Volatile organic compound concentrations within a tropical plant canopy and atmospheric boundary layer: initial flux estimates and contributions to the GoAmazon campaign

Correctly simulating cloud formation processes in the tropics remains a major research challenge. The Amazon experiences the deepest atmospheric convection and largest emission of volatile organic compounds (VOCs) on Earth. The biological, chemical, and physical pathways involved in the flux of VOCs to the atmosphere in the tropics remain poorly understood. The role of atmospheric VOCs in the creation of secondary organic aerosols and cloud condensation nuclei, to the eventual development of convective precipitation, requires a combination of models and measurements that captures the complex dynamics while remaining simple enough to be represented in global models. Here, we describe initial results from the project ‘Bridging land-surface fluxes and aerosol concentrations to triggering convective rainfall' (PI Chamecki) and its contributions to the larger GoAmazon project. Initial findings of the March 2014 intensive campaign near Manaus will be presented. These observations include VOC concentrations within the canopy measured by a profiling system, and within the atmospheric boundary layer measured via tethersonde. Initial VOC flux estimates will be presented and a strong focus will be placed on understanding biotic and abiotic controls over VOC flux, as well as transport processes within and above the tropical forest canopy. Future research including the development of a 1-D transport model and a large eddy simulation will be described to place results in a broader context.-->