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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B7, 2012 
XXII ISPRS Congress, 25 August — 01 September 2012, Melbourne, Australia 
METHODS FOR MULTITEMPORAL ANALYSIS OF SATELLITE DATA 
AIMED AT ENVIRONMENTAL RISK MONITORING 
M.Caprioli ^, A. Scognamiglio 
* POLITECNICO DI BARI, Dipartimento di Vie e Trasporti, 70125 Bari, Italy - m.capriolitopoliba.it 
? POLITECNICO DI BARI, Dipartimento di Vie e Trasporti, 70125 Bari, Italy — a.scognamiglioGpoliba.it 
Commission VII, WG VII/5 
KEY WORDS: DEM/DTM, LIDAR, Satellite, Stereoscopic, Photogrammetry, Remote Sensing 
ABSTRACT: 
In the last years the topic of Environmental monitoring has raised a particular importance, also according to minor short-term 
stability and predictability of climatic events. Facing this situation, often in terms of emergency, involves high and unpredictable 
costs for public Agencies. 
Prevention of damages caused by natural disasters does not regard only weather forecasts, but requires constant attention and 
practice of monitoring and control of human activity on territory. Practically, the problem is not knowing if and when an event will 
affect a determined area, but recognizing the possible damages if this event happened, by adopting the adequate measures to reduce 
them to a minimum, and requiring the necessary tools for a timely intervention. On the other hand, the surveying technologies 
should be the most possible accurate and updatable in order to guarantee high standards, involving the analysis of a great amount of 
data. The management of such data requires the integration and calculation systems with specialized software and fast and reliable 
connection and communication networks. 
To solve such requirements, current satellite technology, with recurrent data acquisition for the timely generation of cartographic 
products updated and coherent to the territorial investigation, offers the possibility to fill the temporal gap between the need of 
urgent information and official reference information. 
Among evolved image processing techniques, Change detection analysis is useful to facilitate individuation of environmental 
temporal variations, contributing to reduce the users intervention by means of the processes automation and improving in a 
progressive way the qualitative and quantitative accuracy of results. 
The research investigate automatic methods on land cover transformations by means of "Change detection" techniques executable on 
satellite data that are heterogeneous for spatial and spectral resolution with homogenization and registration in an unique digital 
information environment. 
In the present work we tested some areas of study particularly interesting for the knowledge of the morphology changes of land 
cover, in particular the area of Fasano in Apulia Region (Italy) and protected area of the Park of Alta Murgia, both of them with 
frequent episodes of land transformation. 
We tested the usability of heterogeneous and freely available images to realize a DEM extraction process to achieve fast and low 
cost system of analysis. 
We used archival stereo-pairs Ikonos and LIDAR survey comparing with Aerial photogrammetric DEM extraction. 
1. INTRODUCTION strategies and accomplishments, allowing modification of 
actions when the expected effects are not achieved. 
In recent years research in the field of geometric correction of 
satellite data has reported remarkable methodological advances, 
implementing registration and ortho-rectifying algorithms 
which are now consolidated methods for the international 
scientific community. 
Generally, such procedures are carried out to correct or to 
eliminate image errors due to the bad functioning of sensors and 
to the atmospheric diffusion effects. Quality of data also 
depends on the intensity of spectral distribution of energy 
received by the sensor, with significant variations in its passage 
through the atmosphere. 
The automation and repeatability of the procedure on 
constantly updated data will permit the development of a 
monitoring system for land cover transformations with 
environmental risk, not only to support preliminarily decisions 
in strategic planning contexts, but also as a tool to verify 
To detect and classify a landslide, it is necessary to view the 
size and contrast of its features and the morphological 
expression of the topography within and around the landslide. 
Determining parameters are the type of movement that has 
occurred, the degree of present activity of the landslide, and the 
depth to which movement has occurred. The most common 
remote sensing tools used for the detection and classification of 
landslides are satellite imagery and aerial photography. 
Monitoring landslide movement involves the comparison of 
landslide conditions over time, including the aerial extent of a 
landslide, its speed of movement, and the change in its surface 
topography (i.e. DEM comparison) . 
The fundamental merits of the high resolution remote sensing 
are the ability to perform surveys at regular intervals in the 
operation, the characteristics of the image and the revisit times. 
These features are very useful in environmental monitoring