Although aerial photographs still constitute an important source of information for the coastal geomorphologist, data acquisition is severely limited in cloud-shrouded coastal environments. Sequential radar mapping of remote coastlines, however, will provide a practical and rapid method of updating maps and monitoring coastal processes. Contrasts in signal return from the land-water boundary produce a striking interface on radar imagery which is advantageous for the delineation and mapping of coastal features. Along the Pacific and Caribbean coasts of eastern Panama and northwestern Colombia, marked discrepancies exist between available maps and the actual configuration as revealed by radar.
In addition to the revision of coastal maps, radar imagery also provides the geomorphologist with most of the information interpretable from aerial photographs. Mud flats, beach ridges, natural levees, backswamp basins, beach features, and zones of breaking surf are examples of the observable features. Mangrove swamps, which abound on tropical shores throughout the world, provide a readily recognizable vegetation type which can be unmistakably interpreted from the imagery. Although offshore sediment transport cannot be directly interpreted, inferred trends can be obtained through sequential radar coverage. The Atrato River Delta of northwestern Colombia is cited as an example.
Radar imagery interpretation has indicated marked landform differences between the Pacific and Caribbean coasts of eastern Panama and northwestern Colombia. The partially submerged mountainous terrain of the southeastern coast is contrasted with the mangrove swamps, beaches, and barrier reefs of east-central Panama.