Locating shoreline changes in the Porttipahta (Finland) water reservoir by using multitemporal landsat data

Abstract

Both scientific and technical investigations and the planning of water reservoir areas for different purposes all require accurate base information on water areas in the form of preliminary orientation maps. These are in principle most easily obtained by using the Landsat multispectral scanner (MSS) data in CCT form. Computer-aided analysis such data allows us to survey and interpret the water reservoir environment both in time and in space on a scale which is very laborious through in-situ mapping. Repetitive coverages of Landsat MSS digital imagery data over the Porttipahta water reservoir in northern Finland have been processed by using a computer for enhancement of changing shoreline features. Temporal variations in the water reservoir area have been mapped to accentuate the Landsat CCT data-processing method for volumetric estimation of stored water, for preparing topographic shoreline maps of different water levels, and for shore environment change analysis. The multi-year analysis of digital Landsat data gives important information about environmental changes within the water reservoir area in a relatively short processing period. In the case of reservoirs in flat or mosaic-topography areas the mixed pixels may lead to some difficulties.