THE RESEARCH PROGRAMME OF Â ¿UDR GAIA CONSISTS OF CARRYING OUT AND TESTING ON THE GROUND A NETWORK OF INNOVATIVE DEVICES DEDICATED TO COLLECTING DATA ON THE CHARACTERISTICS OF AEROSOLS IN THE ATMOSPHERE THROUGH MEASURES OF DIRECT AND DIFFUSE SOLAR RADIATION. THE DATA WILL BE COLLECTED VERY CAREFULLY (E.G. 5-10 MINUTES) THROUGHOUT THE WHOLE DAY OF THE DAY THANKS TO THE TRACKING SYSTEM INTEGRATED INTO THE INDIVIDUAL DEVICES. THE DATA WILL BE COLLECTED AUTOMATICALLY FROM A CENTRAL DATABASE, WHERE THEY WILL BE DISTINGUISHED ACCORDING TO THE LOCATION OF EACH SENSOR. IN PARTICULAR, TWO TYPES OF SENSORS WILL BE DEVELOPED, ONE FOR THE MEASUREMENT OF THE DIRECT SPECTRAL RADIANCE OF THE SUN. THE DATA WILL THEN BE MADE UP OF COUPLES/SUN SPECTRUM PAIRS/IMAGINDELETED, AS WELL AS BY SEVERAL ENVIRONMENTAL PARAMETERS SUCH AS TEMPERATURE, UMIDENTS, PRESSURE, ETC.