Sea level rise effects: Where? When? How? Forsooth?

Despite the overwhelming evidence pointing towards recent eustatic sea level rise, there is still a lack of clarity (and even incredulity in some cases) as to whether, where, when, and how the effects of sea level rise are becoming apparent on the coastal interface. To investigate these questions, we conducted a study on the intertidal environments of far northwest Tasmania using time series aerial photographs, extensive field mapping of geomorphology, vegetation surveys and wind wave modelling. Results from the study provide good evidence that sea level rise has been happening and has resulted in extensive shoreline retreat with an apparent onset of progressive erosion around 1968-1975. There is a high correlation between the wave-power and mapped shoreline erosion which is consistent with sea level rise as the underlying cause and variable wave exposure as the principle control on the resulting patterns of erosion. The erosion of mature trees and shrubs, landward transgression of saline vegetation and the exposure of very old soil deposits further add evidence to the onset and effects of sea level rise. The findings from this research have several implications for understanding the mechanisms of sea level rise and assessing the vulnerability of coastal values in view of their adaptation management.