Detailed knowledge of wave climate change is essential for understanding coastal geomorphological processes, ecosystem resilience, the design of offshore and coastal engineering structures and aquaculture systems. In Lake Michigan, the in-situ wave observations suitable for long-term analysis are limited to two offshore MetOcean buoys. Since this distribution is inadequate to fully represent spatial patterns of wave climate across the lake, a series of high-resolution SWAN model simulations were performed for the analysis of long-term wave climate change for the entirety of Lake Michigan from 1979 to 2020. Model results were validated against observations from two offshore buoys and 16 coastal buoys. Linear regression analysis of significant wave height (Hs) (mean, 90th percentile, and 99th percentile) across the entire lake using this 42-year simulation suggests that there is no simple linear trend of long-term changes of Hs for the majority (>90%) of the lake. To address the inadequacy of linear trend analysis used in previous studies, a 10-year trailing moving mean was applied to the Hs statistics to remove seasonal and annual variability, focusing on identifying long-term wave climate change. Model results reveal the regime shifts of Hs that correspond to long-term lake water level changes. Specifically, downward trends of Hs were found in the decade of 1990–2000; low Hs during 2000–2010 coincident with low lake levels; and upward trends of Hs were found during 2010–2020 along with rising water levels. The coherent pattern between the wave climate and the water level was hypothesized to result from changing storm frequency and intensity crossing the lake basin, which influences both waves (instantly through increased wind stress on the surface) and water levels (following, with a lag through precipitation and runoff). Hence, recent water level increases and wave growth were likely associated with increased storminess observed in the Great Lakes. With regional warming, the decrease in ice cover in Lake Michigan (particularly in the northernmost region of the lake) favored the wave growth in the winter due to increased surface wind stress, wind fetch, and wave transmission. Model simulations suggest that the basin-wide Hs can increase significantly during the winter season with projected regional warming and associated decreases in winter ice cover. The recent increases in wave height and water level, along with warming climate and ice reduction, may yield increasing coastal damages such as accelerating coastal erosion.

Climate change is one of the biggest challenges facing development and continuation of sustainable aquaculture in temperate regions. We primarily consider the ecological and physical resilience of aquaculture in the Gulf of Maine (GoM), where a thriving industry includes marine algae, extensive and intensive shellfish aquaculture, and a well-established Atlantic salmon industry, as well as the infrastructure required to support these economically important ventures. The historical record of sea surface temperature in the GoM, estimated from gridded, interpolated in situ measurements, shows considerable interannual and decade-scale variability superimposed on an overall warming trend. Climate model projections of sea surface temperature indicate that the surface waters in the GoM could warm 0.5-3.5°C beyond recent values by the year 2100. This suggests that, while variability will continue, anomalous warmth of marine heatwaves that have been observed in the past decade could become the norm in the GoM ca. 2050, but with the most significant impacts to existing aquaculture along the southernmost region of the coast. We consider adaptations leading to aquacultural resilience despite the effects of warming, larger numbers of harmful nonindigenous species (including pathogens and parasites), acidification, sea-level rise, and more frequent storms and storm surges. Some new species will be needed, but immediate attention to adapt existing species (e.g. preserve/define wild biodiversity, breed for temperature tolerance and incorporate greater husbandry) and aquaculture infrastructure can be successful. We predict that these measures and continued collaboration between industry, stakeholders, government and researchers will lead to sustaining a vibrant working waterfront in the GoM.

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Submerged aquatic vegetation (SAV) provides primary products for the food web, as well as shelter and nursery for many juvenile species. SAV can also attenuate waves, stabilize the seabed, and improve water quality. These environmental services are influenced by the dynamic motion of SAV. In this paper, a consistent‐mass cable model was developed to investigate flow interaction with a flexible vegetation blade. Compared with previous vegetation models, the cable model showed improvements in simulating blade motions in waves with and without currents, especially for “second‐normal‐mode‐like” blade motion. Wave asymmetry would cause blade motion to be asymmetric. However, asymmetric blade motion may also occur in symmetric waves. Results indicate that the asymmetric blade motion in symmetric waves is induced by two major mechanisms: (i) the spatial asymmetry of the encountered wave orbital velocities (wave motion relative to blade) due to blade displacements and (ii) the asymmetric action on the blade by vertical wave orbital velocities. Consequently, the blade motion is asymmetric even underneath symmetric waves unless (i) blade length ( l) is much smaller than the wavelength ( lfalse/L≪1), (ii) blade length is much smaller than the water depth ( lfalse/h≪1) in finite water depth waves, or (iii) water depth is much smaller than the wavelength ( hfalse/L≪1). Peak asymmetric blade motion occurs as lfalse/L increases to a critical value. The peak asymmetry increases with wave height and blade length but decreases with increasing blade flexural rigidity. Blade motion characteristics play an important role in wave‐vegetation interaction, wave‐driven currents, wave‐attenuation capacity, breakage of vegetation and ecosystem services.