Assessment of environmental conditions using automatic monitoring systems

Knowledge of the oceanographic processes is based on the availability of reliable time series of parameters characterizing sea water. The paper presents the design and use of systems based on a computer co-ordinating data acquisition and transmission activities from several instruments (multiparametric CTD probes, colorimetric Loop Flow Analyzers for nutrient determination, meteorological sensors, thermal infrared radiometer....). According to the environment (distance from the base station, space and power availability and maintenance facilities) and need for immediate data availability, different technical solutions have been chosen and designed for the communication equipments and the "stand-by" status of the equipment: fully remotely controlled systems for data acquisition and real time transmission under the control of the "base station" self controlled systems, automatically performing data acquisition and storage, for further "off-line" transmission when called from the "base station". The systems implemented use both an UHF link with a packet switching radio modem and a cellular GSM phone with integrated modem. Several versions of the systems have been built, with different sensors and hardware components, and installed in Messina (1996) and Venice (1997) as a part, respectively, of the activities of the CNR Strategical Project for Automatic Monitoring of Marine Pollution in Southern Italy Seas and of the PRISMA 2 programme, aimed at the study and safeguard of the Adriatic Sea; a newer version is under test. A selection of the acquired data is presented, showing the adaptability of the systems to different sites, whose hydrodynamics depends on tide, currents, or meteo parameters, using different tracking parameters (temperature, salinity, nitric azote, fluorescence and chlorophyll "in vivo") to assess the environment status.