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.

Assessment of the impact of dam reservoirs on river ice cover – an example from the Carpathians (central Europe)

“…The method presented in this paper and the results obtained here may be of significant importance in the study of the ice regime of rivers at local, regional, and global scales. This is due to the significant increase in the number of dam reservoirs in ice cover areas since the beginning of the second half of the 20th century (Fukś;2023). It has been estimated that there are more than 8,000 such facilities, most of which are located in areas where ice cover on average lasts a relatively short time, from 15 days to 3 months (Fukś, 2023).…”

“…This is due to the significant increase in the number of dam reservoirs in ice cover areas since the beginning of the second half of the 20th century (Fukś;2023). It has been estimated that there are more than 8,000 such facilities, most of which are located in areas where ice cover on average lasts a relatively short time, from 15 days to 3 months (Fukś, 2023). In Europe, most of the reservoirs in areas where river ice is present are located in the central region and on the Fennoscandian peninsula (Fig.…”

“…9). In areas of ice cover, a particularly large number of reservoirs are also located in central North America and central and eastern Asia (Fukś;2023). Moreover, these are areas where a significant reduction in the duration of river ice cover has been observed over the past 40 years (Yang et al, 2020).…”

“…Most studies focus on assessing the impact of individual reservoirs, neglecting the regional and global aspects of this issue. It has been estimated that there are more than 8,000 dam reservoirs in ice regime areas, most of which are located in central and northern Europe, eastern Asia and the central section of North America (Fukś, 2023). The main difficulty in assessing the impact of dam reservoirs on river ice cover comes in distinguishing whether changes are due to operational or climatic factors.…”