Introduction
Palma is a web application, with various levels of permissions, designed to facilitate access to data managed by the oasi (Osservatorio Ambientale della Svizzera Italiana) project and which may be used in carrying out the tasks of the services. The data are managed both from SPAAS (Sezione protezione dell’aria, dell’acqua e del suolo) and third party. The content of data are in continuous evolution.
The oasi project
The idea of an environmental observatory is born from the observation of a risk of environmental degradation, caused by the increase of road traffic or by the construction of new traffic facilities, which has accentuated even more the need to track over time and space the evolution of environmental loads, especially the atmospheric and noise pollution along the roadways.
With this in mind, a request was forwarded at the cantonal level in 1999 (Ferrari, 136.99 of 06.21.1999) asking for the setting up of an environmental observatory.
While at the federal level the MFM-U project was developed which aims to monitor the environmental effects of traffic along the A2/A13.
Thanks to these impulses, and especially with the active involvement of Canton Ticino in the MFM-U project, the OASI concept was born, which was developed in synergy by the Dipartimento del territorio and the University of Applied Sciences and Arts of Southern Switzerland (SUPSI).
The OASI creation has become effective on 3 June, 2002 with the Grand Council’s approval of the State Council’s Message and the related legislative decree.
Information system
OASI is also a tool that introduces modern and flexible data management, which is necessary because the mass of data, both existing and new, is enormous.
The OASI information system is an integrated and transparent access system for the user.
It is capable of reprocessing the data to quickly provide an overview of the situation.
The acquired spatial and temporal data are stored into a database, designed so that it can handle data from different domains such as air, noise, traffic, weather, etc.
Different modules act on the database for data quality control , for data analysis and, in the long term, for prognosis.
The data can be accessed directly through the public OASI website or through the Palma application (which this document aims to describe how it works) of direct access that allows more functionality: a sort of environmental e-banking oriented towards sector operators.
Data acquisition
Concepts for permanent investigations have been developed for each sector with the aim of ensuring continuity, accuracy and reliability. Some stations set up automatic survey systems and data acquisition from several measurement stations or other external sources occurs one or more times a day.
The system uses various methods for acquiring data, but in most cases stations continuously send their data to a file transfer protocol (ftp) server. Automated downloading and importing of data into the database is done through a dedicated application.
Negli altri casi il citato applicativo di acquisizione contatta la stazione di misura per scaricare i dati oppure, nei sistemi sprovvisti di una linea di comunicazione, è un operatore che si fa onere di scaricare i dati sul posto ad intervalli regolari.
Point measurements (single samples, control measurements) are insered into the database through special interfaces included in the Palma application.
Quality control
For proper analysis and reliable information, data quality control assumes a key role.
Given the huge amount of data, it is impossible to leave the control work entirely in the hands of different operators, which is why the OASI information system was developped with automated data quality control system.
The first part consists of a sequence of automatic procedures (AQC0, AQC1, AQC2) that are gradually more complex and refined. Then the operator performs validation and, possibly, the correction of the data using the validation module included in the Palma application developed specifically for this task (HQC).
Automated procedures have a dual function: they flag unusual data, allowing any instrument problems to be discovered very quickly, and in addition, they help the operator in the difficult task of distinguishing “corrupt” data that are physically plausible.
Fig. 1 Quality control flowchart