Abstract
Non-technical summary
This study examined how glaciers contribute to streamflow and hydropower production in Norway’s Jostedøla River Basin (2000–2014). Model simulations suggest that glacier meltwater significantly supports the largest power plant (38.5%), whereas others rely on rainfall and groundwater flow. In June, snowmelt from areas without glacier cover supports streamflow during Warm and Dry days. However, in August, neither snow nor glacier meltwater can compensate for the rainfall deficit. We found that smaller power plants are more vulnerable to water intake fluctuations. Qualitative analysis reveals the differences between model results and stakeholder perceptions, potentially hindering effective climate adaptation and energy security efforts.
Technical summary
This study utilized a series of models to simulate the surface energy balance for meltwater production, soil water balance, and runoff routing, alongside semi-structured interviews and surveys. It examined glaciers’ contribution to streamflow and hydropower production, and stakeholder perceptions of these contributions in the Jostedøla River Basin, southwestern Norway (2000–2014). Whereas rainfall and baseflow are the most significant contributors at all studied power plants, glacier meltwater accounted for 38.5% of the intake at the largest power plant. In June, snowmelt from non-glacier-covered areas offset low rainfall, but in August, neither snow nor glacier meltwater compensated for deficits despite a high glacier meltwater contribution. Small-pondage plants are more vulnerable than reservoir plants to seasonal and annual fluctuations in intake.
Interviews and surveys with hydropower operators in the Jostedøla basin reveal agreement and disparity between perceptions and modeled results: operators recognize glacier meltwater’s contribution at power plants with significant water storage and assume no contribution at smaller run-of-the-river plants. The company reports overlooked glacier loss, framing climate change as beneficial due to higher precipitation. Reduced meltwater would diminish production, lowering municipal revenues from taxes and electricity sales and threatening funding for social services and local development.
Social media summary
Study reveals glaciers’ role in southwestern Norway’s hydropower production and the challenges of climate adaptation.