Investigating river ice phenology and climatology in the northeast United States and the link with climate oscillations

The goal of this study is to conduct a comprehensive assessment of river ice phenology and climatology in Northeast United States, utilizing a combination of in situ observations and satellite imagery. Spatial and temporal patterns of ice formation, ice breakup, ice concentration, and breakup ice jams were analyzed. Investigation into how river ice phenology varied during the period 1985–2023 was performed using conventional trend analysis methods, alongside an examination of the teleconnections between ice phenology series and global climate oscillations. Complex spatiotemporal evolution of river ice across the Northeast United States was detailed, with notable influences of latitude on ice cover dynamics due to temperature variations from north to south highlighted. Leveraging 12 years of daily satellite observations, the necessity of integrating satellite imagery with in situ observations to develop a comprehensive river ice climatology was emphasized. Trend analysis indicated delays in ice formation by an average of 0.45 days per year and a tendency for earlier breakup by 0.24 days per year. However, these changes were not statistically significant. Trends in hydroclimatic variables, such as air temperature, snow cover, and rainfall, were discussed. Additionally, a considerable increase in mid-winter breakup ice jams frequency was revealed, with a significant change noted post-1992. The findings of this study pave the way for the development of regional river management strategies and adaptation to river ice-induced hazards.