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Observations of sea ice and the upper ocean from three moorings in the Beaufort Sea quantify atmosphere–ice–ocean momentum transfer, with a particular focus on the inertial-frequency response. Seasonal variations in the strength of mixed layer (ML) inertial oscillations suggest that sea ice damps momentum transfer from the wind to the ocean, such that the oscillation strength is minimal under sea ice cover. In contrast, the net Ekman transport is unimpacted by the presence of sea ice. The mooring measurements are interpreted with a simplified one-dimensional ice–ocean coupled “slab” model. The model results provide insight into the drivers of the inertial seasonality: namely, that a combination of both sea ice internal stress and ocean ML depth contribute to the seasonal variability of inertial surface currents and inertial sea ice drift, while under-ice roughness does not. Furthermore, the importance of internal stress in damping inertial oscillations is different at each mooring, with a minimal influence at the southernmost mooring (within the seasonal ice zone) and more influence at the northernmost mooring. As the Arctic shifts to a more seasonal sea ice regime, changes in sea ice cover and sea ice internal strength may impact inertial-band ice–ocean coupling and allow for an increase in wind forcing to the ocean.

Ocean submesoscale currents, with spatial scales on the order of 0.1–10 km, are horizontally divergent flows, leading to vertical motions that are crucial for modulating the fluxes of mass, momentum, and energy between the ocean and the atmosphere, with important implications for biological and chemical processes. Recently, there has been considerable interest in the role of surface waves in modifying frontal dynamics. However, there is a crucial lack of observations of these processes, which are needed to constrain and guide theoretical and numerical models. To this end, we present novel high-resolution airborne remote sensing and in situ observations of wave–current interaction at a submesoscale front near the island of O’ahu, Hawaii. We find strong modulation of the surface wave field across the frontal boundary, including enhanced wave breaking, that leads to significant spatial inhomogeneities in the wave and wave breaking statistics. The nonbreaking (i.e., Stokes) and breaking induced drifts are shown to be increased at the boundary by approximately 50% and an order of magnitude, respectively. The momentum flux from the wave field to the water column due to wave breaking is enhanced by an order of magnitude at the front. Using an orthogonal coordinate system that is tangent and normal to the front, we show that these sharp modulations occur over a distance of several meters in the direction normal to the front. Finally, we discuss these observations in the context of improved coupled models of air–sea interaction at a submesoscale front.

Some form of regeneration occurs in all lifeforms and extends from single‐cell organisms to humans. The degree to which regenerative ability is distributed across different taxa, however, is harder to ascertain given the potential for phylogenetic constraint or inertia, and adaptive processes to shape this pattern. Here, we examine the phylogenetic history of regeneration in two groups where the trait has been well‐studied: arthropods and reptiles. Because autotomy is often present alongside regeneration in these groups, we performed ancestral state reconstructions for both traits to more precisely assess the timing of their origins and the degree to which these traits coevolve. Using an ancestral trait reconstruction, we find that autotomy and regeneration were present at the base of the arthropod and reptile trees. We also find that when autotomy is lost it does not re‐evolve easily. Lastly, we find that the distribution of regeneration is intimately connected to autotomy with the association being stronger in reptiles than in arthropods. Although these patterns suggest that decoupling autotomy and regeneration at a broad phylogenetic scale may be difficult, the available data provides useful insight into their entanglement. Ultimately, our reconstructions provide the important groundwork to explore how selection may have played a role during the loss of regeneration in specific lineages.