Coastal storms have increased in recent decades, affecting many species, including the South American sea lion (Otaria byronia). Reports of stranded sea lion pups are becoming common in Chile, presumably due to the increase in the frequency and intensity of coastal storms. to validate this assumption, a 10-year database was built by coupling wave generation and coastal propagation models to correlate pure wave parameters (significant wave height Hs, peak period Tp, normalized wave power Hs 2 Tp) and wave parameters including the tidal level (maximum surface elevation η, modified wave power η 2 Tp) with records of stranded pups in Cobquecura, the largest breeding colony in central chile. the correlation between the number of pups stranded per day and wave parameters in the first half of January and the last half of February is poor, while they are stronger for the second half of January and the first half of February. The higher number of stranded pups coincide with coastal storms with normalized wave power values exceeding a threshold of 100 m 2 /s. Conversely, below this threshold there is wide dispersion between the number of strandings and wave parameters. identifying wave parameter thresholds could be used to predict when newborn pups will be most affected by coastal storms, and thus help institutions to develop remediation techniques for animals at risk. Climate variability and change in the marine environment are emerging issues that have been reported to affect a wide range of species in different ways 1-4. Signs of climate change include changes in air and sea surface temperatures, a rise in the absolute mean sea level, changes in salinity, ocean acidification, and increased frequency and intensity of extreme events, among others 5. All of these signs are causing shifts in the abundance and distribution of several species, loss of habitat and changes in survival rates and breeding success. Some responses have been relatively consistent among species, such as a general advance in the timing of breeding and the migration of several bird species 6,7. However, other responses, like population size and breeding success are less consistent, and vary by species and location 8,9. Most studies on climate change in marine environments have focused on the rise in temperature and changes in the availability of resources 10,11. Other effects, such as the occurrence of coastal storms, have been overlooked, even though extreme events are expected to become more common over time, as they are associated with climate

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The web-based tool ARClim provides an atlas of climate change-related risk assessments spanning over 50 environmental and productive sectors in Chile. This paper illustrates the implementation of ARClim on two coastal sectors, operational downtime in fishing coves and flooding in coastal settlements, aiming to provide a tool to visualize comparative estimates of risk, which may enable decision makers and stakeholders to prioritize adaptation measures. The risk is calculated as a function of the hazard, exposure, and sensitivity. Exposure and sensitivity are characterized using present day information. To assess the hazard, wave climate for a historical period (1985–2004) and a projection (2026–2045) were modeled with six general circulation models (GCMs) for an RCP8.5 scenario. Similarly, sea-level rise was computed from 21 GCMs. Results show that the flooding hazard is mostly dependent on sea-level rise, with waves playing a minor role. However, the flooding risk is highly variable along the coast, due to differences in the exposure, which strongly depends on the population of each settlement. The analysis of increased operational downtime in fishing coves also shows risk, which is dependent of the size of each site. Lastly, limitations of the analysis and opportunities for improvement are discussed.

Charles Darwin and Robert FitzRoy documented coseismic coastal uplift associated with the great 1835 Chile earthquake (M > 8.5) at Isla Santa María. In 2010, another similar earthquake (Mw 8.8) uplifted the island, ending the seismic cycle. The 2‐m uplift in 2010 caused major geomorphic and sedimentologic changes to the island's sandy beaches. Understanding the processes governing these changes requires pre‐ and post‐earthquake measurements to differentiate the effects of abrupt coseismic uplift from seasonal, annual, and decadal‐scale signals. Here, we combine spatial analysis of aerial imagery, field geophysics, wind and wave models to quantify geomorphic changes between 1941 and 2021 along the main beach. During the late interseismic phase (1941–2010), a ridge‐runnel system was formed and then buried by a frontal dune. Because of uplift in 2010, the shoreline prograded ~20 m, the uplifted berm was abandoned, and a new seaward berm was built. In the following decade, the abandoned berm was eroded by widening of the backshore as the shoreline and dune advanced seaward. Over the surveyed eight decades, the shoreline prograded continuously, increasing from <1 m/year to up to 3–5 m/year after the earthquake. We infer that these changes were caused by a sedimentary disequilibrium driven by variations in relative sea level, moving formerly passive sands from eroding cliffs and marine depths into the coastal sedimentary system, thus promoting long and cross‐shore sediment transport and, utterly, accretion. Our results have implications for studying beach evolution along tectonically‐active coasts associated with drastic changes in relative sea level.