GOAMAZONPRTTOF

Observations and Modeling of the Green Ocean Amazon: Proton-Transfer-Reaction Time-of-Flight (PTR-TOF)

1 February 2014 - 15 October 2014

Lead Scientist: Scot Martin

Observatory: AMF , MAO

The hydrologic cycle of the Amazon Basin is one of the primary heat engines of the Southern Hemisphere. Any accurate climate model must succeed in a good description of the Basin, both in its natural state and in states perturbed by regional and global human activities. However, tropical deep convection in a natural state is poorly understood and modeled, with insufficient observational data sets for model constraint. Furthermore, future climate scenarios resulting from human activities globally show the possible drying and the eventual possible conversion of rain forest to savanna in response to global climate change. Based on our current state of knowledge, the governing conditions of this catastrophic change are not defined. Human activities locally, including the economic development activities that are growing the population and the industry within the Basin, also have the potential to shift regional climate, most immediately by an increment in aerosol number and mass concentrations, and the shift is across the range of values to which cloud properties are most sensitive. The goal of ARM Climate Research Facility in the Amazon Basin was to understand aerosol and cloud life cycles, particularly the susceptibility to cloud aerosol precipitation interactions, within the Amazon Basin. The ARM Mobile Facility was located downwind of the city of Manaus, Brazil (3 6' 47" S, 60 1' 31" W) near Manacapuru from January to December 2014. The site was situated so that it experiences the extremes of (i) a pristine atmosphere when the Manaus pollution plume meanders and (ii) heavy pollution and the interactions of that pollution with the natural environment when the plume regularly intersects the site. The central Amazon where this site was located is only weakly influenced by biomass burning emissions in the dry season. The city of Manaus uses high-sulfur oil as its primary source of electricity; the city is also an industrial zone of 3 million people and has high emissions of soot. Particle number and mass concentrations are 10 to 100 times greater in the pollution plume compared to the times when pristine conditions prevail. The deployment enabled the study of how aerosol and cloud life cycles, including cloud-aerosol-precipitation interactions, are influenced by pollutant outflow from a tropical megacity.