Hydropower in Cold Climates Under Climate Change: A Systematic Review

In cold climate regions, hydropower operations depend on predictable snowmelt and stable ice conditions. However, climate change is disrupting these patterns through earlier snowmelt, shorter ice-influenced period, and rising winter inflows. These shifts challenge existing reservoir rules and complicate efforts to align hydropower production with evolving seasonal energy demand. Despite extensive research, there remains a lack of synthesized data specifically addressing these challenges in cold climate regions. To address this, we conducted a systematic review of 103 peer-reviewed studies and technical reports, complemented by insights from operators, experts, and regulators from regions with snow/glacial-influenced basins. The inclusion criteria focused on studies examining hydropower operations, climate change hydropower adaptation, and cold-climate or Nordic conditions, while the exclusion criteria included studies written in non-English languages, those centered on tropical, arid, or semi-arid hydropower systems, and studies lacking relevance to operational or environmental aspects. The review focused on (i) consequences of climate-driven hydrological and cryosphere changes for hydropower operations, (ii) vulnerability of hydropower intakes, spillways, and dams to changing hydrological and ice conditions, and (iii) adaptation strategies, including flexible rule curves, multi-objective optimization, and ice control methods. The review indicates that climate change is already undermining hydropower resilience in cold-climate regions, altering runoff seasonality, shifting ice regimes, and increasing hydrological variability. Earlier snowmelt, higher winter inflows, and reduced summer runoff commonly lead to seasonal mismatches between water availability, electricity demand, and market conditions.  At the same time, ice-related processes such as frazil ice formation, intake clogging, and ice jams remain major operational risks.  Although some studies suggest potential increases in annual hydropower production, these gains are often offset by increased spill losses, constrained summer generation, and growing conflicts between energy production, flood control, and environmental flow requirements. This work provides a structured basis for enhancing operational resilience by integrating scientific evidence with stakeholder perspectives.