Michael Harlow
Urban Development Detection within the Upper Thames River Conservation Authority for the Period 1991 - 1999 using Landsat TM and ETM+ data © 2003
The use of remotely sensed satellite image data for the generation of information concerning large areas is relatively inexpensive when compared to other methods. Urban development within the Upper Thames River Conservation Authority (UTRCA) was determined using an image differencing approach for the period 1991 to 1999. Six urban regions within the UTRCA were examined, ranging in population from over 400000 to less than 4000. Band 2 differencing was found to be the most adept technique for determining development, in combination with a three class Minimum Distance supervised classification of the region. Accuracies of the initial remotely sensed classification were improved following orthophoto post classification editing, producing an overall accuracy of 90% with user's and producer's accuracies ranging between 84% - 98%. Results show the UTRCA experienced 17.36km2 of urban development over the study period. Smaller urban regions had the highest percentage rates of development, while slightly lower growth levels were found in two 'middle' sized cities.