The Middle East and the United Arab Emirates (UAE) in particular is a rainfall deficient region of the world. Few studies have been conducted in this region that relate to cloud processes and atmospheric chemistry and composition. A project was initiated in 2001 to study rainfall process and radiative properties of clouds over the United Arab Emirates. Two intensive aircraft campaigns were undertaken in 2001 during winter (January-March) and summer (June-September)

Emissions to the atmosphere in the United Arab Emirates were thought to be mostly aeolian desert dust that are considered to be inefficient cloud condensation nuclei. Industrial activities in the UAE are a large source of accumulation mode sulphate aerosols. The adjacent Arabian Gulf is also a substantial source of sodium chloride aerosols in the atmosphere. The co-existence of the three main aerosols types in the atmosphere over the UAE provide unique environment for studying the interactions between aerosols and clouds by modifying the cloud condensation nuclei spectrum and explore the interactions with clouds and the effects on radiative and precipitation processes.