We also know that, whether by human or natural agency, the features of the land change over time. So the map drawn yesterday is no longer useful today, and has to be replaced to ensure the faithful representation of reality.
Computer science can make a valuable contribution to the problem of updating maps. Today, the majority of maps used by technical experts are in digital format, i.e. one that can be displayed on a computer.
When something changes on the ground, only the changes which are strictly necessary must be made to the image. If we remember that digital mapping is mainly produced by processing aerial photographs or by satellite technology, we can immediately see that frequent automatic regeneration is possible. Digital images can be viewed, and if necessary processed, using special graphics programs.
There are also software tools known as GIS (Geographical Information Systems) that, together with the images, can also "process" information regarding the objects present on the images themselves, based on their geographical coordinates. The whole can be made available to the public by direct consultation on the Internet.
This is what the Provincia of Ferrara's Geologists' Association has done with a project supported by public bodies such as the Emilia Romagna Region, the Arpa provincial section, and the Province and Municipality of Ferrara, as well as with the invaluable contribution of the Cassa di Risparmio di Ferrara and its Foundation, and the participation of the local branch of Confidustria.
In this case all the geological and environmental features of the Ferrara provincial region are given: altitudes, soils, geology, geomorphology, rock formations, stratigraphy (or the study of the changes in layers of soil), and the chemical and physical characteristics of the water table.
All this is available, based on the technical cartography of the region, and the Geologists' Association web site www.assogeologi.it, thanks to the installation of a special web server capable of "publishing" maps and data.
Access to and use of the data published thus become simple operations which can be carried out by everyone from anywhere, to the great benefit of the community as a whole: technical experts in the sector have access to a useful and effective tool for their work while ordinary citizens can find out more about the surroundings in which they live.