At CIAO, research activity is conducted in cooperation with the main ground-based observation networks (EARLINET, ACTRIS, CloudNet, AERONET, NDACC, GRUAN, GALION, BSRN), with the main goal to provide long-term observational data relevant to climate and air quality research, supporting satellite missions (NASA, ESA, JAXA) and in cooperation with the modelling community (ECMWF, AEROCOM etc.). Data quality also matches the protocols developed in the frame of the international networks in which active and passive instruments are operational.

The CIAO infrastructure hosted international satellite validation experiments, it has been involved in several international experiments for the study of aerosols and clouds and their modelling, and it is among the fifteen backbone stations involved in the operations of GRUAN (GCOS Upper-Air Reference Network).