1. After 25 years of apparently successful eutrophication management, a recordbreaking mixed bloom of Ceratium furcoides and Aphanizomenon flos-aquae developed unexpectedly in 2019 in the large, polymictic Lake Balaton. The peak concentration of chlorophyll exceeded 300 mg/m 3 , 1.5 times higher than the

Waves influence the shape and size of ice floes through ice break-up (Langhorne et al., 1998) and govern the state of initial sea-ice congelation (frazil vs. nilas) and influence its evolution (i.e., pancake ice; Shen & Ackley, 1991). Waves also impart momentum to the ice as they are attenuated (Longuet-Higgins, 1977;Longuet-Higgins & Stewart, 1962), pushing the ice in the direction of wave propagation and affect ice drift (Feltham, 2005;McPhee, 1980;Williams et al., 2017). Stopa et al. (2018) show wave action to be the dominant control of sea-ice translation drift along the outer edge of the Southern Ocean sea-ice area, the Antarctic Marginal Ice Zone (MIZ). There are also numerous indirect effects of waves on ice, such as modified air-sea heat fluxes and enhanced lateral melt associated with break-up of sea ice (Steele, 1992).Sea ice also governs the wave evolution. Sea ice-induced wave attenuation may be broadly classed into two categories: scattering and dissipation. The former is described by a partial reflection of waves at the boundaries of ice floes, broadening the distribution of wave direction. Scattering by multiple ice edges directly contributes to the exponential decay of the forward-going wave energy. The latter category, dissipation, describes processes which result in loss of energy from the waves. This includes, but is not limited to, internal friction due to ice viscosity, ice

Climate models do not explicitly account for the smaller scale processes of ocean surface waves. However, many large-scale phenomena are essentially coupled with the waves. In particular, waves enhance mixing in the upper ocean and thereby accelerate the ocean response to atmospheric changes. Here, we introduced a representation of wave-induced turbulent mixing into the one-way coupled ACCESS-OM2-025 ocean model to study its effect on ocean heat content throughout the 21st century under the RCP4.5 scenario. We made two projections on ocean heat uptake for the end of the century: one which accounts for wave-induced mixing (the ‘modified’ projection) and the other which does not (the ‘standard’ projection). Both projections showed upper ocean heat content to increase by more than 2.2 × 1022 J. This projected ocean heat uptake was reduced by about 3% in the modified projection. Whilst the inclusion of wave-induced mixing reduces projected ocean heat uptake globally, some areas are expected to warm considerably faster, particularly the North Atlantic sub-tropics, the Tasman Sea, the Sea of Japan, and parts of the South Atlantic.