In recent years change monitoring has become an increasingly important issue, particularly for landforms and areas that are potentially hazardous to human life and assets. The coastal zone is currently a sensitive policy area for those involved with its management, as phenomena such as erosion and landslides affect the stability of both the natural and the built environment. Examples of high profile events are the Holbeck Hall landslide at Scarborough in 1993, the loss and subsequent restoration of Miami Beach, Florida, and the many villages lost to the sea on the Holderness coastline in East Yorkshire. As well as the problems of natural erosional processes, the construction of sea defences has often compounded problems, altering the sediment balance further along the coast. With legal and financial implications of failing to predict and react to such geomorphological change, the provision of accurate and efficient monitoring is essential. Long coastlines and dynamic processes make the application of traditional surveying difficult, but recent advances made in the geomatics discipline allow for more effective methodologies to be investigated. A solution is presented, based on two component technologies – the Global Positioning System (GPS) and digital small format aerial photogrammetry – using data fusion to eliminate the disadvantages associated with each technique individually. The solution was based on the use of digital elevation models (DEMs), computer representations of the natural terrain surface. A sparse but highly accurate GPS DEM was used to control surfaces derived from photogrammetric processing to an established datum – necessary for comparing temporal series. Results of this methodology were encouraging, the flexibility, redundancy and automation potential allowing an efficient approach to landform monitoring.
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