With the synergistic use of ground-based measurements and modelling predictions, the applicability of the Aerosol Index as extracted from OMI/Aura observations is assessed as a potential parameter that can quantitatively describe the aerosol load over the city of Thessaloniki, Greece. Even though it is rightly assumed that the spade of satellite measurements will highly complement and aid the use of ground-based observations, great care is required in the interpretation of their joint findings. Sun photometer and lidar ground-based measurements of aerosol optical depth and space-borne observations of the aerosol index during 2005 were utilised in this work to study the varying aerosol load over Thessaloniki. The city is situated in a unique sea-side location, while being frequently affected by biomass burning and desert dust particles arriving at the location. Local and regional pollution further affects the quality of the local air and the observed tropospheric optical depth. Two categories of discrete atmospheric aerosol loading were examined in detail; with the combined use of dust loading modelling over the Mediterranean area and lidar measurements days with significant Saharan dust loading were identified. Further to this, ATSR-2 World Fire Atlas observations over Europe and Russia were superimposed over back-trajectory calculations of the air-mass arriving over Thessaloniki hence identifying biomass burning events. In addition, results from a three-month observational campaign during the summer of 2005, combining OMI/Aura overpasses with detailed sun photometer, cloud cover and lidar measurements are presented.