Evaluating the U.A.E.’s Orographic Cloud Seeding Techniques: A Comprehensive Analysis of Cloud Seeding Microphysics and Particle Microstructures.

Abstract

Although our knowledge of cloud seeding techniques has increased substantially over the past few decades, there remains a lack of overview of its efficacy and procedures across spatial scales. (1) In this paper, we analyze the 219 cloud seeding events conducted by the U.A.E.’s National Center Of Meteorology. (2)\xa0These events aimed to improve agriculture and mitigate the negative effects of summer drought. We analyze the microstructures of cloud particles and the microphysics of air volume and sediment interaction to identify which of the U.A.E.’s cloud seeding techniques were most efficient. First, we evaluate the conditions conducive to cloud condensation nuclei (CCN) formation through the collision-coalesce model and nucleation. Second, we consider cloud particle sedimentation, collision rates and aerosol concentrations to explain cloud behavior and cloud stability during seeding. Third, we analyze the surface tension of spherical particles and how they affect CCN grouping and collision success. Lastly, we examine current static, hygroscopic, dynamic and nanotechnology cloud seeding techniques implemented globally and identify which techniques are most suitable for the U.A.E. to adopt. We find that given the natural U.A.E. climate and the safety concerns associated with uncertain nature of emerging cloud seeding technology, it is best to use non-chemical hygroscopic methods to maximize condensation and rainfall in a sustainable way.