Thermal implications of hydropeaking activity in regulated Arctic rivers

River temperature is an influential variable for biologic activity in arctic rivers. Regulated discharge regimes can have significant impacts on water temperature on both short and long time scales as water discharged through subterranean power stations is often a significantly different temperature than water flowing in the bypass reach. As a result, river temperatures downstream of a hydropower station's discharge point are influenced by the power station's electric production schedule and the relative temperatrures of bypass flows. The discharge strategies for the Norwegian hydropower network are likely to shift in the future, as wind power potential is harnessed in northern Europe. A seasonal shift in hydropower production could, in turn, affect aquatic ecology through thermal alteration. This work aims to investigate the current effects of regulated discharge on river temperature in Norway and to estimate the influences that alterations in discharge patterns would have on river temperature in the future.