. A base flow temperature at a spring water spot has been observed for several years in Ibo River Basin in Japan. The data indicate that there is a time delay with a few months in the peak temperatures between the surface flow and base flow, so that the base flow could give higher temperature input into the stream water body in winter and lower input in summer. A newly proposed base flow temperature model with the stream temperature network model shows very high prediction ability for the temperature distribution structures along the river network for all seasons.
