Technical Note Multi-temporal change of Lake Brullus, Egypt, from 1983 to 1991

Change detection algorithms have been applied to MSS data for monitoring changes inside and outside the Lake Brullus environment. Analysis of the results reveals occurrence of erosion and accretion along both sides of the lake inlet. During the study period (1983 to 1991), the lake area decreased by an average rate of 8·6 km2 per year mainly due to drying for land reclamation. Comparison between standardized and unstandardized principal components showed that the standardized PCs are more capable of identifying occurring changes. A simple technique, such as image differencing and ratioing, comprises a powerful method to emphasize changes, especially when we use thresholding.