Coastline Mapping

Coastline changes can be analysed approximately forty years back in time based on different remote sensing data sets. Recently declassified US spy satellite images provide a unique data source for information about the stability of coastal environments. When combined with modern high resolution satellite images, long time series of coastal development can be analysed. The processing of US spy data is relatively complex, but GRAS has expertise in processing these data sets for coastal monitoring in many parts of the world.

Overview analyses can be done using a combination of US Spy data and Landsat data. This will allow an analysis of coastline changes with 4-5 images in the period 1960-2005 and an accuracy of app. 15 metres.

Higher accuracies can be obtained by combining the spy data with SPOT which is available in the period 1986 to present. In this way accuracies can be within 5 metres. For detailed studies of recent phenomena, very high resolution data can be used to map coastline changes at extremely high accuracies. Using QuickBird data with a spatial resolution of 60 cm, the results are comparable to aerial photography.

Coastline monitoring is an important step in many coastal engineering projects such as harbour construction and for coastal protection. Furthermore, coastline change detection is an important environmental parameter, i.e. in connection with erosion from storm impact or human disturbance.