Abstract (EN):
Several areas of the western coast of Portugal are undergoing severe erosion. Accurate
knowledge of coastal morphology and morphodynamic characteristics as well as their correlation
through time is of great importance, not only to identify coastal erosion hazards, but also to
understand more in-depth the movement of sediments and the action of currents, which are the
main coastal processes responsible for erosion.
The main goal of this work is to develop a tool capable of performing aerial image analysis,
visual and computed, of coastal forms and wave breaking zones The results of this analysis will be
integrated and made available through a GIS database. With this approach, it will be possible to
typify, classify and analyse coastal physiography, and the coastline evolution, in a medium to long
term period, as well as the hydromorphologies and coastal forms resulting from the wave action.
The first step of this work was to store the available data into a GIS database, namely the images
from the 1996 and 2001 surveys. All the surveys that don¿t have coordinate systems were georeferenced
using AutoCAD Map 2002 and ArcInfo 7.2.1. In parallel, a tool made with Matlab 7.0 ¿ namely its
toolbox image processing ¿ is being developed to analyse the stored images. Also, another tool
using Geographical Information Technology (GIT) is being used to perform some more aerial
image analysis.
The preliminary results of this work indicate that this approach is satisfactory. The analysis
system is performing well but some improvements can be introduced to the Matlab tool in order to
make it able of processing imagery analysis disregarding its resolution. So far it is still unable to
process high resolution images which are currently under development.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
10
License type: