Changes in river ice cover in the context of climate change and dam impacts: a review

Abstract This article presents a review of previous studies on the impacts of climate change and the operation of dam reservoirs on the characteristics of river ice cover. Based on a review of the existing literature, the spatial and temporal variability of trends in individual river ice cover conditions and their relationship to both climate change and the operation of dam reservoirs is explored. From this analysis, climate change is identified as the main determinant of the river ice cover disturbances observed since the start of the twentieth century. The study found that in the twentieth century, climate change contributed to a decrease in the duration of ice cover on rivers. The shortening of ice cover duration occurs primarily through earlier breakup rather than later formation. The trends in ice cover freeze-up and breakup are less spatially variable across Eurasia than in North America. The analysis indicates that dam reservoirs can exert a significant control on the spatiotemporal distribution of ice cover occurrence on rivers, even on a global scale. The first quantitative estimate of the number of dam reservoirs in river ice cover areas was also presented based on climatological and reservoir location data. The obtained results highlight the need to research river ice cover changes based on remote sensing data; such studies will make it possible to recognize the temporal–spatial distribution of trends in river ice cover parameters and the strength and extent of the influence of dam reservoirs.