Error determination in the photogrammetric assessment of shoreline changes

The evaluation of error or uncertainty in shoreline change studies is an issue of prime importance for providing an adequate framework for calculated rates of change and to allow the establishment of threshold values above which the rates would be significant. In this note, a practical, easy-to-use method is presented to estimate error involved in the calculation of shoreline changes on aerial photographs, including the three most used types of shoreline indicators: high water line, dune/cliff toe and cliff top. This approach takes into account the specific characteristics of each shoreline proxy, such as relief in the case of the cliff top or tidal oscillations in the case of the high water line. At the same time it includes the error components that are independent from the proxy, basically related to the technical aspects of the process such as photo scanning and georeferencing. A practical example of application of the method is provided for several types of data inputs, based on shoreline changes around the Bay of Cádiz (SW Spain)

Coastal resources

© Springer International Publishing AG 2018. The extreme importance of coastal zones for countries with highly-populated coastal areas has been discussed in Goncalves and Awange, J Surv Eng, 2007, [2] who highlight the concerns about their future, particularly on the state of their natural resources that provide life support and opportunities for economic development and tourism for these countries (Clarck, JR, Integrated management of coastal zones, 1992, [3] ). However, one of the main environmental problems facing coastal areas the world over is that of coastal erosion, which includes, e.g., beach erosion and other natural and anthropogenic environmental factors that are present along the shoreline