The impact of changes in global wave and storm surge climate on the world's beaches

In recent years, a range of studies have highlighted consistent changes in global wave and storm surge behaviour. Climate projections indicate such changes are likely to continue out to at least 2100. In research studies focusing on both observed and projected changes in global ocean wave and storm surge conditions, a recurring assumption is that these changes may be of importance for the long-term management of coastal areas. Despite the extensive research exploring how anthropogenic climate change affects global wind and wave patterns, a conclusive link to resulting impacts on sandy coastlines globally is still uncertain. In this study we address this research gap at both global and regional scales. The global study offers an initial analysis of the potential relationship between historical trend in wave and storm surge parameters globally and sandy shoreline change rates since the 1980s, using the available global datasets. Based on this study, clear changes in wave and storm surge behaviour have occurred at a global scale over the last three decades. However, the study results do not show a definitive connection between the trends in wave and storm surge conditions and the recession/progradation of sandy coastlines. Our conclusion suggests that, at global scale, the long-term variations in oceanographic factors might still be too small to significantly affect the recession/progradation of shorelines. It is possible that primary factors, such as ambient imbalances in coastal sediment budgets are masking any potential connections. Additionally, there is the possibility that the long-term variations are too small compared to the uncertainties associated. The regional study refines the scope of the global analysis by focusing on a detailed analysis of Australia's south-east coast over a 26-year time frame, from 1988 to 2013. Notably, this region is characterized by some of the most pronounced long-term changes in ocean wave conditions anywhere on Earth, which are a