81 
Large projects like Alexandria at the University of 
Berkeley (http://alexandria.sdc.ucsb.edu), aimed at 
creating an extensive digital library including maps, 
photos, texts and multimedia documents, are still under 
way. A fuzzy, as opposed to crisp, geographical selection 
may perhaps better satisfy the needs for some 
environmental applications. 
However, the simple system described in this paper has 
already shown definite advantages. It exploits 
geographical relations that can be automatically 
managed, to provide a structure to non-homogeneous 
data sets, so that they can be conveniently searched and 
retrieved. This greatly eases the exchanging of 
information and allows its archives to grow wider and 
wider to better satisfy the needs of various types of users. 
Its disadvantages are due to the effort that the users still 
have to make to manage the data they have found. Each 
data set is in fact stored in its original format (plain text, 
word processor, worksheet, and database, GIS) and thus 
requires a specific program to be elaborated. However, 
given the number of actors working in the field, this seems 
almost unavoidable: the adoption of a common standard 
would pose such a burden on the data suppliers to 
practically prevent their contribution to the growth of the 
data repository. The only feasible alternative to this 
approach seems the creation of a unique organization 
(even if formed by a federation of agencies) than has the 
power of imposing a certain data description standard. 
The web site is presently a part of a larger web project 
(http://pc-ambiente.como.polimi.it) basically built for 
teaching purposes. It includes a section with 
downloadable map files of the Lombardy region, a direct 
connection with some instruments showing in real-time 
the main meteorological values in Como town, and a 
modelbase containing description and reference for some 
200 environmental models. Finally a number of case 
studies are presented, developed within the framework of 
the GAIA EU Project (http://www.ess.co.at/GAIA). They 
illustrate how to deal with actual environmental problems 
from problem statement, to data collection, model 
implementation and policy consequences. 
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