"The main goal of this project is to characterize the amount of atmospheric aerosol particles formed, transported and deposited within deep convective clouds over the Amazon. In addition, we will quantify the impact of perturbations to the natural aerosol population on deep convective cloud properties. The European Union has in its 7th research framework program (FP7) recognized the need for increasing our knowledge of the interactions between the climate, biosphere, ecosystems and human activities. Aerosol-cloud interaction has also been identified by the Intergovernmental Panel on Climate Change (IPCC) as a key uncertainty in our current understanding of the climate system. Aerosol composition in the tropical environment is dominated by carbonaceous compounds. The sources of these compounds vary throughout the year, from oxidative processing of biogenic volatile organic gases during the clean, wet season to direct injection of biomass burning aerosols and organic gases in the polluted, dry season. By combining the experienced researcher’s in-depth knowledge of organic aerosol modeling with the aerosol and cloud expertise available in the host environment, we will develop the first cloud-resolving model to explicitly account for in-cloud organic aerosol formation, growth, and removal. The model will be able to simulate in detail the dynamical and microphysical evolution of a deep convective cloud, as well as the two-way interaction between the cloud and the atmospheric aerosol population. Using the new tool, together with upcoming and available in-situ measurements from different aircraft campaigns over the Amazon, we will increase the knowledge regarding the issues pointed out by FP7 and IPCC. We will also improve the description of aerosol-cloud interaction processes in large-scale air pollution and climate models."