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Abstract Tides are an important factor shaping the sea ice system in the Arctic Ocean by altering vertical heat fluxes and advection patterns. Unfortunately, observations are sparse, and the analysis of tides is complicated by the proximity of wind-driven inertial oscillations to the semidiurnal frequencies. Furthermore, computational costs typically prohibit the inclusion of tides in ocean models, leaving a significant gap in our understanding. Motivated by summer observations showing elevated downward surface heat fluxes in the presence of tides, we analyzed simulations carried out with an eddy-permitting coupled ice–ocean model to quantify the impact of tidal effects on Arctic sea ice. In line with previous studies, we find an overall decrease in sea ice volume when tides are included in the simulations, associated with increased vertical mixing and the upward flux of heat from deeper layers of the Arctic Ocean, but this sea ice volume decrease is less pronounced than previously thought. Surprisingly, our simulations suggest that in summer, Arctic sea ice area is larger, by up to 1.5%, when tides are included in the simulations. This effect is partly caused by an increased downward surface heat flux and a consequently lower sea surface temperature, delaying sea ice melting predominantly in the Siberian Seas, where tides are moderately strong and the warm Atlantic Water core is located relatively deep and does not encroach on the wide continental shelf. Here, tidally enhanced downward heat flux from the surface in summer can dominate over the increased upward heat flux from the warm Atlantic Water layer. Significance StatementThis study sheds light on the complex and understudied role of tides in Arctic sea ice dynamics. By utilizing advanced computer models, our research uncovers that, contrary to common expectations, tides contribute to a seasonal increase in sea ice area by up to 1.5% in summer. This effect is attributed to enhanced advection of sea ice into the Siberian Seas and a local increase in downward heat flux reducing sea surface temperatures, thereby delaying sea ice melting in this region. Our findings challenge prevailing notions about the negative impact of tides on sea ice and highlight the importance of incorporating tidal impacts in ocean models to improve predictions of Arctic sea ice changes, key for our understanding of both Arctic and global climate dynamics. 

The Greenland Ice Sheet Ocean Science Network (GRISO) organized an informal meeting during the Fall 2024 American Geophysical Union (AGU) Meeting that brought together an interdisciplinary and international group of researchers, government scientists, funding agencies, and representatives from Greenland. The goals of the meeting were to 1) facilitate interactions across individuals and groups that conduct and support research in and around Greenland (including Greenland Ice Ocean Science Network [GRISO], Future of Greenland ice Sheet Science [FOGSS], funding agencies, and more) and 2) promote discussion of how to best contribute to Greenland's National Research Strategy. We asked attendees to provide constructive feedback to the following questions: 1) Supporting capacity building for Greenland-led research is an important goal. How can we (individuals, organizations, etc.) best participate in capacity building? The more detailed or specific your suggestions or comments are, the more helpful! 2) What do you most want, what would be most helpful, and/or what is missing from a coordinated US domestic and/or international effort in Greenland? Again, the more detailed or specific your suggestions or comments are, the more helpful! 3) Please provide any ideas, questions, interests, or other things for the community to connect about. This is a catch all topic, but detail is helpful here too. The written report provided here details attendees responses to these questions in summary form. There is also a list of the 46 participants, including Greenlanders and US funding agencies.